Nov. 22, rgo1.]

THE NEW SU.BWAY IN NEW YORK CITY.

By CuAI{LES PRELINJ, C.E., New York. (Continued from page 676. )

THE first part of the fif th section of the subway begios at 41st -street and Park-avenue and ends at 47th-street and Broadway. The contractors are t.he Degnon McLean Contracting Company of New York.

This section of the subway starts with two t unnels, forming a continuation of the East and West tunnels built by Mr. Ira A. Shaler, and which were de­scrioed in Section 4. There is, however, this dif­ference; that while the \Vest tunnel continues on a straight line or tangent, the East tunnel curves

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leaving the station will proceed slowly along the short circular curves and run at full speed on the transition ones.

The subsoil along 42nd-street from Park-avenue to Sixth-avenue consists of an upper stratum of rubbish followed by a. layer of hardpan, resting on the soft rocky bed which forms the cap of the solid rock met below. The first two layers have an average depth of 10ft., so that the roof of the subway had to be excavated through loose soil, and the floor through solid rock. From Sixth-avenue to Broad­way the soil is loose, consisting chiefly of gravel and hardpan ; while from 44th-street to 47th-street, along Broadway, the solid rock comes up close again to the surface. The , roof of the subway from Madison-avenue to ]'ifth-ayenue is nearly 22ft.

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SECTION SHOWING LONG I TUDINAL HEADING, SECOND TRACK

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round so as to effect its junction with the corre­f ponding one at a point nearly 100 ft. north of 41st-street., at which point the four-track standard section of the subway is resumed. In turning round from Park-avenue to 42nd-street, the four­track road makes t he sharpest curve to be found on the entire line. Compound curves are uced, be­ginning with transition, and followed by circular curves. Calling A the tracks of the north-bound local trains, B those of the expre~ses, C the tracks of the south-bound express train~, and D tho.se of the south-bound locals, the lengths of the transit~on curves are as follows :

Ft. ForA . .. ... ... .. . 360

B • • • ... ... .. . 440 c ... ... ... .. . 200 D ... ... .. . ... 275

The dimensions of the circular curves on an angle of nearly 90 deg. are :

Track. Ra.dioe. Length. Ft. Ft..

A 300 293 B 250 174 c 230 163 D 180 147

The north-west end of the circular curves is fol­lowed by tangents until 42nd-street Station is reached. This is one of the most important of the whole subway, being located just opposite the Grand Central Station. The object of placing transition curves at the south end of the circular curves is to allow north-bound trains to run at full speed until they begin to slow down on entering the station by reason of the resistance due to the circular curves, while the south-bound trains on

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from the surface; while at Broadway it is only 3 ft. Various methods of excavating have been used

on this section of the subway, some of which had not been employed at all on any other section. They were devised by Mr. H. C. Sa.nford, M. Am. Soc. C.E., engineer for the contractors, and Mr. W. 0. Briggs, assistant engineer.

The tunnels that continue those which were de-

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scribed in Section 4 are being built by the open­trench method. Where the East tunnel passes under the tracks of the surface cars, it is driven by the usual tunnelling method of a wide heading. The construction of these t unnels has gone on as usual, no difficulties having been encountered. They require, however, very accurate engineering work in locating the lines of the side walls, and also the tracks which are laid along the transition curves. Very accurate work is also required in preparing the cantering, on account of the rise and the span of the arches Yarying continuously, so that no centre can be used a second time.

A considerable section of the circular curves lies under private property at the corner of 42nd-street and Park-avenue. The property was officiaiJy con-

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THROUGH LOOSE 60/l AND THE FLOOR THROUGH ROCK

damned, and the houses torn down, after which the subway was begun by the open-trench method. The line follows 42nd-street, close to the buildings, on the south side, and immediately under the side­walks, while on the north aide it scarcely reaches the curbstone. The object of this unsymmetrical arrangement with respect to the axis of the street is t o get curves of longer radius at the Broadway turning, to prevent the obstruction of traffic, which is greater on the north than on the south side of t he street, and, finally, to take up less private pro­perty under the sidewalks.

Although the contractors are authorised to open two trenches, one on each side, they are trying to carry on the work with only one, so as not to inter­fere too much with traffic. For this purpose they are using different methods in different places, according to the nature of the soil, the depth of the subway, and the traffic of the surface road.

In places where the solid rock comes up near the roof of the subway the work is being carried on in the following manner : Along the south side of the street, and near the sidewalk, a trench 20 ft. wide is carried down so as to reach the plane of the foundations. The sides of the opening are strutted in the usual way, with sheeting planks held in position by horizontal beams placed lengthwise, and kept up by other horizontal beams laid across the trench. Then a portion of the steel bent of the

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st·~?-dard section of the Rubway is erected, after whiCh a. small heading is excavated, and iron !-beams 30 ft. long and 24 in. high are inserted, abuttin<Y with one end on a wooden beam placed across th; .:>teel bents, the other end being supported by short hor.izontal beams kept in place by wooden blocks wluch rest on the rock, as shown in Fi<Y. 49. The I -beams are placed 5 ft. apart from-=> centre to centre, the rvof of the heading being formed of short heavy planks laid across the beams, and parallel to the axis of the street. When the roof of the heading has thus been secured, and the road-bed itself strongly supported, the underlying rock is blasted in order to admit of another panel of the steel bents of the standard section, which is im­mediately erected. The work is afterwards continued by driving another similar heading across the axis of the street and at right angle~ to the trench, after which the iron 1-beams are inserted as described above. The flanges of these beams are surmounted with caps which support the poling-boards and shore the roof of the excavation, as shown in Fig. 50. .After this, the space below the floor of the heading is removed, the corresponding part of the foundation laid, and another panel of the steel bents set up. Continuing in this way, the heading is gradually pushed forward and the rock removed to make way for the last panels of the steel bents. The diagram Fig. 51 shows the sequence of the excavation, the parts bearing the same numerals being driven simultaneously. As soon as the last heading is driven and all the steel bents set up, the wall which encloses the structure on the north side is built and waterproofed, after which the concrete arches of the side walls and roof are proceeded with. On the roof of the structure, small pillars of masonry are next erected for the purpose of supporting the road­bed while the iron beams are being removed and earth rammed in to fill up the void. With this method of working progress has been very rapid.

But where the rock is soft, or where there is con­siderable distance between the top of the solid rock and the roof of the excavation, it is rather dangerous to have the sub5oil so extensively honey­combed. In such cases the following modification has been adopted : A long trench is excavated under the sidewalk at the south side of the street, and carried down to the level of the foundation of the subway, being strutted in the usual manner. Headings 17 ft. wide are driven every 35 ft. apart across the axis of the street, so as to enclose the roof of the subway. They are strongly timbered, as shown in Fig. 52. On top of the solid rock, two wall-plates are placed longitudinally, which carry the inclined struts that support the cap-piece. These timber ribs, made up of 8-in. by 8 .in. beams, are placed 4 ft. apart, and support the poling boards. The boards are planks 3 in. thick ; they support the roof of the heading, and con­sequently also the road-bed of the street. When the roof of the heading has been strongly secured, the rock between the wall -plates is removed. The foundations are laid as soon as sufficient space is cleared, three steel bents of the four­track standard section of the subway are set up, and t he concrete arches of the side wall and roof are erected. Small pillars of masonry are built on the roof thus constructed, in order to support the road-bed, the space all around them being filled in with well-rammed earth.

The bench which was left between the headings is next excavated and strutted ; the struts support­ing the cap-piece of the headings abut directly on the roof already built, instead of resting on the wall-plates, as usual. vVhen the strutting is com­plete, the bench is entirely removed, other steel bents are set up, and the part of the subway thus constructed is made continuous with the part previously built. Fig. 53 shows the sequence of the excavation of the headings.

From Sixth-avenue to Broadway, where only loose soil is encountered, and the roof of the sub­way lies close to the surface, a method of working has been adopted which is very similar to the slice method used in the construction· of the Boston Subway. A long trench is opened on the south side of the street, and the ground divided up into alternate slices of 7 ft. 4 in. and 12 ft. 8 in. Work begins with the larger strips in the order indicated in Fiu. 54. The parts marked l are first removed, and two slices of the subway built. When the surface road is well supported by the roof of ~he new structure, section 2 is attacked. Another shce

E N G I N E E R I N G. [Nov. 22, 1901.

of the subway is t.hen built, and the road-bed thereby supported, after which the intercepting narrow sections marked 3 in Fig. 54 are removed and other portions of the subway constructed and connected with those already completed, so as to form one continuous structure.

be erected on the vacant ground fronting Broad­way, 43rct-street, and Seventh-avenue.

( To be continuccl.}

THE INSTITUTION OF MECHANICAL ENGINEERS. Work is curied on on the longer sections-viz.,

those 12 ft. 8 in. long- in the following manner: At night, the surface of the street is torn down and a wooden platform set in its place. This plat­form is flush with the street and serves for the gener~l traf:fic. The planks of which it is composed are 4 1n. th1ck ; they are placed longitudinally with the axis of the street and are supported by two or more cross-beams abutting against the concrete superstructure of the car-tracks and curbstones. These beams also serve to support the pipes and conduits met with in the course of excavating. Work is carried on from the side trench, and under­neath the wooden platform. Near the ends ef this small section of the subway two trenches are opened, and an 8-in. by 8-in. beam laid across, to serve as the cap-piece of the wooden bent that sup­ports the car tracks. The beam is temporarily strutted with timbers resting on the unexcavated ground ; but when the soil ha<3 been removed and the plane of the foundations of the subway reached, the temporary timbers are replaced by the various members of the bent. As indicated in Fig. 55, t he bent will be formed of a cap-piece and two braced racking posts resting on a mud sill. One of tbese bents is set up at each end of each car track.

When all the earth between the bents has been removed, a part of the subway is constructed; and as soon as the roof is built, the platform is removed from the surface of the street, the space filled in with earth, and small pillars of brick masonry erected for the support of the repaved street and the surface tracks.

The sections, which are 7 ft. 4 in. long, are con­structed in a simpler way. At night, the street is torn up, and a wooden platform fixed flush with the surface. The ends of the platform planks res~ on the roof of the parts of the subway already constructed, and all the work i-; done from underneath. No strutting is needed for the surface tracks, as the undermined lengths are so short.

Whatever the method employed in excavating, the earth is always removed from the side trench. This necessitates hoisting and conveying machines all along the line. These consist of cableways of the Carson Lidgerwood type, already described in Section 3, or a modification of this type built by the master mechanics of the company.

The rock is excavated by blasting, the holes being bored by Ingersoll drills. The explosive used con­tains only 40 per cent. of dynamite. At first only four holes were fired at a time, but the number has gone on increasing, so that ten of them are now fired at once.

Compressed air is used as the motive power for drillin~, hoisting, and riveting. The plant located at 42nd-street, near the East River, is run jointly by Mr. Ira A. Shaler and the Degnon McLean Contracting Company. The compressed air passes from the generating plant through a 10-in. wrought­iron pipe up to 42nd-street and Park-avenue. Here a. 6-in. branch is taken to supply power to Section 4, while the main, reduced to 7 in., goes all along Section 5.A, decreasing continuously in diameter until it is only 4 in. at the end of the section.

This section of the subway has two stations, both of which are on 42nd-street. One is located near Pt\rk-avenue, just opposite the south-west corner of the Grand Central Station, to be used both for express and local trains, while the other station, situated at the Broad way corner of 42nd­street, will be for locals only. The station for the express trains is builv somewhat differently from the one described in Section 3. On account of the small space available, there will be only two island platforms for the local and express trains, the usual side platforms being suppressed. An underground passage over t he tracks will afford communication between the two platforms, and will subsequently be extended into the Grand Cen­tral Station for the accommodation of passengers who wish to avoid the crowded street. The station at 42nd-street and Broad way, being for local trains only, will have two side platform~. This station will h~ve an underground passage communicating with the St. Cloud Hotel, and with a new hotel to

ON Friday evening last, the 15th inst., an ordinary general meeting of the Institution of Mechanical Engineers was held, the President, Mr. W. H. Maw, occupying the chair. The paper set down for reading and discussion was a contribution by Professor W. E. D~lby, of Lon­don, on

THE BALAKCING OF LOCOl\10TIVES.

The President stated that the author would not read the paper as printed, but would give its substance in a lecture. This course was more desirable, as it would enable Professor Dalby to make his meaning clear by means of models and lantern slides, which would illustrate the dyna­mical principles involved in the system of deter­mining the balancing factors which he presented to the meeting.

We commence to print the p~per in full in our present issue, and as the lecture was practically the s -~me in substance as the text, we will only refer to the lucid manner in which Professor Dalby treated a difficult subject before proceeding to the discussion.

The President, before calling on members to speak, said that although Professor Dalby had, in commencing his remarks, stated that the subject with which he was about to deal was an old one, yet he (the President) felt sure tlie meeting would agree that the admirable way in which the matter had been put forward would throw new light on it to many engineers. He hoped that locomotive engi­neers would come forward freely and take part in the discussion, so that practical results might be the outcome of the investigations. It was t.o be regretted that owing to an unfortunate coincidence several of the locomotive engineers of our big rail­way companies were unable to be present that evening. For instance, Mr. T. Hurry Riches, who had attended the council meeting that afternoon, had been summoned back to Cardiff; whilst Mr. Aspinall and Mr. Ivatt, both of whom had intended to be present, were also prevented from doing so by important engagements. He trusted, however, that those locomotive engi­neer members who were unavoidably absent would communicate their views in writing t0 the Secre­tary, so that they might be incorporated in the volume of the Proceedings. Turning to the paper, there was one point which Professor D~lby had not mentioned. That was the effect on the wear of coupling-rods, &c., produced by the distri­bution between two or more pairs of wheels of that proportion of the balance weights introduced to counteract the effect of the reciprocating parts. Professor Dalby had shown how this proportion of the weight might, if concentrated on one pair of wheels, produce slipping. Now, if such slipping did occur, it would follow that the turning effort exerted by the connecting rods, instead of being partially absorbed by the adhesion of that pair of wheels, would be transmitted through the coupling­rods to the other pair or pairs of wheels, causing extra wear on the crankpins, coupling-rod brasses, &c. Mr. T. Hurry Riches had made some experi­ments in this direction, and found that great advan­hge, in regard to wear and tear of the coupling­rod, followed the proper distribution between two or more pairs of wheels of that portion of the balance weights required to counteract the action of the reciprocating parts. Mr. Maw remembered that, forty years ago, his old chief, the late Mr. Robert Sinclair, had adopted the practice referred to.

With regard to the proportion of the weight of the reciprocating parts which it was desirable to balance, little change of opinion appeared to have taken place for many years past. As some present would remember, the practice of balancing the re­ciprocating parts was introduced over half a century ago, and it was dealt with fully in the late Mr. D. K. Clark's treatise on "Locomotive Engines," published, he believed, in 1851. As a consequence of the general attention then drawn to it, many loco­motives constructed during the following ten years or so had the whole weight of the reciprocating parts balanced, with the result that a very uneqal wear of tyres wa13 produced, this inequality of wear being

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Nov. 22, 1901.]

accentuated by the tyres thca being of iron. Very early in the 'sixties, when he was head draughtsman in the locomotive department of the Great Eastern R ail .. vay, he had been instructed by Ml·. Sinclair Lo look into this matter, and to collate the data bearing upon it, with the result that he was led to recommend that in the case of single engines fi ve-eightbs only of the reciprocating weights shonld be balanced. The deduction was agreed to by Mr. Sinclair, and it was adopted as their standard practice for uncoupled engines. For coupled en­gines the amount balanced was slightly greater, and the weights needed were- as he had already stated- divided between the coupled wheels. He remembered, also, discussing this matter in 1862 with the late Mr. Beyer, who told him that his firm had arrived at a similar conclusion, and that they were limit ing the proportion of the reciprocating parts which they bahnced to two­thirds. The present modern practice referred to in the paper was thus of long standing. I t had to be borne in mind that in the early days to which he had referred the recipro­cating parts were, owing to the moderate sizes of cylinders and low steam pressures, very much less -and less even in proportion to the weight on the wheels-than in the engines of to-day, and there was thus less danger of slipping being pro­duced by the b~lancing of such parts than was the case with the weights to be dealt with at the present t ime. On the other hand, the tyres being of iron, the effect of unequal wear produced by the hammer-blow was much more marked. There was one other point on which he would be glad if some information could be elicited during the dis­cussion, and that was the effect of counterbalancing the reciprocating parts on the wear of the main bearings. Mr. T. Hurry Riches had made some interesting observations on this point, which he hoped he would contribute to the discussion in due course, but possibly other locomotive engineers now present might have some facts of the kind to bring forward.

Mr. McDonnell , who rose in response to the invi­tation of the President, said that it was difficult to enter into the details of a paper more or less com­plicated on the sput· of the moment. He could, however, see enough of the author's train of reasoning to show him that the paper was most interesting. For his own part, he had, in balancing locomotives, followed the mathematical investiga­tions of M. Le Chatelier. So far as he could re­member, he balanced about two- thirds of the weights ; but it was some time since he had had such work to do ; he was sure, however, that he never balanced the whole amount. He had also dis­cussed this matter with Mr. Beyer, who agreed with the system of Le Chatelier. He had at one time as his assistant Mr. Park, who did not believe in balancing ; so they tried an unbalanced engine. The results, however, were so unsatisfactory that the engine had to be balanced. The results that followed from hammer-blow were very curious at times. In an Australian engine, which was a heavy one, whilst the rails were light, the rails were broken at distances at which the hammer-blow would strike, say at each length of 18 ft. or 20 ft., corresponding to the circumference of the wheel. It bad always seemed to him a question whether the hammer-blow was sufficiently powerful to break rails, but doubt­less in this case the rails were weak, and the extra stress due to t he blow caused the rail to give way at these particular points.

Mr. C. H. Wingfield referred to that part of the paper in which the author had shown by calculation that two-thirds is about the greatest proportion of the reciprocating mass which should be balanced in a single engine. The engine might not slip, how­ever, because the other wheel may provide safficient adhesion at the instant. The paper also stated that the turning effort on the crank axle must be compared with the couple resisting slipping, this latter couple depending upon the sum of the rail pressures. It seemed to the speaker, therefore, that one cheek of the crank might take the whole of the twisting moment- namely, that cheek which was nearest to the wheel which did not slip. Might it not be that this would account for some of the '' mysterious " breakages of cranks, of which a good deal was heard from time to time.

Mr. Druitt Halpin said that the Yarrow-Schlick and Tweedy system of balancing had been tried on four-cylinder locomotives in Germany. He pointed out, in regard to slipping, that it seemed like a beautiful provision of Nature that where adhesion

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of wheels was most needed- namely, at starting­that it was most marked ; whilst at high speed, when the hammer action was most strongly pro­nounced, the weight of the train kept it going. In regard to rails breaking at distances proportional to the circumference of the wheels, he pointed out that rails were held between two supports as by a rigid anvil 3 ft. apart and tested by a falling weight, whilst the hammer action was of the nature of a gradual blow.

Professor R. Smith said that the balancing of locomotives was a complicated subject, especially when the driving was by more tha.n one axle. The paper referred to the distribution of the mass of a coupling-rod working on three cranks, which might be suspended on the platforms of three weighing machines. He had made a large number of calcu­lations in connection with the balancing of locomo­tives, and he would ask how it was possible to determine how the weight of the coupling-rod was distributed between the three cranks. He con­sidered the diagram giving the driving effort and the couple resisting slipping for a complete revolution with a Lancashire and Yorkshire four-coupled bogie express engine the most interesting in the paper. It was alarming to notice the closeness with which the curve giving the torque on the driving axle approached that showing the couple to resist slipping; but he thought some mistake had been made in the calculation by the author, and he did not think the curves should come so close together. The difficulty of knowing how much effort was exerted by the coupling-rod made the matter very complicated, and one could never be sure of the calculations. If one wheel was worn more than another, it would not travel the same distance for an equal number of revolutions unless it were shoved forward. The cou{>ling-rod might therefore be either in tension O\" compres­sion. For these reasons the share the coupling­rod did depended upon the wear of wheels. He had made many calculations, but had found that uncertainty of this side of the question batHed accuracy. In old locomotives the centre lines of the cylinders were often oblique, and the hammer-blow depends to a large extent on this. The question of steam pressure also enters into the problem when the cylinders are not horizontal. It might be said these were internal forces and did not act on the rail; but it must be remembered that the two parts of the locomotive were connected by springs. The question, however, would not apply to large modern engines with horizontal cylinders.

Mr. A. D. Jones, of Horwich, said that the re­marks of Professor Smith respecting the author's diagram illustrating the driving effort and the couple resisting slipping were worthy of attention. He had ridden many thousands of miles on the engines of the type referred to by the diagram, however, and had never found them slip. He had intended to ask if there was an error in the calcula­tions, but no doubt the author would reply to Pro­fessor Smith. As a matter of fact, these engines (the four-coupled bogie express of the Lancashire and Yorkshire rail way) rode very well, although the 10-w heel passenger engines of the Atlantic type were better. In regard to slipping, there was diffi· culty in running in fog, especially in towns where t here were chemical works, when the rails were rendered greasy by the material deposited on them by the fog ; therefore every point bearing on the causes of slipping deserved careful attention.

The President asked if the speaker had noticed any irregularity in the wear of tyres; to which Mr. J ones replied he could not say he had, but the paper would lead him to look into this matter ; and he was sure other locomotive engineers would find a good deal in it that would lead them to think.

Mr. Masterton, of the South-Eastern R~ilway, was the next speaker, and in answer to a question by the President as to whether it was the practice of his company to put on the driving wheels all the balance weights required to counteract the action of the reciprocating parts, he said that they distri­buted the weights. He pointed out that the author had not considered back-slipping.

Mr. Russell, of the Great Eastern Railway, said that they balanced two-thirds of the reciprocating weights, and in the six-coupled engines distributed the balance on the three pairs of wheels. They found great wear on the tyres opposite the balance weights; but when the balance weights were taken out, they did not have further trouble in this respect. The coupling-rods then acted as balance weights. The engines without special balance

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weights did better than with. 'Fhese engines. had small wheels. With the larger wheeled eng tn e!=l , balanced in t he manner Professor Dalby had ex­plained, they experienced satisfactory res~lts . .

Professor Dalby, in replying to .the dtscussw~, referred to the remarks of t he President, and sa1d that a point might be mentioned wit~ regard t? the almost universal practice of balancmg by weights placed in t.he spokes of th~ wheels. Th~ un­b~lanced forces in the centre hnes of the cylmders aris ing from crank webs, reciprocatin~ parts, &c., were applied to the crank axle at the JOUrnals, and had to be transmitted from there, along the axle to the balance weights in the wheels, t_hus putt~ng a bending moment on the axle, whtch at h1gh speeds was as great as the bending moment due to the steam pressures. This ad~ition~l straining action on the axle could be got rtd of tf the cr~nk webs themselves were extended to form balance weights in the way sometimes seen in marine practice. He was interested t o hear what Mr. McDonnell had said about the breaking of rails by hammer-blow. He had a recollection of reading this in ENGINEERING, but could not find the refer­ence, so had not mentioned it. He was n ot aware that locomotive engines had been balanced in the way Mr. Halpin had mentioned. Professor Smith had referred to the influence of the coupling-rod on the three outside crankpins, and had stated that the Theorem of Three Moments was required to fi nd the respective pressures on the pins ; he would point, however, to the fact that no rod coupling three wheels was ever made without a joint at the centre, either just near the crankpin or on the pin itself ; so that the method given in the paper was quite correct. With regard to the remarks of the same speaker and Mr. J ones, he thought that both had overlooked the statement in the paper that the diagram comparing the driving couple with the couple resisting slipping referred to the driving wheels only. It illustrated that the engine would just be able to do the work it was at the instant doing, without using the coupling- rod, but, as stated in the paper, "if t his had been a single en· gine, a little more steam, and curve No. 1 would cut curve No. 2, slipping being the inevitable result. " The figure in fact showed how exactly the Lan­cashire and Yorkshire engineers have adjusted their design to the work they wanted the engine to do. The diagram therefore was only put forward tc illustrate what would probably take place if there were no coupling-rod. He was glad to hear the remarks of Mr. Russell, as they were a corrobora· tion of his views by one who was engaged in de· signing locomotives. He might say, in extension of Mr. Russell's remarks, that a s ix-coupled engine without balance weights between the spokes is in. correctly described as an entirely unbalanced engine. The coupling-rod is, in fact, a balance weight, providing, of course, that the outside cranks are at 180 deg. with the inside cranks, which is the usual practice. In many cases it might happen that such an engine would be very little out of balance.

The President, in bringing the discus8ion to a close, said that the Secretary would be glad to receive in writing the remarks of any memberd who had been unable to speak, but who desired to add to the discussion.

THE NEXT MEETING. The next general meeting of the Institution will

be held on Friday, December 20, when a paper on '' The Microscopical Examination of the Alloys of Copper and Tin," by Mr. William Campbell, B.Sc., of London, will be read and discussed.

ENGINEERING VALUATIONS. (Oontinuea from page 491.)

HonsEs ; PRELIMINARY ExPENSEs; GooDWILL. THE valuation of horses is almost as much out4 side the duties and ability of an engineer as the valuation of plant and tools is beyond the capacity of the a.udito.r. There are many elements of great uncertainty In the problem : the market price of horses fluctuates to a greater extent and much more rapidly, than that of machinery;' the animals themselves are not only liable to accident-a lia· bility which machine-tools also share with them­but they are also subject to diseases which may prov~ difficult of cure, and, even after cure leave ble~ushes and marks which seriously interfe;e with their sale. Most men flatter themselves that they understand horseflesh, but few rea1ly do unless they have been trained to deal in it, or ba've been

702

educated as veterinary surgeons. The sale of a hor.se frequently depends even more on the pro­fuslO?- or. m~agreness of the season's crops than on the Intrinsic value of the animal. The horse dealer, or veterinary surgeon, is therefore an almost indispensible ally in t ransactions of this character, and his opinion should be obtained when­ever it is deemed desirable t.o review and revise the book value of the horses. A record of the livestock ~ay, however, be usefully kept in the form already g1 ven fo.r lo~se plant an~ tools, the estimated length of working h_fe, an~ estimated ~ale price thereafter (bC?th of which will be extremely problematical), bemg fixed_ by the dealer. at the time of purchase. The exp~r1ence of . earners, tramway companies, a:nd omnibus propnetors shows that the working !ife of a horse IS only from three to six years. This Is much less than the useful period of employment on a farm, the difference arising chiefly from the nature of the ground on which they are employed, and the greater strains thrown upon town horses by paved roads, sudden stoppages, and increased speed of working. Paved roads are destructive to a horse's feet; and trotting over them, or even over ~acadamised roads, with heavy loads to drag, is di~astrous to the leg and other muscles of the animal. All these factors, and also the attention paid to feeding? s~oeing, stabling, and working, tend to comphcat1ons which render the values recorded in the books extremely unreliable, and useful ch iefly for purposes of comparison. After the lapse of a few years, if careful records have been kept, it may be possible to fix an average rate of depreciation which will keep the horses at near the price which could be obtained for them on a favourable sale ; but until the experience of some years has been obtained- not generally, but in the particular factory affected- it will be safe to reduce the value by 25 per cent. per annum. Fortunately, horses do not usually constitute a very heavy pro­portion of the assets, and the tendency to replace them by mechanical appliances is an increasing one, and productive of economy in most engineering and shipbuilding yards.

Preliminary expenses are decidedly not a valu­able asset. They have to be incurred in order to form the company, but they never add to its earn­ing power, nor assist its capacity for work. They are merely a contribution to legal and financing exactions, and a tax on legitimate shareholders. There cannot be any question of valuing them, in the way that land, buildings, and machinery are valued ; the fluctuations which affect real estate and labour-saving appliances do not touch preliminary expenses; the money has been spent, and cannot be recovered, either from the lawyers and State officials who have received it, or from any future purchaser, and there being no ultimate hope of recovery, there cannot be any increase in value. The amount must be written off, and it is good finance to write it off as quickly as possible after profits commence, even if the earlier dividends have to suffer by doing so. This, however, is a question for the consideration of directors, accountants, and auditors, rather than of engineers. It chiefly con­cerns the latter to rem em her that formation expenses have no actual value, and are incapable of acquir­ing any ; when they appear in the balance-sheets as assets it is merely as a book-keeping entry ; an interim statement of how the money raised has been spent, but with an implied understanding that it will disappear when profits commence.

Good will is worthy of a little more consideration than has been given to it by Mr. Dicksee, whose dicta under the several heads of "Goodwill " and ''Patents " appear slightly ambiguous, if not con­t radictory. It may arise in much the same manner as other permanent assets acquire their value ; either by a payment to t he prior proprietor from whom the works are purchased, or by a synthetic process, in which from the various developments of the business, from its completed engineering equip­ment, from its perfected workshop management, and from its careful commercial arrangements, an increased value is given to it as a whole, apart from the separate value of ita several sections. It is an almost inscrutable quantity ; it cannot be valued solely by an engineer unless he is also a financial expert., because it largely depends on commercial methods, and continuance of commercial success; it cannot be valued by an auditor or accountant alone, because of the factors of workshop manage­ment, of exclusive rights, of special t raining of workmen, and special facilities for production, which are essential for the promotion of such corn-

E N G I N E E R I N G. [Nov. 22, 1901.

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ANGLE-BAR BEVELLING MACHINE.

CONSTRUCTED BY J\1ESSRS. DAVIS AND PRIMRO E, ENGINEER , LEITH.

(For Dest;?-iption, see Page 706.)

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mercial success. In t ne former case, that of pur­chase, it must undoubtedly appear as an asset in the first balance-sheet, whether it be written down as depreciated or not ; in the latter it need not necessarily appear in the balance-sheet, but it must be present to the engineer's consideration whenever he is giving thought to the possible or probable sale of his business.

So far as patents, which are the property of the firm either by purchase or original invention , are concerned, it is undoubtedly right that they should be written off within the limits of their respective lives. They confer a monopoly for a limited period only, and on the expiration of that period their value, as patents, has disappeared. It is better that they should be stated in the balance-sheet as a separate item from good will, so that they may be gradually depleted as the exclusive rights tend towards expiration. But it is possible that as the value of the patents, as legal patents, decrease, the value of the good will of the works may increase, and the same process may occur "where a patent has not been purchased, but r emains the property of the original patentee," being worked by the fi rm under a licence. It is not a matter of legal righb or exclusive privilege; the dog· in-the-manger policy is wholly untenable, but the acquired skill of the workpeople, the adaptation of machinery to the end desired, t he technical ability obtained by the

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managers, tnay assure to the firm a virtual com­mand of the market more certain and lasting th;, n the merely legal right could give.

We may therefore assume that in some instances, if not in all, goodwill has a value, and that if it be acquired by purchase it may be represented in the balance-sheet without "the amount being absolutely meaningless." The meaning is that a certain sum has been paid to acquire the reputation which attaches, d ghtly or not, to the trade marks, factory, name of the firm, and established con­nection of the business purchased ; the sum paid may be in excess of the benefits gained, but the amount paid for the machinery in place may also be more than the advantage afforded by having it ready for immediate work ; but the payment has been made, and it is as intelligible a balance-sheet entry to place the goodwill among the assets as it is to include the machinery there. Whether on a re-sale the second purchaser would or would not be influenced by this amount is hardly the question. If he were wise, he would re-value the asset himself, and might even estimate it at a higher value than appeared in the balance-sheet, but using the latter figure for the purpose of abating any higher price demanded by the vendor. No establishment would stand in exactly the same position at the second sale as at the first, even if only a short interval of time elapsed between the

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profits an absolute test of increase or decrease. The profits of most trades, calculated on turnover, have shown a marked decline during recent year~; but t he decline has been general, not merely through one trade, but throughout the chief t rades of the country. Arising as it does from causes independent of management of particular works, and being fostered by the large amount of surplus c~pital waiting investment, it induces capita­lists to deal very liberally with any firm offer­ing to sell a business which in the past has been a l ittle more prosperous than its neigh­bours, and which affords the prospect of further development in the future. The general depression arises from far-reaching, if not universal, causes; the slightly additional margin of profit is even more valuable than it would be in more prosperous times : it is proof of vitality under stress of ad var­sity. These very condit ions, however, wliich govern and insure the continuance of good will as a valuable asset, are a snare and a temptation to so regard it after its value has passed away. Every egoistic feeling of the proprietor or manager (and most men cherish them) will combine to show t hat workmanship, discipline, commercial insight, and market reputation are as good as of yore. It is impossible to lay down any rules for dealing wjth such a danger ; it cannot be reduced to any mathematical term. It can only be said that good will is some­times a valuable asset, and that ic is undoubtedly liable to depreciation ; that the reasons for its value, and also for the loss of value, are very subtle, and dependent on the conditions of each particular works; and that the owners are much more likely to over value t han to under value it.

The same reasoning will apply when the goodwill is built up by the owners in the progress and de­velopment of a business, and not acquired by good­will. In this case, however, it is undoubtedly wrong to include it in the balance-sheet, not merely because it is an exceedingly unstable asset, but also on account of the inherent temptation to regard it too kindly. Patterns have before now been used to assist in the dl claration of a dividend ; goodwill would prove a much greater boon to an impecunious board in an e1nergency of the kind. A record of it may, however, be kept with advantage for t he private information of the management, apart from the fina~cial books of t?e c?mp~ny, and this despite the dtfficulty of esttmatmg 1t. The very endeavour to grapple with the. problem wi11 be a useful object-lesson to the manager in the general progress or decay of his factory.

DIAGRAMS OF VALUES AND DEPRECI ATION.

Diagrams are now so constantly used by engi­neers for all sort s of purposes that it appears almost superfluous to say that they may readily be applied to valuation purposes. It must, however, be remembered that the diagrams which the board and managing engineer require should exhibit the final result of the annual valuations, and not be compli­cated with details of the calculations by which they are arrived at. We have previously suggested a method of making and recording such calculations : they may, of course, be made in graphic form, but as they are useful also for book-keepi~g purposes, ~nd may, and indeed ought, to be available for p~1me cost purposes it is far better to keep them 1n a form underst~od by clerks and auditors, and wh.ich is consonant to their ordinary methods of reasonmg and practice. It is, however, desirable that the diaarams should exhibit the change in values of the

0 various sections of the assets, as well as that

in the total assets. But to exhibit these changes on one diagram will lead to so mat;ty interesting and conflict ing lines as to render 1t more of a Chinese puzzle than a workable and useful plan. This may be avoided by having different sheets, say, for :

Land. Buildings and wharves. . Steam engines, boilers, and furnaces. F1xed

plant and machinery. Small loose plant, patterns, and tools.

Horses. P reliminary expenses. Goodwill. General summary. The annexed forms will probably be found to

answer the purpose desired, and the Tables whi~h follow show the amounts, assumed for deprema­tion, or additions. I t will be u_nderstood ~hat these amounts will, in actual practiCe, be ?btan~ed from the schedules already referred to, and 1n whiCh

E N G I N E E R I N G.

it is desirable to record not only the money value of the additions to plant, &c., but either by de­scriptive note, or reference to other books, some particulars of the improvements made, or the new m!lchines purchased or constructed.

The first diagram represents fi xed plant and machinery, purchased or erected in the closing months of 1880 at a cost of 8000l. The deprecia­tion has been fixed at 200l , that is, forty years' life ; but it must be remembered that the amount of depreciation must not be an arbitrary amount, taken eit her by percentage, or a term of years, over the whole amount of plant and machinery, but the sum of the several items written off in the machinery schedule, after due consideration of the conditions of each machine. At the end of 1885 the annual depreciation has reduced the valuation to 7000l., and in 1886 400l. of new machinery is purchased,

iOl l--~>;i,u1

'lt )/)

~200

FIXED PLANT & NACUINERY

[Nov. 22, 1901.

increasing it to 7400l., from which, however, 200l., the year 's depreciation, has to be written. In the following year the annual abatement has to include the new purchases, and it is therefore increased to 210l., being at the same rate as we havo previously assumed. This, howover, is a mere assumptivn, and in actual practice the sum must be obtained from t he schedule in preciseJy the same manner as the original abatement. I t will also be observed that the diagrams only show variat ions in hundred~ of pounds ; but it wiH be evident t httt in a work­ing factory they should be ruled in divisions of not n1ore t han 10l. , p referably less. In 1888 a further addition of 600l., and in 1890 of 1000l., was mnde to fixed plant and machinery, the annual amounts for depreciation being C')rrespondingJy increased. These variations are represented on the di,tgram by three lines. The top one, c 'mmencing

ZOT1 201 9fl .

'35 f,OII Ii'i:.

TOTAL FACTORY'

~--~=i700 - 18.1/:J

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.__£ii00..:;~ :t)o uu

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uoo ~ '00

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u NOTE. IN THE DIAGRAMS FOR USE '- 1--+-t--1

t=~7~00=t=t=t4tt=tj=~~=t=t==t=t=~~==+=·~7~: H4t:.~ Ll N£S SHOULD BE EQUALLY ~~~ · e_ ·n I'Uif ~"' rl'f 1.::> OF e 10 OR I ~ <;sft-+--1-i--1 400 800 xuu -lllll

F ixed P la;nt and Maokine1·y.

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- ·---·--at 8000l. in 1880, and ending at 6700l. in 1895 (the actual amount should be 6680l.) is the vary .. incr value of the plant year by year. The left­ha~d bottom line, commencing at 200l. ~tnd ending at 3020l. , exhibits the depreciation written off from the commencing date, 1880, whilst the r ight- hand bottom line shows the successive additions which have been made. The difference between these two li11es will exactly give the varying valu 9 line at the top of the diagram. 'Ve have thus three points brought under the notice of the manager : first, the present value of the plant and machinery, with a graphic delineation of its variations, starting from its first cost : secondly, the amounts which have been suc­cessively debited to revenue for depreciation thereon, with their total at the present time ; thirdly, the expenditure on replacements ? r addi­tions to plant, with the several dates at whteh tlH·y occurred.

Year.

1881 18 2 1883 1884 1835 1886 1887 1888 1889 1S90 1891 1892 1893 181)4 1895

Year.

Value, Janu:u y 1.

£ 8,t00 7,800 7,600 7,400 7,200 7,000 7,200 6,s:IOO 7, :380 7,165 7,930 7,680 7,430 7,180 6,030

110,876

J anuary 1.

Deprecia-tion. Add"t' I Value, 1 tone. December 31.

£ .e £ 200 •• 7,800 200 •• 7,600 200 • • 7,400 200 .. 7,200 200 •• 7,000 200 400 7,200 210 •• 6,990 210 000 7,380 225 • • 7,155 226 1000 7,9RO 260 •• 7,680 2oo •• 7,480 260 • • 7 180 21i0 •• 0,930 250 •• 6,680

8320 £0l0 I

109,655

T otal Faoto1·y.

Dc>preoia-• t 100.

Vulue, Additions. December 81.

Value, 1

1 --- -- ----1------1------1881 1832 1883 1884 18 5 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895

£ 24,000 23,400 22,800 22,200 2l,600 21,000 21,000 20,585 20,765 20,125 20 885 20,210 19,735 19,055 18,775

£ 600 coo GOO coo 600 600 6'6 620 640 6,JO 675 675 680 680 680

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600 2 0 800 ..

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400 • •

£ 23,400 22. 00 22,200 21,600 2l,OOO 21,000 20,585 20,765 20,125 20,885 20,210 19.735 19,0!l5 18.776 18,095

1---- '----·----- - ---316,135 I P505 3600 Sl0,230

The sum of several such diagrams is given in our second one, and this should be either com~iled from or checked by them. The whole of the fac­tory, including goodwill, cost 24,000l. in 1880, and the depreciation first written ~~ was 600l. _per annum, increased by the provtston for varwus additions to 680l. per annum. In 1886 400l. was spent on additional machinery, and 200l. on a new boiler : in 1887 new sheds wet·e erected at a cost of 200l. : in 1888 600l. was spent on mA.chinery, and 200l. in extensions of buildings ! in 1890 1000l. appears for n~\~ mach~ory and ~OOl . for overhaul­ing and repa1rmg e!l~mes : wlnlst ~892 and 1894 witness further add1t10ns to the mot1ve power and other facilit ies of the works. The net result is thn.t the total value of the buildings and appurtenances, which cost 2-11 000~ . in 18807 havo cleprt-ciated to

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Nov. 22, rgor.J E N G I N E E R I N G. - . - ea

SUCTION HOPPER DREDGER; SEINE NAVIGATION.

CONSTRUCTED BY THE SOCIE rE ANONYME DES ANCIENS ETABLISSEMENTS SATRE, LYONS AND ARLES.

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18 0951. in 1895. This r esul t must not only agree with the detailed diag rams, and the schedules from which t h ey are compiled, but should also be iden­tical with t he a mount stated in the balance-sheet of the company, if the manager's valuation has been adopted for financial purposes.

'l'h ese diagrams do not represent the cond ition of a prosperous engineering factory maintained in the highest state of efficien cy ; but they p oin t out more clearly than such an instance would t h e constant drain which an efficient rate o f deprecia­t ion causes. Mr. Ewing Matheson, in his example, assumes that the or iginal 8000l. has been brought up (during thirty yea1·s) to 19,040l. by additions and renewals, '' t he money being applied in threo ways- i .e., to the renewal of worn-out or obsolete plant by purchasing new, the price obtained on re­sale of the old going to diminish the expense ; to the renewal of important parts of old plant, or the enlarging of machines so as to add to the e~~ning capacity ; and, lastly, to t he purchase of add1t10nal plant, eith er to supersede manual operations, or to extend the ou tput of the factory. , The r ate of depreciation allowed (5 per cent.) brings t he value down to 8073l. at t he end of 30 years . N ow it is eviden t that the maintenance of t h e value of tho machinery, and, indeed, of all the ot her plant and buildings, depends on a. la.vish expenditure for r enewals and extension s, and that only by constan t e fiorts a fter improvement can t he works avoid rapid and proba bly increasing deterioration. This fact cannot be too constantly or e mphatically brought un der t he notice of t he management , especialJy when it is remembered t hnt competing and yo unger firms will readily adopt all improved

·and h.bour-saving m achines.

(To be contmued.)

NEW SATRE DREDGERS FOR SERVICE ON THE LOWER SEINE.

THE lower reach of the Seine, from Rouen to the opon sea, had, unt il recently , been practically unused for ma ritime service, although it might have been m1de a. first-class channel for commercial purposes . Navigation, as far as Rouen, was carried out under very great difficulties, owing t o the varying nature of the water d ischarge a.cd the chsngin~ depths. U p till 1848, of the 78 miles which separate Rouen from the sea, 37, at least , formed an estuary of exceedingly great width, useless in the point of view of naviga· tion, the fairway being a. shallow and very change­able one, in the midst of shift ing sandbanks and mud. In the period from 1848 to 1866 a series of longitu­dinal dykes were built on both banlcs, the total developed length of which rapidly extended to oYer 40 miles; these gave good results in the sense t hat they deepened the channel at many places. From 1866 to 1885 no new work was carried out, and the m"'intenance in good state of r epair of the dykes previously bnilt- with unsuitable material - was very Ja,boriot}s. Sin re 1885 al. tempts have been mn<.le to

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improve the conditions of navigation up · stream from the Risle River, and the conditions of the estuary proper. The object is to regulate the distance between t he opposite banks in such a \Va.y that the body of water available is t he largest possible, dredging being re~orted to in order to in~­prove the flow and deepen the channel. In 1895 a powerful bucket dredger was put in service ; t his was found very efficient, in that it easily reduced to 3 ft. under the zero of the charts, beds that were formerly above zero. As soon, however, as an experi· meutal suction dredger had been t ried and found to give excellent r esults, the Seine Board of \i\7 orks ordered t hree powerful ones of this system from the Societ e des Anciens Eta.blissements Satre, of Lyons, Aries, and Rouen.

There being very often rough weather on the Lower 1 eine, and as there could be no question of putting the dredgers in shelter when not in actual \VOrk, they had to be built seaworthy throughout. They, in fact, travelled under their own steam from Marseilles to Hav re, having been built a t Aries, in the South of France, and behaved perfectly well in the crossing. The details and principal dimensions of the dredgers in question are given in Figs. 1 t o 6 (see page 705 and our two-page plate). Fig. 7 is a view reproduced from a phot ograph, and Fig. 8 a view of t he engines (eee page 714). The hull is divided into compartments by eight watertight bulkheads. The first con1partment is the forepeak, used as a hold ; the second one is the crew space, with berths for eight men. The next compar t ment contains the officers' cabins and one cabin for the Ponts and Chanssees engineer, who ha~ charge of inspecting and supervising the work done. In the following compartment are th.e sand and mud well~ , the normal capacity of which is 17,658 cubic feet, the maximum capacity being 20,483 cubic feeli, when extension tops are put round the openings of the hoppEP"s, which is possible in fine weather. The wells are seven in number, fitted with two pairs of doors or sluices. The next compartment forms the engine-room, and also con tains t he dredger pumps; the one next to it is the stokehold, with coal bunkers, the last one being the chain looker.

T here are in each dredger t wo vertical compound en~ines, capable of developing together e. t otal of 540 indicated horse-power at 150 revolutions. This type of engine has been buil t in large numbers by Messr$. Satre for various purposes. Their principal dimen­sions are the following :

Diameter of high-pressure cy-linder ... .. . ... ... .440 m. (17lil in.)

Diameter of low- pressure cy-linder . . . .. . . .. .. . . 800 , (31! , )

Sbroke ... ... ... ... .450 , (17g , )

They are surface-condensing ; the condenser is placed horizontal, and forms part of t he engine frame. The valves are easily accessible for inspection and main­tenance in good working order. T he engines are so at ranged tlu"t they can readHy be made to drivt',

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together or separately, both the propellers or the pumps. The boilers are Belleville boilers, fitted wi th economisers of 2154 square feet heating surface, wit h two donkey pumps, and with an air compressor of 8830 cubic feet. A fresh-water tank can supply the boilers during a oontinuolls run of 75 hours ; suitable apparatus are provide-d for filtering t he feed-water taken from the drain-pipes and condensers.

Each dredger is driven by two propellers worked from the engine sha fts through couplings. The propellers are independent one of the other, and can t urn inversely, this being rather a. novel feature for this kind of craft .

The dredging device consists of two centrifugal pumps worked from the main engine. The pump shells are cast in one piece, and provided with man­holes for removing all obstructions when necessary. The suction turbines have four blades, and contain a special arrangement which prevents the sand from penetrating between t he blades and the inside walls of the pump body. The door-pieces on the front part of the pumps carry the suct ion neokP, which are con­nected, t hrough an elbow that r uns through the deck and a horizontal conduit , to another neck; t he latter is fitted to the suct ion pipe through another elbow, a flexible length of tubing and a. Hooke's joint. The suc­t ion pipe can draw sand from a depth of 43 ft. below water level, and can work even during a rolling swell of 19 in. The joint with the suction pipe being level with t he deck, all work of maintenance and repair is easily carried out. The discharge from t he pumps is effected through shoot s, each with seven openings, provided with sluice doors to regulate the delivery on the d redger. Hoppers of perforated plates are pro­vided iu the sand wells.

Double steam winches are placed on deck a.t both ends ; t hese are supplied with steam from an auxiliary boiler. Another steam winch serves to work the sluice valves and the suction pipe. The auxiliary boiler in question is multitubular, and supplies not only the winches, but a lso gives steam for the electric lighting of the boat and for heating the various berths. The electric-lighting equipment serves to facili tate night work; three arc lamps of 1000 candle-power each are provided on deck for this purpose.

These dredgers give full satisfaction. They were to draw each 17,658cubic feetin 50 minutes; their travelling ~peed in a rolling swell of 15 in. was sp eci fied to be 8 knots, with a. coal consumption of 1.87 lb. per indicated horse-power per hour. During the tests, the wells were filled in 38 minutes; the speed reached was 8~ knots, with a coal consumption of 1. 70 lb. only.

'Ve hear that the Societe des Anciens EtablisEements a.tre have recently booked an order for seven

similar suction d redgers for the Monte Video Harbour W orks.

?yfonE.PRESSED STEEL C~ns.-Tbe Pibtsburgh and Lake Ene Ra.droad Company w11l shortly place an order with the Pressed Steel Car Company for 1000 additional steel hopper. bottom coal C!l.r~ .

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B I I

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--·

Fig. 2 .

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£

THE

SHIPBUILDERS' ANGLE-BEVELLING MACHINE.

W E illustrate on page 702 an angle and Z ·bar bevel­ling machine made for Mesera. Palm er and Co., of J arrow, by Messrs. Davis and Primrose, of the Etna Iron W orkE, Bangor-road, Leith. The machine is of a type specially suited to large shipbuilders, as it greatly facilitates t he execution of all the open and shub bevelling needed. Where this is done by hand, the workman has, in the first instance, to guess at the angle, and frequent alterations are usually required before the work is right. This often leads to the bar being worked too cold, or, in extren;te cases, to t~e bar having to be heated three or four times. The rask of damage to the ~teel is t~us con~iderable, .and, i.n the end, ft~.ir work 1B not easily obtamed. W1th this ma.· chine- which, as shown, is motor driven-all these risks are avoided. The machine is brought in front of the furnace, and it then draws the bar out, bevels it out from the heel, and smooths down the rough edges of the rivet boles, leaving a fai r job, which will lie close t o the plating when put in place. The opera· tion is effected by rollers whilst the bar is hot, so that local straining of the edges of the bar is avoided. The time occupied is, moreover, so shor t that after the bar leaves t he machine it is still hot enough to be bent t.o the curve of the frame wi t hout reheating. Angles, Z. bars, and some sizes of chaune~· bars can be operated on with equal ease. In settang the machme the bevels a.re taken from the body plan of t he ship a.t equal intervals along the bar, a.nd the angle at each number or spot is measured and transferred to th~ cor­responding angles of ~he ~evel b?ard.. The bevelmdex with which the machme I8 provided 18 graduated from 90 deg. to 45 deg. , and the angles ~!lrked on the be~el board a.re set in turn on the bevelmdex of the machme in their proper relative positions, measuring from t he end of the bar.

PERSONAL AND T RADE NoTES.- We a.re asked to state tbatl the recen t! fire &b the works o£ Messrs. B. Rhodes and Son brassfounder8 of 234 and 240, Bow-road, London, E ., 'was confined 'to . a coml?arati vely ~mall porti<?n of the premises, and wall nob mterfere wath t~e b~sm~s, which is bting oa.t r ied on as usua1.:-Electr10 L1ghbmg Boards Limited. have transferred their sales nepar tmentl to 9, G~osvenor Mansion~, Victori~-sbreeb, S, W,

E N G I N E E R I N G. [Nov. 22, 1901.

DAVID COPPER PROCESS. (FoT Desc?-iption, see Pa(le 708.)

FtgS

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600 IIORSE-POWER COMPOUND ENGINE AND ELECTRIC GENERATOR.

W E briefly not iced in our issue of June 28, 1901, the compound engine built by Messra. ~Iarkham and Co., Limited, of Chesterfield. On page 703 will be found illustrations of the above engine, including a vertical section through the low-pressure cylinder and frame. As remarked in our previous notice, this engine is an example of a British-built engine, on the lines as laid down by American practice, for the generation of electric energy for t ramway purposes, and it was the only example of this type of plant on exhibition at Glasgow. The engine is a vertical cro~s compound Corliss engine of 500 indicated horse-power, designed to run at lOO revolutions per minute, and having cylinders 18 in. and 36 in. in diameter by 42 in. stroke.

The flywheel and generator, the latter of which was built by the British W estinghouse Company, Limited, are mounted on the crankshaft, occupying the space between the two engines. A receiver of suitable capacity lies along the back of the trunk frames, and is connected by suitable pipes to the cylinders. The receiver is arranged with reheating apparatus for the purpose of drying and reheating the receiver steam. Galleries are built ou the frames and are connected by stairways, band-railing being provided where necessary.

Reynolds's Corliss valve gear is used, and is designed with double wrist plates, giving a range of cut-off from 0 to . 75 stroke. The trip gear on both high and low-pressure cylinders is controll~d bJ: a Por~er governor, arranged to handle the engmes wit~l a varaa­tion of not more than 1~ per cent . The pistons are built with a removable outer periphery, which con­tains the packing rings, so that, when cylinder re­boring becomes advisable, the. P.iston can be increased to suit the new bore a t a m1n1mum of expense and trouble.

The crossheade are fittei with adjustable shoes, having a. wearing face of 20 in. by 10 in . , and lined with Babbitt metal. The back of the shoes are wedge shaped, and slide on inclined surface~ formed on the cross head casting, and are " set" for the cor1 ect posi­tion on the crosshead wedge-face by means of adj ust­ing screws. The slide paths ard bored in the frames to 24 in. in diameter.

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The crosshead pins have 6!-in. by 6~-in. journals and are removable, t hus enabling the builders to use a solid-ended connecting-rod at t his end. The crank­pin end of the connecting-rod is of t he bolted strap type, with journals 7 in. by 7 in. for crankpin.

Both ends of the connecting-rod are fitted with boxes cast of a suitable bronze for wearing purposes, and are a.dj ust able by means of a. wedge block and screw.

The cranks are of the disc type, made of cast iron. They are balanced and polished a ll over. The crank ­shaft is 17 in. in diameter at the flywheel and gene­rator seats, and is of ample size to withst,and the great and erratic variations of stress due to the nature of the duty which a plant of this description has to meet. The flywheel weighs about 37,000 lb., of which 26,800 lb. is in the rim. It is in halves, strongly bolted and hooped together.

The trunk frames are of graceful outline, of substan­tial construction, and are well ribbed. They are super­poEed upon a. bedplate of deep section, the holding­down bolts passing through and fixing both frame and bedplate. '£he main bearings, which are 14 in. in diameter by 24 in. long, are formed in the bedplate, and are fitted wit h t op and bottom removable boxes lined with Ba.bbitt metal. These boxes are so design(d that by easing the weight of the crankshaft they may be conveniently removed from their places. Arrange­ments are made round t hese boxes for a water-cooling service. The engine t hroughout has been designed with a view to efficiency, substantial proportions and ample bearing surfaces, and convenience of manipula­tion and access, and may be taken as a good example of Brit ish workmanship in a field hitherto almost ex­clusivelv occupied by t he American engineers.

The electric generator is of 325-kilowatt capacity, and was built direct on the crankshaft of the engine we have just described. This generator is constructed according to standard Westingbouse designs, and is of the direct-current shunt-wound type. The field consists of a circular yoke, into which are cast the internally projecting pole-piece~. The field coils are wound and insulated on sepa­rate formers, then slipped on the pole-pieces, and secured by lugs a.nd eet-screws to t he field ring. The field ring is vertically divided, and provisions are made whereby the halves of t he field may be easily drawn apart on guide-plates iu a horizontal

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direction. The armature core is built up of soft-steel ?tampings, held together by oast-steel end-plates. It 1s wound on the drum principle, the windings being so arranged that the coils are formed and iosulated, and afterwards placed in the core slots without any bending or hammering. They a.re secured in position by fibre wedges driven into notches in the slots above the conductors. A peculiarity of the armature winding is the method adopted for securing magnetic balancing. Additional connections are made between points of the armature windings, w hi eh are nominally of equal potential. Any want of balance in the coils is taken up by a flow of current through these addi4

tional connections, instead of passing by way of the brushe~. Perfectly sparkles1 running is thus secured. The armature and the commutator are both built on one cast-iron spider. The commutator end-connections are thus perfectly rigid; and should it ever be necessary to remove the armature, this can easily be done wi.thou.t disturbing the connections in any way. The sp1der 1s travers'3d by cored passages, and the core discs and windings are so spaced that a constant stream of a~r is forced round the machine windings by the rota­tiOn of the armature, and exceptionally cool running and big overload capacity are the results.

This generator was running as a motor on a 500.volt direct-current circuit, the current for this purpose being supplied by a Westinghouse gas·driven set. The Markham engine, being turned through its operating cycles as load for the 325-kilowatt generator, was shown to foil advantage.

THE DA VID COPPER PROOESS. ALTHOUGH the metallurgy of copper has advanced

during recent years, further simplifications appear desirable in several respects, and so far the often­attempted adaptation of the Bessemer process to copper had failed. It is noteworthy that in the very year when Bessemer succeeded in making steel djrect from pig it occurred to several metallurgists to treat copper matte in a converter in a similar manner. Among the earliest patents which aimed at this direct production of copper we may mention those of Gassage, Baggs, and Keates, and many other n9.mes could be quoted. Holway, it may be remembered, at any rate succeeded in obta.ioing a white matte. Most of the other attempts ended in practical failures, and the Royal Institution of London agreed that the con· verter did not appear to be suited for turning out metallic copper.

It had, howe,rer, been introduced into copper works, but without sufficient modification to yield practical results. A decided transformation was required. The converter had preserved its well-known shape of a cy lin· drical recipient with vertical or horizontal axis, and a system of lateral tuyeres, admitting the air blast at a slight dept h below the surface of the metallic bath. Of this kind was a Bessemer apparatus for the metal· lurgy of copper, patented in 1880 by Mr. ~1anhes, a French engineer. The process was adopted or tried in the Eguilles Smelting Works, near Sorgues, in the Department Vaucluse. The managing director of the3e works was ~fr. David, the inYentor of the charac· teristic novel process which we will presently de­scribe. On the .Manhes plan, the ores were first smelted to matte in furnaces ; the liquid matte was then introduced into the converter, and the blast turned on; under abundaet evolutions of sulphurous acid vapours, the ~etallic copper began to collect in the lower part of the converter. A copper with 1.5 per cent. of impurities resulted, which could easily be refined. In the United States, where converters are applied on a grand scale, experiments have been made with lower pressure blasts, and particular attention has also been paid to the preservation of the converter lining, which is subject to rapid corrosion ; sand and silicious minerals have been injected through the blast pipes, and basic linings have been tried.

Mr. Da.vid, the director of the Eguilles W orks, had all the more reason to devote his ingenuity to the im· pr0\7 ement of the copper converters, as he has to deal with raw materials of extremely varied types. As a rule, the converter copper is both auriferous and argentiferous; but refining in a reverberatory furnace does not eliminate all the substances which are likely afterwards to disturb the electrolytic separation. For this reason particularly he gave the practice of t he Welsh smelting works a trial. In Wales, the im­purities of the metal are concentrated in the ''bottoms " of comparatively low density, which are separately treated in a reverberatory furnace. It occurred to the inventor to produce these bottoms directly in the con­verter. In countries where fuel is expenai ve, the converter is more economical than the smelting fu rnace, and the task was to produce, in one operation, both tha bottoms and a purified copper in its metallic state.

Success, it need hardly be stated, was attained only after a large number of more or leas fruitless experi­ments. Mr. Dd.vid first had the idea of fixing the tuyeres horizontally at a certain level above the bottom of the converter, with the object of confining the blast to the matte; while the metttllic copper

E N G I N E E R I N G. [Nov. 11, 1901. -THE BARROW HEMATITE STEEL WORKS.

( F'o1· Desc?·iption,, see Page 710.) •

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would sink to the lower space beneath the tuyeres as it was being reduced from the matte. The metallic copper would thus not be exposed to the cold blast, and not tend to cool rapidly. Unfortunately, this apparatus did not answer, especially not with low­grade mattes. In their case the operation had to be repeated. The first blast had to produce a superior matte of 60 or 75 per cent., which had then to be sub­jected to a second treatment. For a.s the tuyeres were stationary, care had to be taken tha.t a sufficient amount o(metal 'vas always covering the lower portion of the converter, so that the unreduced matte should be raised to the proper level within the blast zone.

Mr. David therefore constructed a horizontal cylin­drical converter whose tuyeres formed a cylindrical generatrix. That arrangement permitted of changing the level of the nozzles during one and the same opera· tion, so that the cold air struck only the matte, but neither the metallic copper nor the slags. This proved successful within limits. As long as the ores were free of certain constituents, notably antimony and arsenic, a good copper was obtained; but with their presence a mechanically inferior copper resulted. As now these very constituents are characteristic of auriferous and a.rgentiferous copper ores, something better had to be found, not to lose these valua.ble by-products, which the practical metallurgist cannot waste.

The solution of this difficult problem has been found in the special converter which Mr. David dis­tinguishes by the term "selector." The principle is that of the extra. process of the Welsh smelting works. When a complex sulphide ore, containing nickel, anti· mony, &c., is being oxidised, the reduction should proceed in the inverse order of the affinities of the different metals for sulphur, which we know form their heat of combination with sulphur. That is to say, gold should first be reduced, and copper last. As a matter of fact, of course, the process does not follow such simple lines. Copper is continuously reduced; but when we fractionate this copper as it is being formed, we find in the first portion all the gold, together with a little of the antimony ; in the second all the antimony, together with other metals; and, finally, we draw off pure copper containing only a little silver. Chemical analysis of a mineral will tell us how much copper we must separate by the &rat fractionat ion in order to make sure of removing all the elements which impoveriP.h the copper.

The David selector allows of repeating this separa­tion as many times as we desire without interrupting the process, and thus exposing the fused matte to cooling. The selector is made spherical for various reasons. The spherical form combines the greatest capacity for a shell of a certain area with the greatest strength ; the fireproof lining can best be applied, and will wear uniformly. The converter is a sheet-iron retort lined with refractory earth, and provided with a mouth, through which it is both crarged and die-

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chargtd, and which further serves as an outlet for the gases. The box, also of ~heet iron, for the tuyeres is fixed into the lower portion of the selector. The air arrives through the axis C and through the curved conduit D (Fig. 3, page 706), on which the gearing for turning the converter is mounted. The bottom of the box E is provided with orifices; a. perforator is passed through the holes to force air passages through the lining in the proper direction. The level of the nozzles lies a. little higher than the bottom of the vessel. To the one side of the converter is fixed, by means of bolts which can easily be removed, a. spherical dome, also made in sheet iron and lined Jike the whole converter. This dome forms a pocket which communicates- or communicated, for a simpler con· struction is now applied- with the interior of the vessel by a. passage. There are two openings in the pocket. Through the first it is cleaned and the port is opened or closed ; through the second opening, a t a. lower level, t.he metal is discharged. Theee mani­pulations are carried out with the help of the gear R (Fig. 1 ).

The joint with the air-supply pipe requires par· ticular care. It comprises a flexible steel tube which can take up the concussions of the converter due to the agitation of the heavy liquids and solids, and is packed with leather. The tuyeres do not pro­ject into the interior, nor is there any need for keeping them open by special means, as they are inclined and grouped like generatrices of a hyper· boloid. Under the influence of t he oblique cur­rents issuing from the air passages, the whole mass assumes a gyrating motion, and the matte, thrown obliquely against the wall of the converter, sinks down again. This brisk gyration of the mass keeps the air passages unobstructed, as already pointed out, and clearing is only required at the beginning of the operation, when the mass i<J still cool; but t he con­verter need only be inclined for this object.

Recently Mr. Da.vid has considerably simplified the const ruction of the selector pocket, which will occupy the lowest position of the selector, when the vessel is inclined the opposite way in which it is held fol' pour· ing out the charge. The rather complicated pocket above described is now reduced to a truncated cone, from the smaller base of which the discharge passage starts. Clay is rammed into this passage to close it·, and the passage is reopened with the aid of a steel rod,

The selector rests on a frame of U-shape and turns about a hollow axis when passing through the different operations of a cycle . The diagram Fig. 1, page 706, explains the mechanism. The worm w hi eh engages with the toothed wheel fix£d on the hollow shaft is turned by a. crank. The whole converter travE'ls with four wheels on two rails, and can thus be brought up to the smelting furnace to receive its charge and returned to its position under the chimney

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Nov. 22, 1901.] E N G I N E E R I N G. •

TilE BARROW HEMATITE STEEL WORKS.

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hood, which takes up the fumes ; these fumes pass through condensing chambers before they escape into the atmosphere.

The rammed refractory lining is an agglomerate of quartz and a little clay; it is dried with the aid of three or four coke stoves, which heat the mass to red glow and convert it into a. fireproof covering.

The following lines briefly describe the various operations of the process, which are indicated in the seven diagrams of Fig. 5. The minerals or mineral mixtures, to which suitable fluxes are added, are brought into the furnace; t he flux is of the ordi­nary kind, calcareous or eilicious, according to the nature of the gangue. The whole mass melts, the sul­phides sink to the bottom, and the slags float on the top. The slag is tapped off at intervals of 20 minutes, and finally the metallic sulphides-the ma.ttes-are run off into the mouth of the selector through an inclin€d

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conduit of sheet iron, protected by a. fireproof lining. When the selector is full, the tap-hole is closed, and the conduit withdrawn. This is the first operation.

For the second phase the selector is returned to its normal position under the chimney, and the flexible air pipe is attached. The reactions commence im­mediately. Clouds of white fumes escape; they consist of sulphur dioxide and of the vola.tile oxides of metals like zinc, lead, &c. The iron combines with the silica of the lining to · a. basic silicate. This silicate is very fluid, and floats on the matte; its formation and its oxidation are powerful sources of heat. The temperature rises rapidly during the first stages from 500 deg. to 1500 deg. Cent. and the mass soon becomes white hot, in spite of the cold blast passing through the fluid. The beat is not due to the sulphur, for as soon as the sulphur begins to be burned, the ~mperature goes down. It is the silicate which

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binds the oxyg~n, and one might indeed say that the iron plays the part of the fuel, and acts as combustible. This view is quite in accord with recent researches on the corn bustion of metal@. Soon the sulpbide3 of the other metals (not copper) will be oxidised, and the fumes become brighter ; the flame, originally a t rans­parent red, due to the combustion of iron sulphide, turns into a. light blue. At this moment only iron silicate and copper sulphide will be left in the selector, which musb then be emptied without delay. For otherwise the liquid would boil over and be ejected from the converter; a tumultuous seething gives timely

• warmng. We come to the third phase, the pouring-off of the

slag. This slag, which is white hot and liquid like water, is removed by tilting the selector, and received in cast-iron pots, running on two wheels. The opera­tion must be conducted with care not to allow the

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N OV. 2 2' I 90 I. J E N G I N E E R I N G. wards lowered by the usual counterbalanced beam con- rams, worked from an eccentric shaft, which bring suffi­trolled by a rack and pinion arrangement. The ores cienb force upon the pigs to break them, the broken pieces emelted consist of both local and best foreign hemabite, fa1ling into a receiving wagon placed under a shoot on the usually containing (SO per cenb. of metallic iron. T he other side of the ma.cbine. coke u ed is principally obtained from Durham and Mixer.-The mixer (Figs. 3 and 4, p9ge 707) was the £rsb Lancashire, and from the company's own collieries at receptacle for this purpose erected in bbis country having Baros.ley . . The limestone. is p rocured from the company's mechanical movement. It has a capacity of 120 tons of quarr1es, s1t~ated b.hree m•les from nhe furnaces. The blasb- molten iron, nearly 6000 tons passing through ib weekly. furnace slag 1s run m to self· tipping bogies (Fig. 6, page 707) The iron is conveyed by a locomotive from the mixer to and baken by uarrow.gauge locomotives to the tip situa~ed , the Bessemer shop in ladles of 18 ton~ capa.citv.

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f\boub half a mile from the furnaces. The gases from the furnaces are utilised for heating the stoves and boilers.

Breaker.-Tbia mechanical device for brel\.king pig iron ha.'3 jusb been introduced (Fig. 6, pa~e 709}. It is placed upon a massive concrete foundation 13ft. 6 in . high, and is actuated by electric motors. The pig iron is cast upon the pig bEds in the customary mann~r, and when cool is pick~d up by means of a steam travelhng crane and placed upon wagons. These wagons are all taken to the machine, where an electric travelling crane lifts the comb of iron on to the breaker girders, between which the feed table reciprocate3. The machine is then pub in motion, the tavle rises, and the comb is carried forward under breaking

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RAIL MILL .

Besse1ner Shop.-This is one of the most modern of European Bessemer shops, and contains four converters, each of 20 tons capacity, arranged in one row, and facing what is generally kno\vn as the pit. T he convertera are elevated sufficiently to allow the ladle, standing on a crane below, to receive the contents of steel, and also to allow a bogie on a road beneath the converter to receive the slag. Eaoh converter is actuated by means of a power­ful pair of vertical hydraulic rams having a rack-and­pinion acting in oppostte directions. In front of the con­verters is a. platform, SU{>ported by iron columns, to which access is obtained by an mclined road wa.y, along which the molten iron is brougbb from the mixer m ladles (Fig, 7,

7II

page 709). The locomotive places the ladle of iron in front of the mouth of the converter, a. hook engages itself on to a pin fa~tened on the ladle, and lifts it up gradualJy until the whole of its contents are {>Oured into the converter. When the ladle is emptied, it 1s again lowered on bo the carriage and returned to t~e mixer to be re-fil~ed. . .

Spiegeleisen is cha.rsed mto the converter m a stmtlar manner, the cupola bemg ab the one end of the platform and on the same level as the converter.

The converbers are attended below by two transfer cranes (Fig. 8, page 710), on which are placed the ladles for receiving the steel. These cram~s transfer the .ladles .to a centre or casting crant-, from wh10h the hea.t lS cast mto moulds. In addition to the ladle cranes there are two smaller ones, which ser ve for changing the ladles or any obher .Pit work. All these cranes, although of different sizeP, are of the same principle, viz., the top supported pillar having a. wheel actuated by a ram and rack for the turning movement. This is a very simple arrangement, and is found t o work admirably. The cranes are worked from an ordinary distributing-box, from which the con­verter and lifbs a re also worked.

All the moulds are placed on bogies, ea,{)h bogie carry­ing two mou lda. They move forward under the nozzle of the ladle a<J required, the centre crane remaining sta­tionary. The bogies are moved along by means of a finger fixed on a. ram, which is sitJUated on the floor level. Each mould is made to hold 2 tons of steel, and in order tbab the arrangeruent of casting should work well, about a hundred bogies are always in ust-, the consequence being that there is a constant stream of bogies and moulds in circulation, and by keeping them running in proper order, the moulds become cool by the time they are requi red without recourse to water-cooling.

When the ingots have remained in the moulds ten minutes, the bogies are drawn forward to the ingot stripper. This is a. very useful machine, which, with a. minimum of labour, strips the moulds from the ingots and places them on to an empty bogie that they may re turn to the yard to cool before being used again. The ingots still on the bogie, but stripped of their moulds, are baken to two gas-heated pits by a small locomotive. These gas-fired pits bake the form of a long passage or channel 5 fb. 6 in. wide and 6 fb. 6 in. deep, an either end of which is a set of regenerators. There are five lids to each pit, and they hold twenty ingots, that is, four in~ots under each lid or door. The doors or lids are of oast Iron lined with bricks, and are supported by girders, on which the four wheels of each lirl run during the openin~ and closing. These doors are moved by a rack and pmion, actuated by a small hydraulic ram, there being a clutch for each door. Each pib is served by a amall crane similar to the serving cranes in the Bessemer shop, but wi th the addition of a racking-in motion.

When the ingots ara sufficiently heated, they are taken oub of these pits by the same hydraulic cranes, and are placed UJ:On a brain of live rollers, which convey them to the cogging mill.

Cogginq Mill.-This mill (see Fig. 9) is a. 36-in . train driven by a. pair of high-pressure horizontal reversing engines, having cylinders 42 in. by 48 in, and geared 2 to 1. The rolls have five grooves, and the screws are fibted with a rack-and-pinion movement actuated by a ram, which lo wers the rolls 2 in., so that the bloom re­ceives a draught of 2 in. in passing through and returning. \Vhen the bloom has passed through the last groove of the oogging mill, ib runs on roller gearing to a. shears where the rough ~nds are out off. This prevents collars and other troubles arising during subsequent rolling.

Roughvng Mill.-After shearing, it pa&es in a straight line to the roughing mill. This mill consists of a 28-in. train and is driven by a pair of high-pressure horizontal reversing engines with cylinders 50 m. by 64 in., and working direob. In usual work a bloom makes five passes in this mill and then proceeds to the finishing mill.

Finishing JlfiU.-This mill (see Fig. 10) also is a 28-in. train, and the engines are similar to those ab the roughin~ mill, except that the cylinders are 48 in. by 54 in. There are five grooves here, after passing through which the bar proceeds on live rollers to the saw, where it is cub into the requisite lengths. After sawing, each rail is placed on the hot bank by means of skids, of which there are four pair~:~, one pair for ea.ch bank. When the ~ails are cold they pa,ss on roller . gearing to the £nish­mg bank, where they are straightened, drilled, and fiuished in the customary way. 'l'he mill is capable of easily producing 6000 tons per week.

Siemens Melting Shop.-Thereare four Siemens furna{)es of 60 tons capacity (Figs. 11, 12, and 13, page 722), one of 36 tons and three of 20 tons capacity. They are of the ordi­nary design, producing about 1600 tons of steel weekly. Tbe gas for the Siemens furnaces is generated from a range of thirty-six ordinary Siemens gas producers. There are three coal-fired horizontal heating furnaces for the slabbing mill arranged in semi-circular order, the curve being struck from a centre on which revolves an hydraulic charger and d.rawer. This oh~rger rec~ives the ingots from the pib­stde crane, and w1th ''ery httle manual labour attends to the charging and drawing of the furnaces.

Slabbing M iLl.-The heated ingots are nhen conveyed by a small locomotive to the slabbing mill, where they are rolled to any desired size, and cub (by means of a me­chanical shears) into the necessary len~ths to suit the order specified, and conveyed to the plate mills. The mill is driven by a pair of htgh-pressure horizontal revers­ing engines having cylindera 36 in. by 42 in., and is geared 3 to 1. The train is 36 in. with a lift of top roll of 16 in. balanced by hydraulic rams. The screws are driven by a pair of small engines.

Plate M ills.-There are two plate mills; the first is drh:en by a. p_air of h~gh.pressu~ehorizont!l-1 non. condensing en~mes, havmg cylinders 60 m. by 54 m. The train is 28 m., and consists of two pairs of rolls, each 7 H. 6 in. long,

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and rolls plates from 1 in. to 2 in. thick. The slabs are heate~ by four ordinary coal-heated furn aces served by a ohar~ng a!ld drawing machine similar to that a.b tJbe slabbmg null. There are live rollers on both sides of the rolls and a skid arrangement to convey the plates from the soft to the hard rolls. The plates when cool are con­veyed to the shears by a steam travelling crane having a. ~an of 70ft.

The second plate mill is driven continuously by a vertical. beam engine of. a.~ old type. The soft rolls are three h1gb, 9:nd the fimshmg are two high, the rolls in both cases bemg 6 ft. long and the brain 26 in. This mill receives slabs about 4 in. thick, and rolls all orders re­oe~ved w~ic~ are ~oo tJhin for the large mill, viz., from l m. to ! m. m clus1 v~.

JJfe:ohar~:t Mill.- This mill has a.n 18-in. train Qf roll:J, a:nd 1s dr~ven by a.. pair o.f horizontal engine3 with cy­hndera ~3 m. br. 48 m . It 1s used for the rollin~ of fish­plates, hght rails, angles, ba.l'f!, &c., from 4-in. billets.

T ram-Rai? Mill.-This is driven by a. pair of high­pressu.re horizc;m tal rev~rsing engines, with oy linders 42 in. by 48 1~., ha~ng CorllSs valves, and is geared 3 to 1. The m~ll c_onsists of two pairs of rolls and is a 28-in. train. The mtll IS also used for the rolling of girders, angles, channels, sole-plates, &c.

Fotl!nd-ries.-The foundries, of which there are five nam~ly, _three for the production of steel castings, one fo~ makmg m got moulds, and one where all the brass castings are made, are well equipped with stoves and powerful cranes, the former serving tlo oast, and the latter to after. wards lift, the hea.vi~sb stern frames, rudder frames, rolls, !l'nd other large oastmgE~.. The small steel foundry, which 1s used for the product10n of small steel castings, pos­sesses a 7-ton Siemens furnace, having a. Duff's gas pro­ducer alongside.

R_oll-Tu rning Shop.-Tbis shop has nine lathes, and js d~Igned on the best known principle. It is provided with an overhead rope t ravelling crane which runs the whole length of the shop.

E11,gineering Shops.-These are extensive, and comprise the machine shops and subsidiary shops, viz., the boiler, smiths', wagon-building, saw-making, and pattern-making shops, &c., and saw mills, all containing fine tools of recent date. It is in these shops that the machining and finishing of the marine castings takes place, as well as the construction of all the firm's own new work, and

• repa.ue. Eleotrioal I nstallation.-This consists of two dynamos,

each giving 750 amperes ab 220 volts, driven by two vertical non-condensing engines and one dynamo of 300 amperes at 120 volts, driven by a horizontal engine, which also drives the shop machinery. These three dynamos supply the necessary electricity for 1500 incan­descent lamps, 130 arc lamps, 12 motors, and the electric welding.

General. -There are 60 steam boilers in use ab the iron works, and 105 at the steel works(one is indicated onFig.14, page 723), and 15 broad-gauge and 15 narrow-gauge loco­motives employed. The wire works is situated ab a short distance from the steel works, and contains a. rod mill and tJwo hoop mills. Other departments of the works are the general offices, laboratory, drawing-office, testin~­house, stores, &c. The total number of hands employed 18 about 3500, exclusive of those at the coal and iron mines, which are extensive, and about 250 at the wire works. The area. of the land occupied by the company's works, including railway sidings and reservoirs, is 245 acres.

~IESSRS . R. H ORNSBY AND SoNs, L unTED.-The direc­t ors of Me~srs. R. Hornsby and Sons, Limited, Gra.ntham, recommend a dividend of 6s. per share on the ordinary share:a, free of income tax, placing 5000l. to the reserve account, and carrying forward 1284l.

Russi AN METALLURGICAL I NDUSTRY. - The Russian For~e Ma~ters' Association has just published some statlStics of the production of pig iron and steel in Russia during the first half of this year. The production of pig iron is returned ab 85,677,900 poods, as compared with 87,867,300 poods in the first haJf of 1900 (62 poods = 1 ton). The production of Soubbern Russia. in the first half of this year wa'3 44,573,400 poods, as com­pared wi th 44,227.100 poods; of the Oural, 25,573,300 poods, a.s compar€d with 26,849,100 poods ; of Poland, 9 183,800 poods, as compared wibh 7,668,100 poods; of the Moscow district, 6,387, 700 poodEI, as comp~red with 7,428,000 poods; of N orthern Russia., 945.600 poode, as compared with 1,125,900 poods ; and of South-Western Russia., 14,200 poods, as compared with 69,100 poods. During the last five years the blast-furnaces of Southern Russia have more than doubled their production, but for the last three half-years there has been a certain check in affa.irs. This check is observable throughout Russia, the production of the first six months of 1900 remaining in­ferior to that of the first half of 1900, as is shown by the figures which we have just given. The production of pig made its first great start in Russia in 1877. Io amounted in that year to only 23,036,571 poods, but in 1886 it bad been carried to 3 l , 578,495 poods. In 1887 it f urtber ad va.nced to 36,410,149 poods, and it then increased rapidly and continuously until the output for the whole of 1900 was 176,778,672 poods. As a consequence of the great increase in home production, the impor ts of pig into Russia declined in the fl rst half of th1s year to 438,000 p oods, as comparPd with 1,358,000 poods in the fi rst half of 1900, and 3 032,000 poods in the first hal f of 1899. The imports of iron into Russia have also considerably declined, having recrded to 2,626,000 poods in tho first half of 1901, from 2, 905,000 pood:J in the first half of 1900, and 9,091,000 poods in the first half of 1899. The imports of steel, again, declined to 433,000 poods in the first half of this year, as compared with 705,000 poods in the fi rst half of 1900, and 1,254,000 p oods in the first half of 1899.

E N G I N E E R I N G.

NOTES FROM THE NORTH. GLASGOW, Wednesday.

Glasgow Pig-Iron Market.-The warrant market was steady las~ Thursday forenoon, hub very idle, only 1500 tons cha.ngmg hands. Cleveland, to which the busines3 was confined, improved 1d. per ton, to 43s. 3d. cash buyers. Scotch warrants were quoted 2d. per ton better ab 543. 5d. sellers one month, while Cumberland hematite iron was nob quoted ab all. Aboub 5000 tons of Cleveland was done in the a.fter~:10on, the price finishing ab 433. 5d. per ton cash, being a gam of 3d. on the day. Scotch warrants were nob quoted. The settlement prices were: Scotch, 54J. 6d.; CJleveland, 43s. 3d.; Cumberland hema.tite iron, 58s. per ton. . Business was done on Friday forenoon in Scotch Iron at 54s. 9ld. p er ton, in Cleveland ab 43~. 5~d. cash; and none was done in Cumberland hema­oi te iron. In the afternoon business was only trans­acted iu Cleveland iron ab 433. 5d. per ton cash. The settlement prices were : 543. 9d. per ton, 433. 4ld., and 58s. 4! d. per ton. A fair amount of business was done in the warrant market on Monday forAnoon. Some 7000 tons were sold. Scotch was bid for from London, and made 1s. per ton at 55s. 6d., and Cleveland fell ~d. per ~on. I~ the afternoon about 10,000 tons changed hands, mcludmg 2000 tons of Cleveland ab 43s. 4~d. per ton three months, and prices were very firm . U p bo 55s. 9d. per ton cash was paid for Scotch, and Cleveland was l~d. per ton dea.rer than ab the forenoon c!ose. The settlement prices were : 55s. 7~d., 43s. 4~d., and 58s. Gd. per ton. The markeb on Tuesday forenoon ws.s steady, with, however, not very much doing, the turn­o 1er nob exceeding 7000 tons. Scotch warrant~ further improved 1~d. per ton to 55s. 10~d. cash, but Cleveland was a shade off ab 43~. 4~d. cash per ton buyers. Cumberla.nd hema.tite iron was dealt in at 58s. 4d. per ton cash. About 1000 tons changed bands. In the course of the pay 2165 tons of hema.tite pig iron were landed a.b Grangemouth fromStettin. Thesettlemenbprices were55s.l%d.,43s. 4~d., and 58~. 4~d. per ton. The market was full this forenoon, and aboob 7000 tons were dealt in and ab easier prices. Cleveland only was dealt in. In the afternoon only some 4000 tons changed hands, and the settlement prices were: 55s. 9d., 43s., and 583. l i d. par ton. The following a.re the quotations for No. 1 makers' iron: Clyde, 66s. 6d. per ton; Ga.rtsherrie, 67s. ; Langloan, 69s. Gd.; Summer lee, 71s ; Colbness, 7ls. 6d. per ton-all the foregoing shipped at Glasgow; Glengarnock (shipped ab Ardrossa.n), 66s. ; Shoots (shipped ab L eith), 703.; Carron (shipped at Grangemouth), 67s. 6d. per ton. American advices have again come s trong and etocks have been re­duced. '£he number of Scotch blastfurnaces in operation is still 83, a-s compared with 80 at this time last year. One has been changed during the week ab Clyde Iron Works from hematite to ordinary iron. The week's transactions have been chiefly in Cleveland iron. Pro­bably 50,000 tons changed hands in the course of la.sb week. M essra. Connal's stocks stood las t night ab 56,612 tons, as against 56,726 tons a week ago.

Sulpkate of Ammonia,- Thia commodity is in brisk demand, and the price f.o. b, a.t Leith ranges up to lll. 5s. per ton. Almost every iron works in Scotland is now making sulphate. There are, perhaps, two works that are nob yet fittf d up for collecting the gas and extracting the ammonia as sulr.hate- Ca.rron a.ud Ardcar, in Ayr­shire, close by Nobels explosive works.

Coal Trade of the West of Scotland.- This branch of trade continuP.s to be very well employed, and prices rule firm all round. House coal is in good demand, with prices unchanged. Stellm is unaltered, both 8.9 regards pdce and the amount of business doing. Splint gives evidence of la.r~e outputs, and is still plentiful, but producers of this class of coal show no disposition to modify their quotations. E ll is ab present in much request for e xport, especially the better qualities, and the price is, if any thing, a shade higher. Treble and double nuts are being got rid uf with freedom, more so, perhaps, in the cage of the latter class, and price3 are sbeady. First-class dross and single nuts have ample outlet for home consuruption, and the pric3 keeps very firm. All other classes of small stuff are in rather better request ab slightly improved prices. The quotations for shipment at Glasgow may be taken at about the following rates. Steam co~l, 9~. 9d. to 10s. per ton; splint, 10~. 6d. to 11s.; ell coal, 10~. 3d. to· Us. per ton, according to quality.

I nsti tution of Elect1·ical Engitneers: Glasgow Section.­The opening meeting of the new session of this institu­tion took place last night. Professor Magnus Maolean, F.R S.E., chairman of the section, presided, and there was a large attendance of members and associates. The chairman bad the honour of presenting to Mr. M. B. Field, the chief elec-trical engineer to the GlMgow Corporation tramwa.~s, a prize which had been awarded by the parent institut10n in London on account of a paper read by Mr. F1eld lacst session. Subsequently the chairman delivered an address, in the course of which he referred to the Nernsb lamp, which is now in actual running in Scotland. Mr. '\;Va.Her Jamieson occupied the rest of the evening with a verbal com.munic~tion on. "High Fre­quencies," the apparatus bemg chiefly deVlsed and con­structed by himself. Currents up to 120,000 volts were experimented with. Mr. J a.mieson was awarded a. very hearty vote of thanks, and on the motion of Mr. Mavor, a.n exceedingly cordial vote of thanks was awarded to the chairman.

West of Scotland I ron and Stul Institute.- La.sb Fri­day evening the second meeting of the session of the West of Scotland Iron and Steel Institute took placeA­D r. William Jacks, President, in the chair. The prin­cipal business was the discussion of two pa.perR on "Water- Softening '' and "Water· Purifying," which

[Nov. 22, 1901.

were held as read from the opening meeting by Mr. J. A. Clark and Mr. P . A. G. Bell, both of whom attended to take part in the discussion.

NOTES FROM SOUTH YORKSHlRE. SHEFFIELD, Wednesday

Sheffield University College. - The council of the U ni­versity College, Sheffield, have decided to erecb buildings to house all the various departments in St. George's­square, in order that the college may adequately carry out its work. This, it is estimabed, will involve an ex­penditure of 90,000l. The sale of the old college will, it is expected, realise 27,000l., and a further 40, OOOl. has already been promised. Speaking ab the annual meeting of the governora of U niversiby Col­leges, . held on Tuesd~y, Sir J. T. Mappin, M.P., referrmg to the Techmcal Department, said thab the needs of Sheffield manufacturer3 and student3 urgently demanded a magnetic sub-department; that a small low­pre3sure Bessemer plant, and a. small hammer-shop wi th forging, an~ealing, hardening, ~nd t empering appliances should bela.td down. These thmgs were a necessity. No ane who was aware of what was being done in Germany in electrical engineerin~ would fail to see that the college was insufficiently accommodated for teaching electrical subjects. As regarded the metallurgical section, the question ha.d been raised whether operations should be confined, as heretofore, to one metal-steel, or whether they should launch out in other directions as well.

Half-a-Millio'n, for Electric Light at Sheffield. -On Tuesday Mr. A. A. G. Maleb, A.M.I.C.E., one of the inspectors of the L ocal Government B oard, h.:>ld an inquiry into the application of the Sheffield Cioy Council for sanction to borrow 500. OOOl. for purposes of the electric-light undertaking. The town clerk stated that the demand for electricity was rapidly overtaking the supply, and it was now necessary to establish new works. In 1893, when a. private company had possession, the number of electrical unitls supplied was 131,006, and for the fifteen months ending March 25 last, 2,381,000 units were used. Mr. Fedden, the manager of the department, stated that the proposed new station would contain three 1500-kilowabb alternator sets and a. spare boiler. Each boiler would be about 1500 horse-power, so that the total power of the plant would be 6000 horse­power. The total sum of 500,000l. includes 136,000l. for exten.sions on the present station, and for extensions of mains. The new works at Neepsend were roughly esti­mated to involve an expenditure of 238,000l. , and 10,500l. is allowed for the projected arc lighting scheme for 100 lamps. Contingencies are placed at 31,000l. , and a further sum of 83,000l., completing the half million, is to cover expenditure already incurred.

Iron and Stecl.- The decrease in the quantity of work on hand in the heavy departments of trade shows no sign of being checked. The falling off in the consump­~ion . of Bessem.er, Siemens, a~d ot~er open-hearth steels IS sttll proceedmg, and there IS no 1mmediate prospect of improvemenb. Manufacturers of railway stores are short of v:ork, and the companies are placing orders very spa.rmgly.

South Y orkshire Coal Trade.-During the week the de· ma.nd for house qualities has increased, both locally and for Lo?don and the Eas tern counties. Prices are firm. Best sllkstones make from 13s. to 14s. per ton; Ba.rnsley house 12:3. to 12J. 6d. per ton ; and nuts from 10s. 6d. In the steam coal market, although there is plenty of cor­rent business on hA.nd, there is no Rtrong feeJing as to the future. Values are maintained, Ba.rnsley bards making from 93. 6d. bo 10s. per ton. There is a very strong de­mand for gasmaking qualities, a.nd engine fuel of a11 kinds sells readily. Nuts are quoted a.t 9s. 6d. to 10s. per ton ; screened slack from 5s. 6d. per bon; and pit slack from 2s. 6d. per ton.

NOTES FROM CLEVELAND AND THE NORTHERN COUNTIES.

MIDDLESBROUGH, W edneaday. The Cleveland Iron Trade.- Y esterd a.y the weekly

market here was numerously attended; but business was quiet, and quotations for Cleveland pig iron were weak. At the 2a.me time, however, there were one or two traders who reported that there was rather mora doing than at the previous weekly gathering. Sellers were in no great hurry to do business, and were most reluctant to reduce quotations; whilst, on the other hand, buyers were backward and were only dis­posed to make purchases sufficient to meet their early requirements, so that it is not ab all surprising tra.nsao· tions were on a limited scale. Both makers and mer­chants were prepared to sell N ~. :3 g. m. b. Cleveland pig iron at 43s. 9d. for prompt f.o. b. delivery, but they would nob, as a ruJe, entertain offera at anything below that price. Transactions were recorded at the foregoing quotation, which was regarded as the general market rate. No. 4 foundry and grey forge were each 433. 6d. ; mottled, 43~, 3d. ; and white, 42~. 9d. East Coasb hematite pig was in good request., and the supply was still insufficient to meet the requirements. Nos. 1, 2, and 3 were firm ab 60s. for next month'd delivery. Rubio ore was steady at 153. 9d. ex-ship Tees. To-day prices were practically unaltered.

Ma;nttfacttll,.ed Iron and Steel.- The manufactured iron and steel trades are, on the whole, steady, and thongh new orders are scarce, producers of most descriptions have a good deal of work on hand, and they are unwilling to lower the rates that have ruled for some time past. At the same time, there is no doubt that a good contract might be made below market quotation3. Common iron

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N 0 V. 2 2' I 90 I. J bars are 6l. ~3. ; be~b bar~:~, 6l . 15s. ; iron ship plates, 6l. 17s. 6d. ;, u on sh1p-angle.13, 6l. 53.; steel sbip·plabes, 6l. ; ste.el ship·angles, 5l. 17s. 6d. ; and heavy secbtons of et~el rail~, 5l. 103.-all less 2~ per cent. discount, except rails, whiCh are net cash at works.

Coal amd Coke.-Fuel keeps steady. Good Durham gas coal is 11s. 9d. to 12~. 6d. f.o.b., and unscreened bunkers which are very plentiful, lOa. 9d. to lls. 3d. The demand for household coal is better than it was but it is still only moderate. Coke is not plentiful eno~gh to meet re­quirements, o.nd quotations are very strong. Average olastfurnace qualities are 163. 9d. delivered here and coke for shipment is 18.!. and upwards f.o.b. '

JAPANE E CONTRACT l<'OR RAILWAY MATERIAL.­Tenders were opened at the Government Railway Office Tokyo, on October 18, for a number of engineering re~ qairements, and amongst which was an inquiry for 1246 tons of fishplates, 72 tons of steel bolts and nuts, 4~ tons of look washers, and 256 tons of spikes. The bulk of the stuff had to be delivered either ab Y okohama or Kobe and about one-third of the whole at Sa.kai, a port on the' west coast of J apa.n, necessitating transhipmen t in Kobe or Nagasaki. The remit of bbe tender was as follows:

£ Messrs. lilies and Co. .. . . .. ... 14,339

., T akata . . . . . . . . . . . . 14,562 The China and Japan Traditig Company 14,988 Me3Sr3. Mi tsu i . . . . . . . . . . . . 15,477

: 1 Okura ... ... ... ... 15,647 , J ardine . . . . . . . . . . . . 15,855 , Isono . .. . . . . . . . . . 16 379 , Birch . . . . . . . . . . . 16, 4 U

The order wa~ taken by the lowest bidder, and placed with Krupp. H eretofore these orders have gone either to America or England. Of the merchant firms tender­ing above, the first is a Gerwan firm, and is supposed to represent Krupp in Japan; the second, fourth, fifth, and seventh n.re J a.panese, the third is A merican, and the sixth and eighth are British. If an order goes past a merchant firm, it is not the merchant's fault, as the busi­ness is cub by them all to the finest point, competition for this kind of business is so severe. The prices above include bank interest (as the Government does nob pay until after the goods have been delivered into their " go­downs " in Japan, and the goods examined and weighed ), landing chargfs, and merchant's profi t,- but do not include imp01 t duty. The interest might be reckoned ab about 2! per cent. for about 4~ months' use of the money, and the interest on the 10 per cent. deposit made with the Government. The landing charges would be about 48. a ton.

---UNIVERSITY COLLEGE, L IVERPOOL (STUDENTS' ENGI·

NEERING SooTETY).-The third meeting was held on Tues­day1 November 12, 1901, Professor Hele-Shaw in the chair, when a paper was read by Mr. P. H. P owell, B.Sc., on "Elecbrical Safety Appliances," of which the follow­ing is a very brief abstract. Mr. Powell first alluded to the necessity of providing means to prevent live con­ductors charged ab the high voltages commonly in use at the present day, coming into contact with people, and went on to describe one of the first systems in use- viz., that of protecting the trolley wire on tramway circuits by fastening long pie<:es of cane over . ib. ThiS sys~m has many great objec~10ns, most of wh10h, as well as Its general application, being generally well known. Another method was to use guard wires placed above the con­ductor in the same plane, and about 18 in. apart ; these wires ~re sometimes, though nob always, insulated. Mr. Powellsaid he did not eee much use in insulating them, as if a broken telephone wire came in con tact with the conductor as well as the guard wires, it were better that the guard wires should oe _well earthed, :when a sh?rt circuit would result , causmg the fuses m the sect10n boxes to blow. He also described (1) Canter's device. of having the guard wires laid t ransversely under the wue to be protectJed, and lead weights atba<:hed to the t~le­phone wires, causing them to C?~e m contact w_tth the guard wires if broken ; (2) Quirt s system o~ havmg a J?ilob wire lead from the far end of the sect10n suP· phed to the sw.itch-pillar, an~ connected to the ehunb coil on the sw1tch; so that m the event of a stop­page of the current through the coil, the latter allows the core to fall, knocking up a catch and . releasing the switch lever, which is forced out by a sprmg, and thus cuts off the trolley wire Jro!D the feeder. (3) T_he U lbricht earthing method, wh10h depends on the prm­oiJ?le of a momentary connection between the trolley wire and the earth, estJablishing a direct communication between the same, this connection remaining until the apparatus is reset ; ( 4) Messrs. Bosbock and C~eetham's plan of service only in the case of the troll~y wue ~reak­mg, and of which Mr. Powell g~v~ the ~nventor ~ ?a­scription ; (5) Mr. C. if. Mesurter s device, providmg against accidents due e~ther t o. the over~ead conduc~or breaking, or telephone w~res falhng a?ross 1~. A ~escrlp· tion of several brakes was then gt ven, mclud1ng the "slipper " air and electric types ; an advantage of the last~named being that the frequency of stoppage does nob matter as it is the current from the motors driven from the' car itself, which furnishes the brake; the " eddy current and fri<:tion " type of brake, in w?ich there are three different act10ns ab one an4 the same tnme, tending to stop th~ car ; ~nd the W _es.tmghouse brake, which is also of triple act10n, combmmg track brake, wheel-rim brake and axle brake. An elaborate account of the various ty'pes of switches and fuses in use was also given the paper being profusely illustrated throughout. After' the paper had been discussed, a cordial vote of thanks was gi' en to Mr. PowelJ.

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E N G I N E E R I N G.

NOTES FROM THE SOUTH-WEST. Card~ff.-There has been a steady inquiry for large

steam coal at previous rates, hub the market for small coal has been ~omewhat easier. The best steam coal has been making 16s. 6d. to 163. 9d. per ton, while secondary qualities have brought 15s. 6d. to 16s. per ton. F rosty weather is giving an impetus to the house-coal trade ; No. 3 Rhondda large has made 15s. 6d. to 16s. per ton. There has been a. steady inquiry for patent fuel. Foun­dry coke has been firm ab 20~. to 233. per ton, while fur­nace ditto has brought 17s. 6d. to 18J. 6d. per ton. As regards iron ore, ruoio has q1ade 14~. Gd. to 148. 9d. per ton. and Tafna 153. to 15s. 6d. per ton.

South Wales Ooal a•nd I ron. - The exports of coal from the six prinoipal W elsh ports, Cardiff, Newport, Swansea., Port Talbot, Llanelly, and Neath, in October were: Foreign, 1, 768,298 tons ; coastwise, 348,125 tons ; total, 2,116,423 tons. The exports of iron and steel from the six ports for the month were 3753 tons, whlle those of coke were 5473 tons, and these of patent fuel 90,576 tons. The shipments of coal from the six ports in the ten months ending Oobober 31 th is year were: Cardiff, 13 313,382 tons ; Newport, 2,837,038 tons ; S wansea, 1,739,273 bona: Porb Talbon, 358,300 tons ; Llanelly, 221,017 tons; and Neath, 4!>,428 bona; making an aggregate of 18,518,438 tons. The exports of iron and steel from the six ports were : Cardi ff, 23,037 tons; Newp::>r b, 23,600 tons; Swan­sea, 328 tons ; and Port Talbob, Llanelly, and Nea.th, nil: making an aggregate of 47,865 tonE!. The exports of coke were: Cardiff. 50,194 tons ; Newporfl, 18,156 tons; Swansea, 9086 tons ; Port Talbob, 9179 tons ; and Llanelly and N eath, nil; making an aggregate of 86,615 tons. The exports of patent fuel were: Oardiff, 351,012; Newport, 69,691 tons; Swansea, 395,136 tons ; Porb Talbof!, 52,573 bona ; and Llanelly and Port Tal bob, nil ; making an aggregate of 868,412 tons.

A. New I ndusflry for Card~ff.-Messr~. Thomas and William Smith, steel-wire rope manufacturers, of New­castle-on-Tyne, have acquired A. site known as the Old Soap Works, an acre in exten t, at Ma.indy, Cardiff, for the purpose of erecting a. steel-wire rope manufacbory, and also plant for other purposes.

Moumtstuart D1·y Dock.-A new dry dock which the Mountstuarb Dry D ock and Engineering Com\)any, Limited, Cardiff, has been construcbing is now pract10ally completed. The dock, which is 550 ft. long and 66 fb. wide, has been fi nished, and progress is now being made with bbe removal of the cofferdam and jetty, and with the dredging of the en trance channel. The work which remains to be done in connection with the equipment, &c., is expected to be completed by the end of the year. The entrance cuts acroes the former "lay-up " for the pilot boats, and the company has bad to dredge out another place in the East Mud for their accommodation. The dock is the widestJsingle dry dock in the Bristol Channel.

Bute Dry Dock Company.-The directors of the Bute Shipbuilding, E ngineering, and Dry Dock Company, Limited, have under consideration a proposal to issue debenture capital to the extent of 76, OOOl., in respect of the purchase of the Mercantile Pontoon Company, Limited. The Bute Dry D ock Company now owns the whole of the ordinary capital in the Pontoon Company, only the preference shares and debentures remaining unMquired. lb is intended to create 100,000l, capital in debentures, bearing interest ab the rate of 4~ per cent. per annum ; hub the difference between ~be figures j ugtJ mentioned and this sum (24,000l.) will not be issued until wanted for further developments.

P ·wllkeli.-The town clerk of Pwllbeli has received an official intimation of a Government grant of 17,500l. in aid of a projected harbour ab Pwllheli.

SuNDERLAND GRAVING DoOit.-The River Wear Com­mi~ioners have decided to proceed wibh the construction of a graving dock 600 fb. long. The dock, which is esti­mated to cosb 100,000l., is to be leased to Messrs. J. L. Thompson and Sons, a leading £rm of Wearaide ship­builders.

DOVER.-The Prince of Wales' rier, constructed by Sir J. Jackson for D over commercia harbour, is now prac­tically cam plebed, and w~l pr~bably be opened befo~e Christma~. Accommodatton Will be afforded for Atlantic linera which will make D over a porb of call. Electric crane~ are to be placed on the Admiralty pier for dealing with the transference of crate~ on and otf cross· Channel steamers.

I LKESTON Er.EOTRIO TRAUWA YS. -On Tnesday the chair­man of the Tramways Committee of the Ilkeston Town Council accompanied by the ex.mayor and others, com­menced' tramway lines for ~he north end of the borough. Alderman Hunt and several others drove a large chisel into the ground ab the Cotmanha.y terminus of the lines. The ex-mayor said he believed the soheme would be a means of developing the town.

F RENCH CoAL IMPOR'l'S.-The imports of coal into France in the first nine months of bhi~ year were 9,049,?50 tonR as compared with 9 391,420 tons m the correspondmg perl~d of 1900. In the~e totals British c.oal figured for 5,188,810 tons and 5,471,720 tons respectively; B~lgian coal for 2 235,250 bona and 3,296, 400 tons respectively, and Germ~n coal for 592,120 tons and 578,410 tons respec· tively.

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MISCELLANEA. A FOND is being formed in Belfast for sinking boreholea

in the line of the euggeated tunnel between Ireland and Scotland.

The discovery of extensive oil fields in Texas has led to several of the railroads operating in that State taking ateps to equip their locomotives with oil-burning furnaces.

The American Bridge Company has secured the contracts to construcb twenty steel bridges for the Uganda Rail· way. The amount of the contract is about 1,000,000 dole. Several British and Continental firms tendered, but the American Bridge Company nob only offered the lowest terms, but also guaranteed the completion of the contracts in the shor test time.

The traffic receipts for the week ending November 10 on thirty· three of the' princip~l lines of the U nited K ingdom amounted to 1 765,637l., whieh was earned on 20, 153! miles. For the corresponding week in 1900 the receipts of the eame lines amounted to 1,767,239l., with 19,886~ miles open. There was thus an increase of 2398l. in the receipts, and an increase of 267! in the mileage.

T he Camden and Atlantic City run of the Reading Railroad has been mentioned eeveral times in our columns. A few days ago, a train consisting of five oars weighing 210 tons behind the tender, made bhe run of 55~ miles from start to stop in 46~ minutes, the average speed being thus 71.6 miles per hour. Mr. Gibb and other officials of the North-Eastern Rail way were amongst the passengers. The train made the run withou b a stop, but was checked three times. The maximum speed attained was 85.7 miles per hour. The train was hauled by a Vauolain compound locomotive with 7-fb. driving wheels, and 2530 square feet of heating surface.

T he enamel paints whioh have been introduced for protecting from corrosion the ballast tanks of steamships are finding an additional application in the U nited States, where bitumasti-o solution, obtained from Messrs. \Vailes, Dovt\, and Co., Limited, of Newcastle, has been used for protecting the penstock of a turbine wheel. These often suffer badly from corrosion, which, roughening the surface, increases the resistance to the flow of water, and diminishes the output of the wheel. In one case noted by Mr. D . J. Lewis, of South Orange, the enamel paint was sound ab the end of two yea.ra ; whilsb c0ats of red lead and coal tar applied at the same time were found badly scored at the end of a year.

The Board of Trade have recently confirmed the fol­lowing Li~ht Railway Orders: 1. Derby and Ashbourne Light Railway Order, 1901, authorising the construction of light railways in the County of Derby, from Derby to Ashbourne. 2. Bath and District Light .Railways Order, 1901, authorising the construction of light railways in the County of Somerseb, in the City and County Borough of Bath, and in the rural district of B!i.th. 3. Ta.nab Valley Light R ailway (Amendment) Order, 1901, amending the Tanab Valley Light Railway Order, 1898. 4. Mitcham Light Railway Order, 1901, authorising the construction of light railways in bbe pariah of Mitcha.m, in the rural district of Croydon, in the County of Surrey.

It is suggested, in l' / nd/u,strie E leof;rique, that a recent observation of Dr. Emile Bose, of Breslau, may lead to the development of a direcb-rea.ding photometer. Dr. Bose has discovered that if a slightly acid solation is electrolysed for a long period between gold electrode!!, one of the latter becomes covered with a thin layer of hydroxide. If now the electrolysin~ current is stopped, and the electrodes connected through a high-resistance ~alva.nometer, a deflection is obtained, provided that light 1s allowed to fall on the electrode covered with the film of hydroxide. The intensity of the current varies with tbab of the light ; and it is noted that whilst violet light lowers the eleotromoti ve force obtained, red light aug­ments ib.

Writing in l' I ndustrie E ltctrique, M. E . H ospitalier suggest3 that after all the true solution of long-distance electric lines may be found in the use of single-phase alternating currents. T o this end, however, ib is essential that some kind of friction clutch shall be devised which i.s capable of dissipating a.a beat a very large quan tity of energy, since a. single-phase motor having bob an ex­tremely smaJl starting torque, it will be necessary to keep ib constantly running, and start the train by throwing into gear the friction clutch. The main difficulty to be faced is a probable excessive amount of wear. In other regards the system has many advantages. But a single trolley-wire or its equivalent would be needed, a very large starting torque would be obtained, and the sub· station plant would be of the simplP.st character.

SLIPWAY AT L AS PALl!IAS, GRAND CANARY.-F1RRATOl'li: By an undetected printer 's error the style of the builders of the slipway at L a.s Palma!.l, descri bed on page 579 of our issue of October 25, was given as ' 'Hay," Summers, and Oo , in place of Da.y, Summ.ers, and Co., of the Nortbam Iron vVorks, Southampton.

HIGH CAPACITY ROLLING STOOK.-The Leeds Forge Company is building 150 mineral wagons to carry about 32 tons, each for the Imperial military rail ways in the Trans­vaal. The oom~any is also enga ged upon an order from the Caledonian Railway Company for 30 similar wagons; these latter wagons are, however, fitted with three pairs of doors on each side to facilitate unloading. They are supplied with W estinghouse and hand brakes. It should be noted t hat a good many of the early wagons upon the Caledonian system are of a very small type.

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E N G I N E E R I N G. [ N 0 V. 2 2 , I 90 I . . ==~~~~~~~~~~~====================~==~~~~~==~~~~

SUCTION HOPPER DREDGER ; SEINE NAVIGATION. CONSTRUCTED BY 'fHE SOCI ETE ANONYME DES ANCIENS El'ABLlSSE MENTS SATRE, LYONS AND ARLES.

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Nov. 22, Igor.] E N G I N E E R I N G. -~========~============~~~~==~==========================================~ ~

AGENTS FOR ''ENGINEERING." AUBTRtA, Vlenraa : Lehmann and Wen tzel, Karntnerstrasse. OAPB ToWN : Gordon and Gotch . EDINBURGH: J ohn Menzies and Co., 12, H anover-street. FRANOB, Pads: Boyveau and Ohevillet, Librairie Etrang~re, 22,

Rue d e la Banque ; M. Em. Terquem, 31 bia, Boulevard Haussman Also for Advertisements, Agence Havas, 8, Place de la Bourse. ·

GKRlUNY, Berlin: Messrs. A. Asher and Co., 6, Unter den Liuden Frankfur~-am-Main : Messrs. G. L. Daube and Oo. (fo;

Adverttsemen ts). Leipzig : F. A. Brockhaus. Mulbouse: H . Stuokelberger.

GLASGOW : William Love. INDIA, Calcutta.: Thaoker, Spink, and Oo.

Bombay: Thacker and Co., Limited. ITALY : U. Hoepli, Milan, and any post office. LrnRPOOL: Mrs. Taylor, Landing Stage. MANCBBSTKR: John H eywood, 148, Deansgate. NoRWAY, Ohristiania : Oammermeyers, Boghandel, Oarl Johans

Gade, 41 and 43. NEW SOUTH WALES, Sydney: Turner o.nd Henderson, 16 and 18,

Hunter-street. Gordon a.nd Gotch, George.street. QUBB.NBLAND (SOUTHt Brisbane : Gordon and Gotoh.

(NORTU , Townsvllle : T. Willmett and Oo. RO'rl"RRDAM : H . A. ramer and Son. SOUTH AUSTRALiA, Adelaide : W. 0. Rigby. UNITBD STATRB, New York: W. H . Wiley, 4S, East 19th-street.

Ohicago : H. V. Holmes, 1267-1268, Monadnook Block.

VtoroRU, Melbourne : Melville, Mullen, and Slade, 261/264 Oollins­street. Gordon and Gotch, Limited, Queen-street.

TRACTION and TRANSMISSION. (Publuhed on the fi;rst Tuuday in each month.)

PART VIU. NOW R•EADY. PatOB 2a., Net; POST FB.Bll 2s. 4d.

Publlahed ab the Oftlcea of ENGINBBRTMG, 86 and se, Bedford Stree,, Strand, London, W.O.

CONTENTS OF PART VIII. PAn• l PAO~

The Inner Circle . ..... . ......... •. 129

1

& rlln Tmmwnys. Dy J . Z'\cbarln.s 171 The Econom ics of St reet RAilwn.ys. Tbe Krldger Elcctromohlle. By

By the Hon. Robort P. Porter: Comad W. Cooke, M.I . R.E., n .-Rntlld 'l'nm~lt of Now (Pinte XLI. , XT~ll. , nnd Uluatm-

York (Pintos XXXIV. to tious In Text) ........ .. .... ... . 1'11 XXXVIII., nod l llustrnt lon New Locomotive for tbe Control in Tuxt.) .. ........ . ........ l.JO London Rullwny (Plates XJ,JII. ,

H lgh ·SJI{'od Bleotrlo 'l'rnotlon In I XLlV, and Xf.V.) .. .. .... .... .. 180 Germany (Plntes XXXIX., XL., The New Electric Power Plnnt for Md Illustrations In Text) .. ... . 162 the Brooklyu R.o.pid Tm nslt Corn-

Municipal 'l'n\dlni: pnDy (PII\te XLV I.) . ........... 192 (i) By W . Vo.lentlue Ball. ..... 100 I The Uoldsohmldt Procel\8 of Ul By .\ uotber Borough Eng!. £1cotrlc Ran Welding (Plate

rteor ....• . ... . .. .. . ...• ... 1~ XLVII.) ............. . ........ . 185 (k) The NewC~~.~~tle·,li ·Tyne l m - The Croydon Electric T•nmwnys

brogllo . • . . . . . . . . . . . . . . . . . . 166 nnd Lighting System 1 Pla te The !Jn11chester £md Liverpool XL Vlll., nod IDuatrationa In

Electric Express Ra ilway ...... l 6S , Text) .. ...... .. .. ........... .. l SS

NOTICE TO CONTINENTAL ADVERTISERS.

Advertisements from Germany should now be sent through Messrs. G. L. Daube and Co., Frau.kfurt..am· Main. who have been appointed our Sole Agents for that country for Trade displayed Advertisements. Advertisements from France, Belgium, and Bol· land should be sent through the Agence Havas, 8, Place de la Bourse, Paris, our Sole Agents for those countries for similar Advertisements.

We beg to announce that American Subscriptions to ENGINRBRlNO may now be addressed either d irect to t he Publisher, Mr. 0. R. J OIJNSON, at t he offices of this Journal, Nos. S5 and 3~, Bedford­st reet, Strand, London , W.O., or to our accredited Agents for t he United States : Mr. W. H . WILKY, 43, East 19th-street, New York, and Mr. H . V. H oLMBS, 1257-1258, 111onadnock Block, Chicago. The prices of subscript ion (payable in advance) for one year are : For t hin .<~oreign) paper editi.on, ll .. 16s. Od. ; for t hick (ordinary) . RBADlNG OASBH. _Reading cases for containing twenty-six paper e.J1t10n , 2l. Os. 6d. ;, or, tf remttted to Agents, 9 dollars for numbers of ENGINBBRING may be bad of the Publisher or of any tbm and 10 dollars for thick. newsagent. Price 6s. each.

of fire there is the other advantage that for a. given offensive quantity less weight of armour is involved; and as a barbette like that for the new battleships, the Queen and Prince of vVales, carries 315 tons of armour, the additional protection for the 9.2-in. guns and their mountings taxes the displacement capital of the ship designer. But against this there is the serious difficulty with the superimposed system of concentration of weight and of stresses due to the firing of the guns, and the still more important objection that one such mishap as is to be reckoned upon as of frequent occurrence in action may throw out of use at the crit ical moment a larger proportion of guns. It should be a first principle, in anticipating mi~for. t une, to so arrange that the proportion of power thus lost will be as small as possible, consistent with other conditions. From this standpoint the British arrangement is preferable. There are ven­tilation difficulties with superimposed gun positions, and the repah· of the larger guns below is certainly not simplified. It is t rue that one man may ' 'sight" and fire all the guns, but here again there is a con­centration of dependence on one factor, with greater proportion of loss through failure. American naval experts are divided on the merits even after prac­tical experience, and it is just probable that it will be departed from. We have seen it suggested in connec. t ion with ships for a European P ower that instead of having either broadside casemates or a superim­posed posit ion for the placement of such guns as the 9.2-in., t hey should be arranged in barbette~ along the centre line of the ship, between the two m~in gun posit ions. This, if we mistake not, was t ried long ago, before even the battleship became so packed with machinery. Boiler casings, funnels, ship's boats, and the necessary top hamper gener­ally make the idea difficult of realisation ; and questions of stability are also involved.

NOTICE TO AMERICAN ADVF.RTISERS. ====-----=====---====---====-=========-American firms desirous of advert ising in ENGINBBRING are

requested t,Q apply to Mr. H. V. HOLMBS, 1267-1258, Monadnock Block, Chicago, or Mr. WtLLARD a. TYLER, 160, Nassau-street, Room 1910, New York City, from whom all particulars and prices can be obtained.

ADVERTISEMENTS. The. charge for advert~sements is three shilli?~S for . the first

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Advertisements intended for insertion in the cur­rent week's issue must be delivered not later than 5 p.m. on Thursday. In consequence of the necessity for going to press early with a portion of the edition alterations for standing Advertisements should be received not later than 1 p.m. on Wednesday after· noon in each week.

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ENGINEERING can be supplied, direct from the Publisher, post free for twelve months at t he following rates, payable in advance:-

For the United Kingdom . • • • • • • • • • • • . • £ 1 9 2 " all places abroad :-

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through newsa-<Tents are requested to communicate the fact to the Publisher, together with t he agent's na.me and address.

Oftlces for Publication and Advertisements, Nos. 35 and 86, Bedford Street, Stra.ud, London, W.C.

we desire to call the attention of our readers to the tact that the above is our SOLE Address, and that no connection exists between this Journal and any other publications bel.ring somewhat simllar titles.

TRL'BQR.APHIO ADDRESS-ENGINEERING. LONDON. TBLBPBONB NUMBB&-3663 GePrard.

--CONTENTS,

PAOB I PAGB The New Subway in New ~?tea feom th ! South-West 7 1 ~

York City (/llus.) ... ., . . 699 1 l:l tecell a.nP~ .. ...... ; · ... : .. 713 The Instit.ution of Mecha· The Gun ~ower of " ~rshtps 715

nical E'lgioeers .. .. ... . . . 700 r he A.rohtt~ o u a l Stde of ., En~ineering Valuations (Il· En~mePrang . . . . . . . . . . . . · 16

lu.strated) .. . ........... 'i"Ol The E 'ect~ica.l Indu~try .... 716 New Sa.tre DrHigers for Ser - The De&tgmrg of War

vice on the Lower Sdne Vessels . . • .. .... . .. . ... . 717 (Jllu~tl'ated) . . . . . .. .... 706 l Notes .. . ...• •.. .... . . · • .. 718

Shipbuilders' An1d e-BeveJ- Notes from the United ,.. line- Machine ( I llustrated) 706 States : . .. .. :. . . . . . . . . . . t l 9

600 IIorse-Power Compound 0)1roscop1o Ao,t,lOn an~ t he Tracr.iou Engine and Elec· 1 TJ088 of the Cobra (l l-t r lc Generator ( I ll us.) . . 708 ltut-ra~ed) ....... : · · . . . . !19

The David Copper Process Patent s m South Afrtca .... , 20 ( nlustrat~>d) . . . . . . . . . . . 70S Industrial ~otes ....... .. .. 721

Tbe Barrow ITemat ;t e Steel The Electrtftcatton of the Works (Jllu8t1'ated) .. .. 710 bhtropolitan and ~etro-

Notes from t he North .... 712 polit an D!~trict Ratlways 722 Notes from South York- The Balnnc10g of Looomo-

ehire .. ...... .... .. ... ... 712 tives ( Illustra.ted) .. .. . . 726 Notes from Olevela.nd and " EngineE-ring " Patent Re-

the Northern Counties .• 712 cord (lllmtrated) ....... 729

With a Pw!J-Pagt Engtavi11(1 of a SUCTION B OPPER DREDGER i SEillB NJ1 VJG.t1TJO,:V.

NOTICE8 OF MEETINGS. TilE SURVEYORS' l NSTITOTB.- Monday, November 25, at 8 p.m.,

when a. paper will be read by Mr. A. Dudley Olarke (Fellow), en tit led : ''The Fioa.\ Report of the Local Taxation Commission."

SOOIBl'Y OF AR'fS. -Monday, Novem ber 25, at 8 p.m. Oantor Lectures. ' 'The Chemistty of Oonfectionerb' Materiah and Pro· ceases," by Mr. William Jago, F.C.S., F.I .O. Four lectures: Lecture 1.- Wednesda.y, November 27, at 8 p.m. '' Leatbn for Bookbind ng," by Mr. J. Gordon Parker, Pb.D , Director ot the London Leather Industries Researob Laboratories. Mr. Richard Garoett, LL D., C. B., will preside.

TilE iNSTITUTION OF Cl\' IL ENGl!\EBRS.-Tuesday, November 26, at 8 p .m. Paper to be submit ted for discussion : " Train Resist· a.nce," by l\Ir. John A. S. Aspina.ll, M. Inst.. 0. E.

SOCIETY OF CIIE:\IICAL I NDUSTRY: LONDON SECTION.- Monday, December 2, at 8 p.m., at the Ohemioal Societ} 's Rooms, Bur· Jiogton House, Piccadilly. The following papers will be read and discussed : H The Lemon on Industry," by Messrs. Herbert E. Burgess and J. F. Child. ''The Separation of Materials of Different Specific Gravity," by Mr. J. W. Hinc::hley.

ENGINEERING. FRIDAY, NOVEMBER 22, 1901.

THE GUN POWER OF WARSHIPS. THE Admiralty are now preparing for the laying

down of three immense battleships and six. armoured cruisers, the designs of which suggest the trend of naval opinion, especially as to ord­nance. The chief characteristic of both types is the increase in gun power, the tendency being in this country, as well as in America and in some Continental countries, to add to the number of weapons of the first class, even at the cost of the total number of guns. Thus, the three new battle­ships, unlike all their immediate p~edeces~ors, will have in addition to four guns of 12-m. cahbre, an equal number of 9.2-in. weapon~. ~he .larger guns will as heretofore, be mounted 1n pau·s 1n bar­bettes fo~ward and aft, and the 9.2-in. pieces will be placed one on each side of each barbette. This will enable them t o be utilised as bow or stern chasers, but it has the disadvantage that while all four 12-in. breecl'.-!oaders can be used on either broadside, only two of the 9.2·in. pieces can thus be utilised in the line-of-battle. The 6·in. guns which they displace, however werd similarly restricted in their arc of training ' but the effort of the warship designer is directed' not only to secure the highest maximum of gun power consistent with other claims-protectiOn, speed, &c.-but also to so dispose his weapon~ as to en~ure the greatest attack on an enemy, ure­l'pecth·e of the relative posit ions of his ship. Thus it comes that opinion is widely divided on this point of the placement of guns. .

It is purely a. matter for comprormse so as to embrace the least evils. The l Tnited Stat~s naval authorities have tried the system of superimposed turrets with the pair of guns of secondary power over the usual couple of 12-in. breech-!oa.ders; and this arrangement, it will be seen, perm1ts of. that training of all four guns at each en~ of the sh1p .on an enemy on either broadside, wh1ch the Bnt~sh

• design lacks. In addition to this concentt·a.twn I •

There is therefore much in favour of the sepa­rate positions for the 9.2-in. guns in the British ship : they can be more quickly manipulated, with a higher-aimed rate of fire. Their superiority over the 6 in. gun confers undoubted advantage. Firing a projectile of 380 lb., they attain a muzzle energy of 19,494 foot-ton8, and there is no reason to sup­pose that the rapidity of fire will fall short of 3 to 4 rounds per minute. 'J.lhe 6-in. gun, on the other hand, develops 6240 foot · tons with its 100-lb. projectile. Indeed, this 9. 2-in. gun is, for its weight, one of the most effective of weapons ; some assume tha.t it may yet displace the 12-in. gun even in battle­ships-an opinion based on the ineffective work done by the larger guns in the attack on Cerfera's escaping ships at Santiago. But with the very hard - faced armour now constructed, no such change is likely to be made. Effort will rather be directed to wards making t.he guns still more effec­tive by the use of other powders and forged-steel caps on projectiles. In this matter we are not quite so progressive as some other Powers, and objection is still entertained against nitro cellulose powders, which are greatly superior to nitro­glycerine combinations, giving quite 10 per cent. higher ballistics, because in the earlier stages of manufacture, in some foreign countries, there was not uniformity in resul t. This, however, has been c01npletely overcome, and the chief of the Ord­nance Bureau of the United States Navy, Admiral O'N eill, in his annual report just issued, refers to this important question. He says : u The bureau does not doubt the safety of cordite powders, but believes that such powders deteriorate with age, are very susceptible to changes of tem­perature, which affects their efficiency, and are very destructive to the bores of the gun." There is little need to enforce this point ; experience in South Africa has helped to bring the point home. Again, Admiral O'Neill says: ''If the rules which have been established for the inspection and storage of smokeless powder are properly carried out, no trouble or danger will be experienced in the storage and preservation of nitro-cellulose powder. "

The slmo general tendency as to gun power is obvious in the case of the design of our new cruisers. Speed, at one time, was considered the dominant desideratum, and it must ever be an important question ; but, at the same time, the cementation process of hardening the face of armour has enabled the naval architect to clothe the broadside of his high-speed cruiser so as to resist attack with the old-time cruiser guns of 6-in. calibre; and t hus it becomes imperative to equip the opposing cruiser with guns of great penetrating power, even at the expenc:e of the number of smaller

weapons, to provide arxnour protection and speed. The commerce destroyer of a weaker nation natur­ally depends primarily on speed ; but '' our friend the enemy, is, at the same time, adopting a measure of protection which, while it may not render the ship invulnerable, will nevertheless give her a fair chance of maintaining her buoyancy and to get beyond the range of many of the existing commerce protectors. It is true that in the Blake and Blenheim and in the vessels of the Edgar class we adopted 9.2-in. guns ; but in later first-class cruisers of n1oderate displacement., the 6-in. gun has been the heaviest piece ; something of greater calibre, well manipu­lated, with real armour- piercing shell, would defeat the 4-in. or 5-in. hardened armour. Thus the change in our new cruisers is most commendable. They will be fitted with two of the powerful7.5-in. weapons which Vickers, Sons, and Maxim have recently introduced. This will be the first applica­tion of this calibre of gun to the Navy, but it has been well tried both by the Navy al!lthorities and at the company's Eskmeals range. Under service conditions it will develop a muzzle energy of 11,825 foot-tons with its 200 lb . projectile, as compared with the 6240 ft. of the 100 lb. shot by the Vickers, the most powerful of our 6-in. pieces. This doubling of the power of the blow which the ~eaviest guns may strike will give the new cruisers great ad vantage alike in range and in penetration. Not only will they prove effective against a high­speed commerce destroyer, but they may harass a battleship of less speed if without modern armaments ; and it would be easy to name many such ships still on the effective list. A comparison of the eight vessels of the Diadem class, built five years ago, with the new vessels also indicates the progress in gun practice, and also in armour. The Diadems depend upon a 6-in. pro­tective deck, the new cruisers will have 4-in. hardened steel on the broadside, as well as protec­tive decks, although of less thickness. No guns of greater calibre than those of the 6-in. type are mounted on the Diadems, but of these they have 14; the new cruisers of the County class, already ordered, have also 14, while the six now to be laid down will have two of 7.5-in. calibre, mounted respectively at bow and stern for ahead or astern fire, and both for use on either broadside. There are also ten 6-in. guns. As this has been gained without reducing the speed, it marks the new ships of 9800 tons superior to the Diadems of 11,000 tons.

The question of weight is an important item ; but here there is no detraction from the general advantage. The one 7.5-in. gun, with its mount­ing, will not weigh any more than the pair of 6-in. weapons carried on the same training mechanism within an armoured turret as adopted in the earlier County cruisers. It is doubtful, too, if the pair of 6-in. guns will fire a greater number of separate shots than the one larger piece. The distance between the guns is so small that the work of loading, &c., must be greatly retarded by the men getting in each other's way, notwith­standing all the ingenuity which has been spent on the mechanism, and in the arrangement for enabling the one hoist to deliver shot alter­nately to the guns on each side of the ammunition trunk (see page 201 ante). The 6-in. gun has in prac­tice a rate of aimed fire of eight rounds per minute, but this can never be reached in these t urrets. The mechanism of the 7.5-in. gun (see ENGINE"ER­ING, vol. lxix., page 746) has a special loading gear, consisting of a tray pivoted on a bar at one ~ide of the cradle, which is moveable with the gun, and this tray is operated by worm and wormw heel gear, so that at any position of the gun it can be swung into the breech on an axis always parallel with the gun. Thus the 200-lb. shots can be fired at the biO'h rapidity of six aimed rounds per minute; but this does not need to be attained to equal the per­formance of the twin 6-in. sets, especially in view of their higher ballistics and greater range.

THE ARCHITECTURAL SIDE OF ENGINEERING.

ON previous occasions we have advocated the association of an architect with an engineer in the design of structures which, situated within city boundaries, should charm the eye as well as serve the less resthetical requirements of the public. In view of a recent discussion of the matter, however, by Mr. H. H. Statham, F. R. I. B. A. (see The B~uilder, Octo her 5, 1901 ), to which our attention has lately been directed,

E N G I N E E R I N G.

we feel almost inclined to withdraw · the recom­mendation and advise engineers to rely on their own resources till architects are prepared to exhibit a less impracticable spirit. In his search for beauty of outline, Mr. Statham is apparently quite prepared either to contract the water-way of such a bridge as that now building at Vauxhall, or to raise the gradients. In either case the public in general would be permanent sufferers. The first object of a bridge is to accommodate traffic, and we cannot afford to rob the Peter of utility to pay the Paul of art. The latter in short must be content to wait till the demands of the former have been completely satisfied. Architects are slow to admit this, and are not prepared to accept without protest the conditions imposed by the requirements of modern civilisation and make the best of them, whether it be a matter of a plate-glass shop front, or of a sky-scraper in an American city. Both are practically necessities of the modern scheme of existence, and it should be the architect's business to discover in them pos­sibilities of beauty. So far, the architect has done little but bewail the hard fate which has condemned him to live in an age in which a shop­keeper is not content to display his goods through leaded lights, and in which the demand for ~ccom­modation on limited areas has compelled him to accept the steel-framed building. He has, we fear, expended but little effort in the attempt to har­monise the new requirements with his views on art.

In calling attention to the architect's failure to attain his ideals in these regards, we in no way wish to defend engineers' architecture, which is generally at its worst when most pretentious. Gothic and other ornaments are stuck on, which have no organic connection with the structure as a whole. All we can say in palliation is that when architects do come forward, as Mr. Statham has done, to show engineers how their work should be treated, they too frequently show serious ignorance of statical principles, and of the " intention " of the main members of a structure. The suggestion, for instance, has been made that the polygonal outline of the lower chords of the Forth Bridge cantilevers should have been replaced by a curve, thus intro­ducing gratuitous bending strains into these struts, and outraging the eye of every properly-educated spectator. A still worse example is afforded by Mr. Statham's sketches (see The B'ttilder, loc. cit. S'1.11p1·a.) suggesting an architectural treatment of the engineer's design for the Vauxhall Bridge, which is calculated to entirely mask the true character of the structure. Thus he does not seize on its characteristic features - the three hinges- and embellish them, but breaks up the whole of the elevation, arch ring proper and spandrel walling inclusive, into a series of sham voussoirs, giving the impression that the arch ring extends the full depth of the structure between the road-line and the intrados, in place of being in thickness a mere 4 ft. or so throughout, as it actually is. Near the widest part of these sham voussoirs he places great shields, which break up the voussoir lines. Appa­rently Mr. Statham has not grasped the theory of the structure. He expresses the opinion that a three-hinged arch is really a couple of huge cantilevers, whereas nothing could be further from the truth. A three-hinged arch differs from an ordinary solid arch merely in that three points of the line of thrust are fixed, a fact which facilitates calculation, and localises joint action on decentering. Architectural emphasis of these three master points would therefore have been intelligible and proper, but failing this, Sir A. R. Binnie's original treat­ment does not mask the true nature of the design to anything like the extent of Mr. Statham's, and, with all its faults, is therefore infinitely preferable, as the truth is always preferable to a sham.

The main defect, indeed, of the engineer's design is the heavy cornice along the line of the roadway. This breaks into the arch ring near the crown in a very unpleasing manner. This arch 1·ing is the characteristic feature of the design, and should therefore be boldly outlined, with its extrados standing free from confusion with any other prin­cipal line of the structure. The total removal of the cornice in question would therefore be a sub­stantial improvement. Mr. Statham's design, on the other hand, is wholly vitiated by his gratuitous assumption that a three-hinged arch is . really a pair of cantilevers. The total inaccuracy of this idea is easily realised when one rem em hers that

[Nov. 22, 1gor.

~ome p~rtion o~ a .cantilever or bracket is always 1n tenswn, whtlst 111 a masonry arch no tension whatever is admitted in any part.

Again, Mr. Statham appears to think that it would have been impossible to construct the arches in question wholly of granite masonry without alter­~ng the proportion of rise to span. This, again, 1s erroneous. A perfectly satisfactory ordinary masonry arch could have been built without diffi­culty to the same span and rise, and with the same thickness of arch ring. In fact, whilst at Vaux­hall the span is 149f ft. by about 19 ft. rise the Dor~ Riparia bridge at Turin has a spa~ of 148 ft., and a rise of 18 ft.; and, in fact an experimental granite arch was built in the 'sixties at Souppes, with a span of 124.3 ft. and a ris~ of 6. 97 ft., and the settlement on striking was but ~- in. Indeed, with mo~ern arrangements, even very fiat arch('S can be bmlt without trouble arising from the opening of joints in settlement. But steeped in their worship of medi::evalism some architects would seem to have lost touch with pro­gress, even in the matter of masonry construc­tion. In fact, it looks as if architects seldom calculate pressures or get out lines of thrust, but rely entirely on eye-designing. This serves well enough where the work is familiar, and on a small scale ; but, if we may judge from similar experience in structural steelwork, it must in work of an un­usual character lead to an excessive waste of mate­rial. Engineers have no desire to build ugly brid~es, and will welcome the assistance of architects; but the latter, if their advice is to carry weight, must show themselves endowed with a reasonable appre­ciation of the conditions of modern life, and with a sufficient knowledge of statical principles to enable them to grasp the function of, at least, the main constituents of a structure.

THE ELECTRICAL INDUSTRY. AMONG the many matters touched upon by Mr.

C. H. Wordingham in his inaugural address, de­livered last luesday evening before the Manchester Section of the Institution of Electrical Engineers, the most interesting was the condition of the elec­trical industry, and the causes which have rendered it unable to meet the demands made on it. .As every one knows, most of the orders given out dur­ing the past year for really large electrical plant have been secured by American and Continental manufacturers; and the idea has arisen in the public mind that British engineers are not only incapable of constructing such machinery, but also that they lack the skill to design it.

Mr. Wordingham traces this fallacious idea to several causes. First, to our national habit of self-depreciation, which makes us praise the methods and products of foreigners, to our own detriment. Secondly, to the fact that it is in accordance with good business principles for the foreigner to accept low prices in order to get a footing in a new market, and therefore the home manufacturer is often undersold. Thirdly, to over­production and industrial depression on the Con­tinent, which forces engineers there to choose between selling at a loss and closing their works. Fourthly, that the same reason enables the foreigner to promise early delivery. His order-books are bare, and nothing stands before the execution of any order he may secure. Owing to the want of fore­thought of those in charge of electrical under­takings here, the demand is allowed to overtake the supply; and then machinery is called for in great haste, and sometimes is even supplied before the auxiliary contracts for buildings, boilers, and the like, are half executed. All these c~tuses work to the disadvantage of the British manufacturer : although he can turn out machinery whioh cannot be excelled either in design, workman<:hip, finish, or durability.

Mr. Wordingham says that he does not pre3ume to suggest a remedy for this state of things, and then immediately puts forward the heroic counsel that engineers must join hands and combine-not as has been done in many branches of com­merce to raise prices, but to lower them, and RO

drive away the competitors who now menace their very existence. It seeml3 strange to sugge~t a com­bination to lower prices; that is a matter any man can do for himself, and which he must do when he runs out of ordere, or else close his establishment. The manufacturer who refuse3 to do so is simply left out of the competition. Works cannot be extended and tools bought when profits are not

N 0 V. 2 2' I 90 I.] bei~~. made; and it is just the want of greater faCihttes for manufacture at home which lets in t~e foreigner. He has had several years of splen­dtd trade under fiscal protection, and his works haYe grown to an enormous size ; while at the same time the manufacturing processes have become pedected by a succession of orders for the same articles. These are very difficult conditions to meet, but the man on the spot has always an ad­vantag~, and our f?reign friends will not be willing to continue s~pply~ng us at a loss always. Their home depresswn will pass away, and they will tire of a turn-over with no profit.

The subject of the electric industry is bound up with that of municipal trading, and there are many persons who would attribute our backwardness in the former entirely to the popularity of the latter. Mr. Wordingham apparently does not hold this view ; indeed, he has been looked on in the past as one who, up to a certain point, was eager in his defence of municipal privileges. Now that he has severed his con­nection with the City Council of Manchester, he appears in the role of the candid friend, and his remarks carry the weight of one who knows both sides of the question. To begin with, he adopts the definition of the Lord Provost of Glasgow as to the conditions necessary to render an industry a proper one for a municipality to take up. "It must be monopolistic in its nature, must be a necessity for t he inhabitants of the district, and must cause interference with the streets." ''If, , says Mr. Wordingham, "municipalities stop short at the point indicated, and confine themselves to em­ploying plant manufactured by private companies, and using it for the supply only of public necessities, the manufacturing portion of the electrical engi­neering profession, at all events, has nothing to lose and everything to gllin by the establishment of undertakings for which capital is found at a low rate of interest." This, of course, entirely over­looks the fact that the reason why the British manufacturer cannot compete in electrical machinery with the foreigner, is that the latter has already equipped his own country, while the municipalities here were considering the matter, and that it is he who is now in a position to reap the advantage of English cheap capital. However, that is a twice-told tale, and we will not weary our readers by going over the old ground again.

Mr. Wordingham is more interesting when he discusses the inherent weaknesses of municipal management. He puts, first, the liability to an entire change in the constitution of a committee from political reasons. Next, the large size of most municipal committees, which tends greatly to ham{ler the work, and to preclude the prompt action necessary in commercial undertakings, w bile the class of men preponderating on town councils tends yearly to deteriorate. rtien whose business is confined to the keeping of small shops find themselves called upon to direct large undertakings, requiring for their conduct a very Napoleon of commerce. Again, there is a tendency on the part of members of municipal committees to seek to shine as technical experts, often deriving their knowledge from some friend who has a smattering of the subject. These men insist upon interfering with their paid advisers. often marring their care­fullythought-out plans. Lastly, t here is the danger-­and it is a very serious one-of political considera­tions being allowed to influence the policy of municipal trading committees: More especiall.Y is this the case where any questwn of labour artses. Many members are in abject terror of the working­class vote, and will go to almost any length to avoid losing it, with the result that the undertaking is severely handicapped.

The above is quoted almost textually from the address, and is a severe indict1nent of t he manage­ment of industrial enterprises by corporations. It is wonderful that they are so successful under such adverse conditions. The good results they do attain must be ascribed in large measure to the efforts of the permanent officials, whose positions cannot be very pleasant. Having to thread their paths among the suggestions of amateur engineers and electricians, they need a double measure of tact and amiability, and at the back of these a large fund of firmness. A second.rate man would lose all heart under such circumstances, and allow matters to drift to disaster.

Mr. Wordingham takes an intermediate position, in relation to the electrolysis of gas and water pipes, between those who argue that no liability

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rests with the traction companies, except to obey the Board of Trade rules, and those who would fetter them with a load of disabilities. His view is that it lies with the owners of the pipes to prove that the damage is due to electric action, and that when they have done so, the electric interests should bear the cost. This, however, is a matter which is not likely to lead to much trouble in the future, as the growing use of negative boosters and feeders limit the drop of potential below the Board of Trade requirements.

In the matter of schemes for the supply of electric energy over a large area, Mr. Wordingham is not an enthusiast. He sees many difficulties ahead. In the first place, the works do not exist in England for the manufacture of the machinery, and if it be required now, it will have to be ordered abroad. In Germany the banks financed the manu­facturers so liberally that the works grew as fast as the demand, But here that kind of aid is almost non-existent. The banks have other outlets for their money than manufacture, and prefer the quicker and safer trade of bill-discounting. It would be a hopeless task to raise money here for the con­struction of works in advance of the demand ; it is difficult enough to get it when the demand exists. As to the future of the stations when built, Mr. Wordingham is not sanguine. He does not agree that the power factor over a large area, including small and scattered towns and villages, will be greatly better than the individual factors ; and he does not see why a number of inherently unprofit­able towns, when connected by mains, the interest charges on which represent a large proportion of the total probable revenue, will be converted into a gold mine by the use of the magic words '' supply in bulk. 11

We have only been able to notice a few points in this address. It is a difficulty with these compilations that they aa:e generally too long to print in full, and that they cover so wide a grouad that justice cannot be done to them in an abstract. This is the more to be regretted when they deal with subjects of present-day interest, and when the author is not afraid to give his views, and show that he has formed opinions on the subjects of which he treats. In a former address before the same society, when known as the Northern Society of Electrical Engineers, Mr. J. S. Raworth commenced his remarks by saying that mankind wanted more of everything, except of presidential addresses ; and this is certainly true of the majority of those orations. But there are exceptions, and when, as in this case, a President will give the results of his experience, he will always find hearers and readers. We are not of those who would rigidly exclude all debate­able matter from such addresses, for to do that is to deprive them of interest. There are cerbainly plenty of inaccuracies that go unchallenged before technical societies when the meeting is open for discussion ; while in other walks of life it is not customary to confine every speaker to platitudes. If it were, gatherings for speechmaking would become more tedious than they generally are at present. We are often in disagreement with Mr. W ordingham, but he is always worth li::~tening to, for he holds pronounced opinions and knows how to make out a good case for them.

THE DESIGNING OF WAR VESSELS. THE German Emperor, whose versatility as a

universal provider of information has hardly been equalled since the publication of " The Child's Guide to l{nowledge," has been instructing his Admirals and the world at large in the way to design and use·a navy. Our own leading journal, fired by so bright an example, has been directing some of this fertilising educational flood over British fields. At a meeting of the German Society of Naval Architects, the Emperor not only listened to a technical paper ''On the Disposition of Guns in Battleships and the Results upon Naval Archi­tecture," but actually took part in the discussion ; probably an unprecedented thing for a monarch, but the German Emperor is essentially unprece­dented. He treated the subject ((b ovo; going back to the days of galley-ships-of-the-line ; for, a true Teuton, his mind is essentially encyclopmdic. His Majesty worked through the long era of ma&ts and sails, arriving finally at the day of the steam·driven armour-clad. Lessons to be learnt by admirals of modern fleets from the tactics of oar-propelled galleys were impressed; the Battle of Lepanto and Don John's semi-circle appearing in due course.

..

We do not feel we are qualified to give our readers the benefit of conclusions to be drawn from this Imperial disquisition on t~e art ?f destruction i. b?t the prosaic details of shtp design are more within our mental grasp. His Majesty said that the dis­tinctive point of German construction is "that from the first it was our object to secure for na,•al officers who sail and fight the ship the greatest possible influence upon constructors and builders. In fact, we are the first nation that has ventured to place an active navy captain at the head of our Construction Department."

The Emperor appears to have been misle~. in regard to his facts; at any rate, so far as the BrttJsh Service is concerned . The Controller of the Royal Navy, who is sometimes, though rarely, a captain, but generally an admiral, is the he&d of the Con­struction Department at our own Admiralty; whilst at the Royal Dockyards the captains or admirals superintendent are the chief authority. Our Director of Naval Construction and our Engineer­in-Chief are but officials in the Controller's Depart­ment at Whitehall ; whilst chief constructors and chief engineers at the dockyards are subordinate to the rule of the naval officer who is superintendent. The professional officials are subject to the com­mands of naval officers in both instances. As a matter of practice the naval officers have the con­trol of ship design. When the design of the ships of the Royal Sovereign class was got out, the pro­cedure followed was made public by an official document- a most surprising and unusual event. It will be remembered that the military fe~tures were settled at a conference of naval officers, and the duty of putting these features into practical shape was alone left to the constructors and engi­neers.

This is the orthodox method of procedure, and one that is stamped by common sense. The naval officer should, by his training and expe­rience, be the best judge of what is needed to make the most efficient fighting machine. Whether gun-fire, speed, or armour, should preponderate in any given class of vessel, are details learnt through strategy and tactics acquired at sea and by long study of the science of naval warfare, and of the experiments undertaken to ascertain the efficiency of guns, armour, &c. That is the naval officer's business. He does not know, however, to what extent it is possible to combine each of the qualities respectively in one design. All military features mean simply added weight, and the natural laws which govern displacement, stability, speed, &c., are inexorable. The naval architect can interpret these. It is obvious that the ship cannot have ar tillery, protection, and speed in excess. The naval architect can say : "If you must have 20 knots and so much armour protection, you cannot have so many or so big guns. \Vhich will you sacrifice ?" In fa.ct, the naval officer designs the ship, the naval architect works out the details.

'!'his, as we have eaid, is common sense; but what is not common sense is that the admirals, having told the constructors and engineers what they need in the completed ship, should interfere as to the way their instructions are to be carried out. The military design having been settled by execu­tive naval officers, they should stand aside until the ship is built ; and then, if the constructors and engineers at the Admiralty or the dockyards have not carried out the design, it would be they who would be responsible. The controllers and admirals superintendent of dockyards are more than redun­dant ; they prevent those who could really control and superintend taking up their proper positions and due responsibilities. Until reform in this direction is brought about, the Navy will never get ships built efficiently, cheaply, and expeditiously, either by the Royal dockyards or by contractors, and this, in spite of all that committees of inquiry, dominated by naval officers, may say to the con­trary. The sway of the uninstructed amateur can­not be otherwise than pernicious.

The German Emperor, who works as conscien­tiously at arriving at the true inwardness of things as any man in Europe, appears to have an idea of these important facts. "No doubt," he says," the shipbuilder must arrive at a compromise between the conditions of artillery fire, the po,ver of the engines, and the tactical requirements of the naval officers." If His Majesty will carry his convictions further, and determine that the proper and in­structed authorities shall be empowered to carry out the work, he may set a useful example that we shall, perhaps, be wise enough to follow. At the

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meeting to which we have referred, His Majesty, with the true histrionic instinct, which is one of his most valuable gifts, felt that his long and serious speech needed, possibly, some relief ; and he told a little tale which was truly humourous. He explained how his zeal for naval architecture led him to inquire of an old naval officer what the "meta-centrum " was. The officer said "he did not quito know, he believed it was a secret; but if it were placed in the truck at the masthead, the ship would capsize.,

The Times Berlin correspondent, to whose report we are indebted for these details, appears to have considered that the Imperial joke needed journalistic explanation. "For the benefit of those--and there must be many," he adds with undoubted truthful­ness, "who are in the position of His Majesty's captain as regards their knowledge of naval tech­nology, it may be mentioned that the ' meta­centrum ' is a point in an imaginary perpendicular line passing through the middle of a ship, at which that line would be cut by the level of the water " ! We hope Sir William W bite, in the next edition of his "Manual of Naval .Architecture," will take note of this enlightenment of the ignorance of average humanity, and will correct the mistaken description he has incorpor<lted in his work. We think, however, there must be a slight misprint somewhere, for every one knows that the metum­centrum, as made in Germany, is calculated from the equator-we should say the equatum-not the water-line. When not in use it is always placed under the charge of the senior navigating officer of the marines.

NOTES. THE J{RIEGER ELECTROUOBILE.

OF the many motor cars t.hat took part in the Automobile Club run from London to Southsea, on Saturday last., probably the most interesting was the Krieger electromobile. This was not the '' Powerful, " which last summer made the Yery remarkable run fron1 London to Glasgow and back : a record performance which has been carefully re­ported on by Mr. Conrad W. Cooke in the pages of TRACTION AND TRANSMISSION. It was a smaller car that made such a good record in th e London­Southsea run, •and was built by the Krieger firm to the specification of the British and Foreign Electrical Vehicle Company, of 4, Blooms bury­place. The weight of the car in running order is 1 ton 15 cwt., and it took five passengers. The following particulars of the run were taken by Mr. Llewellyn Preece, and will be read with interest :

Stoppin~ and Starting Places. Times.

-Nov. 16

Automobile Olub • • • • 9.87 a.m. Egbam Hall .. • • •• 11.25 ,

)I • • •• • • 11.41 )I

Winchester • • • • • • ~.40 p.m. .. •• • • • • 4.22 , Co3ham •• • • • • 0.0 .,

Dist.ances.

mile~

23

44!

23!

-Speed d per

ur. Ho

mil ea

12

14

13

The total timed distance was 90~ miles, the total time 6 hours 26 minutes, and the average speed 14 miles an hour. 'l'he run from Cosham to Southsea was 6 miles. At the start the voltage was 95, which fell at Southsea to 86, in each case with 30 amperes. A charge of 30 units was put into the cells before starting, and 6 units at Winchester, where the stoppage was made for lunch ; on the journey only the prescribed stoppages were made. 'fhis performance was a better one t han that of the "Powerful," and promises well for the future of the Krieger electromobile, in the hands of the English company.

THE CrTY AND SoUTH LoNDON RAILWAY. The City and South London Railway was the

first deep-tunnel line-the first tube railway­in the world. It was designed by the late Mr. J. H. Greathead, and built, under his supervision, by the shield which he invented, and which has since been used in many other tunnels. Originally it ran from Stockwell to the Monument, that por­tion being opened in 1890. In February, 1900, a portion of the line was temporarily abandoned, and a new line was constructed from the south side of London Bridge to Moorgate-street. In June of t he same year t he southern end of the system was ex­tended from Stockwell to Clapham Common. Now, in t he present week, the northern end has been carried to the Angel at I slington, and opened for traffic, so that there is direct communication from Islington to Clapham Common, connecting

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two hitherto somewhat inaccessible suburbs. The journey is now ma':le in 27 minutes by trains having 2! minutes headway, and it is expected to decrease the time shortly to 24 minutes, and to run trains at two minutes during t he busy hours, morning and evening. Even this short interval might be further reduced were it not for the great crowds to be dealt with at the Mansion House Station. It often takes a minute to fill and empty a train at this station. The total length of t he line is 6! miles, and the speed 14 miles an hour, including 12 stops. There is before Parliament a project, sepa­rately promoted, to carry the line from the '' Angel, " along Pentonville-road and Euston-road to Euston Station; and if that undertaking is carried out, the line will make connection with quite a large number of rail ways, including theN orth-Western at Euston, the Midland at St. Pancras, the Great Northern at IGng's-cross, the Metropolitan at King's-cross, the Great Northern and City (under construction) at Old-street and Moorgate-street., the Metropolitan at Moorgate-street, the Central L ondon at the Bank, the London, Brighton, and South Coast, and the South-Eastern and Chatham at London Bridge, and the South-Eastern and Chatham again at the Ele­phant and at Clapham-road. None of these are physical junctions, but in some cases there are covered ways between the two stations, and in all the distance is insignificant. Not only was the City and South London Rail way the first of its kind, but it has been worked out on independent lines, by British engineers. The early electric equipment was designed by Dr. Ed ward Hopkinson (Messrs. Mather and Platt), and when the extensions out­grew its capacity, the directors, instead of going to A m erica for ideas, adopted the three· wire system of transmitting electric energy, this rail way being, we believe, the first and only example of this system applied to traction. They built a new engine and boiler-house, and installed new machi­nery of the latest type, fitted with all possible labour-saving appliances. This station is situated at Stockwell, and there are sub-stations at London Bridge and at the " Angel. , These sub-stations are fed at 1000 volts above the earth, at 2000 volts across the outers, the additional 500 volts being boosted up on the switchboard at Stockwell, and reduced at the sub-stations by special continuous­current reducers made by the Electric Con­struction Company. At each station there is a battery of 250 Tudor cells to steady the current, and to drive the t rains when the main current is cut off. At the ''Angel " the station is in a tu be 30 ft. in diameter, the lower part of the tube serving as a house for the machinery. New rolling stock is being built for the traffic, including more powerful locomotives and ten trains of four coaches each. In a short time there will be twenty­four trains in operation. All the new hoists are operated by electricity, and have been provided by Messrs. Easton and Co., Limited, of Erith. Mr. P. V. McMahon is the engineer of the railway company ..

THE CoMPLETION oF THE MANCHURIAN RAILWAY.

We have frequently remarked that the engineer is a more powerful personage than the politician, or even the military man. By his works he creates conditions against which these cannot prevail, and hence t he necessity for t he study of what we have called industrial dynamics. The engineer may call forces into action which upset the calculations of all who confine their attent ion to merely local conditions. The developments which have taken place in the methods of communication have shrunken the globe into small dimensions, and brought economic conditions to something like equality. We have had many examples of this during the past quarter of a century, and probably the most recent will be the most im­portant. The congratulations which passed be­t ween the Czar and M. \Vitte on the completion of the Manchurian extension of the great Siberian ra.il­waywere fully justified, not only bythe magnitude of the work which had been done, but also because of the results which were certain to follow. \Vhile we cannot justify all that has been done in the name of Russian diplomacy, we must confess th!\t a great deal of the criticism which has been made of their work in the Far East has been very unfair. A well-known man recently remarked that the Russians had not taken possession of any terri­tory which was of any use to any other Euro­pean Power; and that if he were a Russian, he would rather die than give up the determination

[Nov. 22, 1901.

to have a free opening to the Pacific Coast for their vast territories in the north of Asia. It is only ten years since the Czar, then on a tour round the world, cut the first sod of the railway at Vladivos­tock, and from that time the work has been carried out with an unceasing and tireless energy. The Czar was justified in the warmth of his language to M. Witte, when he said, " I congratulate you on the completion, within so short a time, and amid incredible difficulties, of one of the greatest rail­way undertakings in the world. " We have from time to time given some account of the details of that work ; our object now is not to enter into these, but merely to note the comple­tion of a very important section, which is destined to have great economic, industrial, and political results . .As originally planned, the terminus of the railway was to be at Vladivostock; but, ~ince the qndertaking was entered upon, events in the Far East have added to the scheme. If that scheme had been British instead of Russian, no criticism would have been offered in this country to those developments. The acquisition by Russia, in 1898, of P ort Arthur and Talienwan, with the right to connect these places with the main Siberian system by a railway through Manchuria, not only added to the magnitude of the undertaking, but also to its commercial and industrial import­ance. It is expected when the 1ine is in good work­ing order, and when trains may run uninterruptedly, that the distance between Moscow and Vladivos­tock or Port Arthur will be covered in about ten days at a fare of 12l. for first·class sleeping car. It is also estimated that the journey by the Siberian route from London to Shanghai will take 16 days, and cost 32l., instead of the 35 days and 90l. involved in the present sea route; but probably this calculation is unduly opti­mistic. In any case the commercial results must be very marked. No doubt a great portion of the heavy goods will still be sent by sea ; but much of the lighter goods and a large proportion of the p1ssengers will go overland. The industrial de­velopment of Siberia, however, opens up possi­bilities which it is impossible at the present time even to imagine. Politically, the railway brings Russia right into the politics of the Far East, and places her practically within striking distance of Pekin. We will not, meant ime, attempt to follow the commercial and political results which are certain to follow, but even to superficial observers these must appear to be very great.

THE INTERNATIONAL AssociATION FOR TEsTING TECHNIC..il MATERIALS .AT B UDAPEST.

The International Association for testing tech­nical materials met at Budapest in the week Sep­tember 9 to 14, under the presidency of Professor L. von Tetmajer, who was re-elected president for the next conference, to be held at St. P eters­burg in 1903. The Budapest meeting was attended by 424 deleaates and members, comprising 175 from Hungary, 44 from Austria, 72 from Germany, 38 from France, 27 from Russia, four each from the United I{ingdom and the United States ; all European States, including Turkey, were repre­sented, with t he exception of Greece. Reports from the respective national associations were pre­sented by Professors Ho we, of New York, Le Chatelier, of Paris, and Martens, of Berlin ; and, further, by Professor Rejto on behalf of the Hungarian Organising Committee. The Congress was overburdened with papers, not all of which were in print. Otherwise the arrangements were excellent, and the three days' excursion which followed the five days, meeting, down the Danube to the Beoczin Cement \Vorks, near Peterwardein, the Resicza Iron Works, the Iron Gates, &c., was thoroughly enjoyed by t he 150 particjpants. The Government placed an express tram en­tirely at the disposal of th~ membe~·s for this excursion. The Congress dehberated In two sec­tions dealing respectively with metals and with ston~s, cemAnts, &c. The first, Section A, received many papers, among which we may mention a c.om­prehensi ve report on the Strengths of Matenals, by the President, taken as read ; Baron J uptner's paper on The Carbon Modifications in Iron ; further those by Mesnager (Paris) on Optical Tests; ' Osmond and Cartaud, on Metallo-Micro scopy ; E. Heyn (Charloltenburg), on The Influ­ence of Hydrogen on Iron and of Oxygen on Copper. A. Wahlberg's (Stockholm) paper on Impact T ests after Brinell at Ordinary and Very Low Temperatures, and on Brinell's Sphere

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Nov. 22, I90r.]

T.ests, unfortunately not iu print, was vigorously discussed . Many-notably French memb ers- in­sisted that the habit ual methods of testing did not suffice to characterise materials like mild iron, and that impact tests with indented r ods should be adopted. Oth ers poin ted to t he great difficulties of arriving at m ethods which would secure com­parable results . The Con gress h ence contented itself with expressing a desire for further investi<Ya­tion of the matter, and with recommending s;ch tests. In a paper on The Inter-relation between the Phenon1ena of M echanical, Electrical, and Magnetical Polarisation, Professor von Ho6r (Budapest)~proposed that m echanical tests should, so far as possible, be conducted parallel wit h elec­trical and magnetical tests ; and this motion was carried as a general resolut ion by the Congress. Electricians will welcome this resolution. Dr. Wedding announced t hat the International Sidero­chemical Laboratory would be opened at Ziirich in the Polytechnicum as soon as the gran t of 16,000 francs had been passed. Section B also received many paper s, especially on cements and concretes, and on 'Arn1e:l' Concretes (Concrete Constructions strengthened by Iron). We notice among t he au thors Gary (Charlottenburg) ; Con­sidere, Mercier, Le Chatelier, and Leduc (Paris); B. Blount (London) ; Baire (Amsterdam) ; llel­elubsky (St. P etersburg) ; F oss (CoEenhagen); Feret, Zielinski, Zhuk, and Schaffarzik (Budapest). D efinitions of Portland cements were proposed by E. Schott (Heidelberg) and I{irsch (Vienna). A direct attack was made against the use of blast- furnace slags in Portland cements, and after a long and lively discussion, the following definition was accepted : '' Portland cement is an hydraulic cement, obtained by heating a natural or an artificial mixture of lime and clay, or other materials containing silicates, to sinter­ing ; the product is ground to a fine powder. The Congress does not regard as Portland ce­ments any other hydraulic cements, nor mixtures of Portland cement with other substances. " Herfeldt (Andernach-on-the-Rhine) reported on testing of puzzolane and trass. The St. Petersburg meeting of 1903 will be held by invitation of t he Russian Government. The Association has been in working order since 1896.

HEAVY DIMENSION GRINDI NG .

In a paper read befor e the Manchester Associa­tioi). of Engineers, Mr. Hans Ren olds, who has done so much towards bringing to its present pitch of perfection chain-gearing, described a r ecent de­velopment of dimension grinding in the U nited States. Reamers, milling cutters, and the like have long been finished by means of a grind­ing machine, and, in fact, wibhoub the latter would be valueless from a commercial p oint of view, and hardened surfaces generally have also been quite commonly brought to truth in a similar way. The method has, however, been used com­paratively little .fo~ finishing unh.a~dened wo~k; and as it necessanly Involves an add1t10nal hand}•ng of any piece treated,. it .would s~em at first s1ght that in such cases gnnding has httle to re~ommen~ it. Mr. C. H. Norton, however, an American engi­neer with a large experience in g rinding machinery, thought differently, and when unable to pers uade large firms to take the. mabter up on the sca}e he had in view, determined to open a factory, In which grinding was done for t he trade generally. The machine he has constructed for the purpose will finish off cylindrical work 8ft. long ~y 18 in. in diameter and is of an extremely masstve con­struction. The emery wheels used are 24 in. in diameter. The work operated on is traversed, and n ot the emery wheel, though provision is made for feeding the latter ~owards or f~om t~e work, the actuating screws b eing fit~ed w1th m~crometer heads which render the grindmg of a cy hnder to a predetermined size a very simple matter. Both work and emery wheel. revolye, but. the speed of the former is so adJusted 1n relatiOn to the rate of t raverse that at each r evolution of the work the total' traverse is equal to the width of the wheel. All guidiug surfaces ar e,. of course, very carefully protected from part icles of emery or other dust, and t~e arrange.ment for varying speeds and feeds admtts of practiCally instantaneous changes being . made V.:itl~out the necessit y of stopping the machine. ThlB IS accom­plished by joining the different steps of t~e b elt pulley by conical surfaces, up or down whiCh .the belt can be forced frorr.. one step to another w1th-

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E N G I N E E R I N G. out stopping the m achine. Mr. Norton states that i t is a bad plan to put the machine in charge of a good turner, as t he latter is misled by his lathe experience, and therefore fails to get the same out­put from the machine as an inexperienced but intel­ligent labourer. Thus in using t he steady-rests the latter does not trouble to " spot off" bearing places for them on the rough-turned bar ; but simply lets them r est on t he rough-t urned surface and goes ahead. The use of these steady-rests is found advisable even on the h eaviest work. Thus Mr. Norton states t hat wit hout the steady-rests, a locomotive piston-rod, 3! in. in diameter an d 50 in. long, and rough turned iz in. over size, will r equire two hours to finish ; whilst by using steady-rests th e work will be finish ed with equal accuracy in t hirty minutes. Mr. Norton's firm are now doing a very large business in finishing with t heir machines work from outside factories . This comes to them rough-turned from ·:?<r in. to trJ in . over size, and is then finished in the grind­ing machine to size within the 1 -if"1n5 of an inch in much less t ime than would be needed for fi nish­ing on the lathe, and the work turnod ou t is, moreover, more truly cylindrical, and has a sur­face which requires n either file nor emery cloth to r ender it smooth. As an instance of the time saved, Mr. H ans R enolds showed at the meeting two bars 14 in. long and originally 2~ in . in diameter. The one was rough t urned to 21 in. in diameter, and the other, after roughing in a similar way, was finished to 2fa- in. in diameter by grinding, t he time taken being 12 minutes. T o finish t he bar entirely in the lathe would have r equired, by turning and filin g, seven or eight times as much t ime. Mr. Renolds ment ions that Oorliss valves 8 in. in diameter and 48 in. long are sent to t he N orton factory for finishing from engine - builders as much as 1000 m iles away.

NOTES FROM THE UNITED STATES. PHILADEL"PHIA, November 14.

THE activity in iron and steel has been a. surprise to manufacturers, consumers, jobbers, and others, and the inquiries of t he past forty-eight hours indicate the strong probability of a heavier demand than has yet been experienced for early deliveries. While prices have not yet advanced, and while it is safe to say that advances are improbable, there are enough who think otherwise to give the market an unsettled condit ion and to lead to higher prices for specia l accommodation. The event of the past few days has been the attempted organisation of a 50,000,000 dols. trust made up of nearly all the independent plate mills outside of the great J ones and Laughlins plant at Pittsburgh. This combination will work in harmony with the United States Steel Corporation, if it goes through, as it appears to be on the point of doing. The com­bining tendency is at work in other directions, and we may expect the so - called independent producing interests to very largely come under t he control of t he great central power. The volume of business for the past week has been exceptionally large, and it is quite prob3oble that demand will con­tinue about as it has been, and that large consumers will make purchases for summer delivery. The great feature of the past few days has been the scarcity of cars which amounts to a famin e. T h( re are not enough cars' to haul finished products, coke or coal, wheat or lumber, and many other heavy articles of mercha?dise. The condition was never so intrnse and aggravatmg as it is, and the pressu~e for r?lling stock is ~ikely. t? co~­tinue for an indefintte penod. Steel rail a.cttVIty IS as great as o~hers, and the estimat~d volume of busi­ness includmg unfilled orders, 1s now placed at 1 300 000 t ons. Railroad requirements are far from b~ing' filled. Numerous heavy requirements are being heard of. All lines of hardware manufacture are crowded. Great activity continues in engineering and mechanical branches. Electrical equipment p1ants ar.e bringing in new capacity. Conditions are most grati­fying. Coal and coke are in abundant supply at their sources but distribution is much hampered. A heavy demand continues for all lines of pig iron. Steel billet production is still over-t axed. Bar iron and steel are held high, and are very active.

GYROSOOPIO ACTION AND THE LOSS OF THE " 00 BRA."

To THE EDITOR oF ENGINEERING. Sxn,-In reply to Mr. Henry J. Da.vis, I _have to say

that a perfect gyroscope of the typ~ sketched m m~ lette.r, without friction either in the bearmgs of the aX:ts or m the pivot about whic~ ib prec~ses, and suppo3IDg that the air opposes n? resista.nc~, wlll nob ~esc~nd a.~ all by the action of gravity, but will preoeas w1bh tts axiS ab b~e same inclination to the vertical for ever an? ever. . I eatd in my letter that the axis would precess m a horizontal

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plcvne because I supposed it to be placed horizontally to begin' with; but i f placed at any inclination, it will preserve that inclination for ever, if undisturbed. If a ahght tap be given to the frame, the axis will wag ~bout its previous inclination, and describe a waved cone m apace, as Mr Maofarlane Gray says of the top, at about the mi?dl~ of the firsb column on page 624, " the top keeps on sp10mng but wavering continually to one aide and the other .of the position of inclined balance." I am sure that so ~mshed a mecha.ni01an as Mr. Gray does nob mean that th1s waver­ing is a necessary conditio~; he is only taking a. gen.eral case. The simplest case 1s one of smooth motion m a true or E uclidean cone.

But Mr. Da.vis will eay-In a practical trial I find that the axis does gradually fall ; and any one over six years of age will tell you that a top does not remain inclined, but gets upright again when whipped over to a sloping position. Tliat is because another couple is acting, and the axis turns so as to get a com ponen b rotation of toe sort that that couple bends to produce. Your correspondent " K. Y." states the direction of change correctly: the couple demands, so to speak, rotation about a certain direction, the axis satisfies that couple by burnin~ so that its rotation acquires a component about that dueotion ; and the rate of acqui3ition of that component is strictly proportional to the rnagnitude of the cowple. The couple keeps its accounts correctly; ib is never out in its cash.

What then are the couples which make the gyroscope fall in the one case, and the top, which is only another gyroscope, rise in the other ?

First, take Mr. Davis's case of the gyroscope. Instead of a fine point, leb the top of the vertical support be a spherical knob of considerable size, so as to produce a ~ood deal of friction. The axis will descend much qu1cker than when the sharp point was employed. This friction-opposing motion about a vertical axis lS a couple aboub a vertical axis, in a sense contrary to the precession. Let Mr. Da.vis draw a circle about the ,Pivot in my Fig. 2 (page 625 ante), and put an arrow on 1t contrary to the arrow a, to represent the friction couple, and let him con-

(7118)

-----·--... .#··--- -.... __ ... ) ~ .... _ _ ,.~ '\ ------------

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sider which way the axis must move to get a componen~ rotation of the sort that this couple deals in. Clearly the top must fall. However sharp the _point of support, it must have some friction, and there IS also the resistance of the air; but there is yet another couple, a little more obscure, which opposes the preceesion and eo helps the system to fall; and I will endeavour to describe it. It is due, strange as it may appear to those who hear it for the first time, to the frict10n of the bearings of the axis of the top, and the friction of the air opposing motion about the axis. These causes diminish the rate of rota­tion about the axie, and consequently (as follows from bhe formula) the rate of precession increases ; but accele­rating the precession involves an opposite reaction due to the inertia of the body, opposing the precession like the friction of the pivot, and so the t?P _falls. T~erefore, if a gyrosco-pe had an absolutely fr1ct1onless ptvob, but had friction in the bearings of the top, ib would gradually fall.

Indeed- (how hard ibis to tell a11 the truth at once I)­my statement in your issue of November 1, that the appa­ratus does not fall down when placed on the support, requires modification : if the liand releases the ring "cl~n, " without impul~e t~ the right or left, in pl~c­ing Ib on the support, Ib wtll fall through a small dts­tance, because the system has to be accelerated to the speed of precession froiD: rest, and ~ts inertia <?PPOSES a reaction contrary to tb1s acceleratiOn. But 1£ ab the ruomenb the band lets go of the frame, the latter has the speed of precession w, then on release it will nob fall, but continue to move in a. plane if horizontal, and in a none if sloping .

Now, as to the small boy's gyroscope, or peg-top, which generally rises to the vertical position. It depends on the shape of the point on which it spins whether ib 1tJiU so rise. If it be ground to a clean conical point like a centre punch, and this point turns in a small depression or centre-punch dab in the t able, the top will nob rise, but will precess in a cone, just as in the case of the gyroscope above considered, gradually falling and precessing quicker as the spin dies out. But if the point is rounded, as is usual, then in any inclined position the top is not resting on the poinb of the peg, hub on one point of a smaU circular section of diameter a in the annexed figure, a little above the point. Now if there were absolutely no friction between the peg and the table, the top would precess in a double cone about its centre of gravity, as shown by the two dotted lines ; and since there is friction, the small circle a constitutes a little locomotive driving wheel urging the precessional motion round faster than its n~tural rate. This constitutes a couple about a vertical axis in the same direction as the precession. After what I have said above as to the direction of precession, it should be clear to everyone who reads this carefully that the preces~ion is in the eame direction ae

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the rotation as viewed from above ; therefore the effect o! the friction couple is to increase the component rota­tlOn of the top about a. vertical axis ; in other words, to make it more upright.

I would recommend all who wish bo master this subject to get a. most charming little book by Professor John Perry, called "The Spinning Top," published by the Society for the Promo~ion of Christ1a.n Knowledge; price, I think, half-a-crown. Also "The Mechanics of Rota­tion," or some such name, by Worthington ; the publisher ~ have forgott~n; the price is pro~ably a. little mor~. Ib 1s no use abusmg the gyroscope, hke "K. Y.'s " fnends. What does Kipling's old sergeant say? I quote from memory:

" If the 'alf of your bullets fly wide in the ditch, Don'b call your Martini a. cross-eyed old bitch; She's human, as you are-you treat her as sich, And she'll fight for the young British soldier."

If "K. Y." will treat the instrument "as sich," he will soon understand it . He has half the truth- namely, as to which way the axis is deflected ; the other half-the rate of deflection-is almost as simple, viz., the sort of r.:>tation which the acting couple tends to produce, and produces, when applied to a body at rest, is produced, 0/I'IAl at pre· cisely the same 'rate, when the couple is applied to a. body which is already rotating in anobher manner ; only the gain of the sort of motion the couple requires is brought about by the deflection of the ortginal axis of rotation towards a direction coincident with, or parallel to, the axis of the applied couple.

The following is a good 'recipe for teaching the prin­ciples. Take one man who understands the matter, and not more than three or four who do nob, but really want to. Let them all be good enough friends to wrangle hobly and contradict each other without losing their tempers, and set them to fighb for two or three hours with one or more gyroscopes on the table before them. The instruments need not be expensive ones: the form shown in my last letter costs aoout 6d. : there wa.s a very pretty_ one at the last Brussels Exposition, having a. miniature Eiffel Tower for a. supporfl, and a cardboard box which precessed ou one corner when the top in motion wa.s shut up inside it (price 1 franc). The instru­men b has not escaped the notice of those extremely clever people, the makers of the toys which a.re sold on the kerbston(>. I bought an admirable one of a new type for 2d. from a.n itinerant merchant in the Strand, in which the couple and consequent precession could be re­ver.aed in a. moment. Also much can be done with bicycle wheels, as several correspondents have shown. Well, the first sitting will make those learners think they know a.ll about it; but they will be back the next da.y and assail their instructor with, " What you say is a.ll very well, my dear fellow, but you are quite wrong. How do you account for this ?'' And they will proceed to disclose each a. differeab mare's nest. With very little help from the man who knowE', they will annihilate each other's mis­takes, a.nd will soon become confirmed gyrosta.ticia.n~.

Mr. Ca.ssel need not suppose one set of propellers to be oub of the water, a.nd racmg, to upset Sir H. Maxim's equation 0 :::: 0; a.ll he ba.s to suppose is the order from the deck to the engine-room which must sometimes be given, " port engines full speed ahead, starboard engines full speed astern," and be ba.s a.ll the turbines going the same way, and the sum, instead of the difference, of their gyrosta.tic efforts acting on the ship. It will nob do her the slightest ba.rm. I wish to write with all proper restraint of a. gentleman so obviously earnest in his desire to arrive at the truth as Mr. Ca.ssel, and imbued with so evidently patriotic a. feeling, so I will j usb ask him to reconsider his statement that two parts of a. rigid body ma.y be moving with different angular velocities. The idea is entirely inadmissible. And a.s to the combined pitching, rolling, a.nd steering motion, it sounds very formidable; but the forces due to each a.re those which would exist if it alone existed. Thufl, let a be the angle of the shaft with . the horizontal ab any moment, we have a. horizontal rotation In cos a, and a. vertical rotation In sin a; and if-

X be the angular rate of pitching ; 1{1 , , , rolling; w , , , steering ;

the couples called out arc-for pitching, In X ; , , rolling, In 1{1 sio a ; , steering, In w cos a..

I is, o£ course, the moment of inert' a w k'l a.nd n the u , rate of rotation of the shafb.

Mr. H. J. Bi.ngham Powell's vie~s are ~orrecb, unless his closing sentence means that he thmks, w1th Mr. CasseJ, that two parts of a. rigid body can have different instan­taneous angular velocities. Mr. ~illiam Leig~ton J orda.n'd case is almost hopeless ; he thmks gyrostat10 effec'lis are produced by the motion of revolving shafts parallel to themselves ; and this is curious, as be lias a gyroscope. I should think he could easily satisfy himself that such is not the ca.se, but that the moment he changes the d,irec­tion of the revolving shaft the effects show themselv~. If the shaft of a ~hip is. horizontal, a.nd s~e rolls ever so inuch keeping 1t honzonta.l, there wlll be nob the sli~htest gyrostabic effec~; and this effect, ~her~ it does enst, is not due to gra.vtty, as ~r. J ~rda.n tma.gmes, but to inertia; gravity mere~y supphes-m s01;ne oases, hub nob in all-the couple. wbto~ ca.':lses precessiOn. We can conceive a. universe m whwh t~ertlla.. was poesess~d by bodies, but nob mutual attraot10n; tn such a. uruverse gyrostatic effects would be the same as they are now.

All this is dreadfully ~on g. I ~ear there i~ su~h a thing a.a 'lJisinertice scribendi, wh10h requues defleotmg mto.another direction· but I would say just one more word 1n reply to Mr. D~vis. He says "gyroscopic action is only caused

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E N C I N E E R I N G. [Nov. 22, 1901.

by a change in the direction of the axis of revolution." It is nob quite that ; say, rather, "the gyrostatic couple is i nsepara.ble from the change of direction." The couple may cause the precession, as in the free gyrostat, or the forced change of direction ma.y call into existence the couple.

the opposite direction with the reversal of the stresses. It must, however, I think, be also admitted that by getting half over any heavy spar (such as the mast of a large ship) chancing to be in the vessel's course, a similar stress a.nd resulting fracture might be caused ; and I see no sufficient reason to be sure that so great a stress could be created by any gyroscopic action of the propellers and turbines a.s could be created by such a spar.

Your obedient servant,

15, Rue Ba.sseina.ya., Kieff, October 31-November 13, 1901.

G. A. MATI'HEY.

To THE EDITOR OF ENGINEERING. SIR,- ! beg that you will allow me to record a. protest

a.~ainst the manner m which your correspondent "Expe­rtentia Docet" denounces as either ignorant or dishonest all who differ from his opinion on the above subject. He seem~ to consider the fact of two of your correspondents, each properly held in high repute in the scientific world, having argued aga.insb the existence of any gyroscopic actiop on board the Cobra. ought to be sufficient to put a.n end t~ further discussion. But against tha.b view I beg you to bear in mind that one of his two champions (Mr. Macfarlane Gray) has declared the gyroscope to be a. ''mystery " ; a.nd the other (Sir Hira.m Maxim) in his letter in your igsue of October 25 say~, "there is no philosophical instrument in existence which is so little understood," and the expression of such opinions by men so well known to be of great experience and ability in scientific matters must, I think, be considered fully to justi.fy your apparent desire to have the matter threshed out m your columns.

Presuming that you continue disposed to keep your columns open for the discussion, I offdr further comments on two points.

First, Sir Hira.m Maxim alludes to the tendency of the rotation of a rifle bullet to roll on the air compressed bel_ow it as tending to cause the bullet with a right-hand twiSt to be deflected to the right, recognising, however, that the actual deflection is in the opposite direction. In connection with that theory of the rolling of a. projectile, a paper by L ord R9.yleigh (Scientific Papers. vol. I, page 344) '' Oa the irregular flight of a. tennis ball," is, I think, appropriate to the present discussion, as ib gives a. practical refuba.oion of a similar theory ad va.nced in explanation of the motion of a tennis ball progressing with a. horizontal twist. In the case of the tennis ball, a.s well as in that of the bullet, the actual deviation from the straight course is in the opposite direction to that which the suggested rolling motion would tend to cause. That practical divergence from the theory has been pointed out by Lord Rl-yleigh in the one case, a.nd by Sir Hiram Maxim in the other. The deviation of the bullet agrees with the combined action of gravity a.nd the rotating motion described in connection with bhe dia­gram in my letter which you published on the 1st inst., and in the case of the tennis b9.ll, moving with a. hori­zontal twist (instead of the vertical twist of the bullet) the conflicting action is between the motions of progression a.nd rotation. In both cases the resulting deflection accords with the gyroscopic reaction described in my letters in your issues of the 1st and 8th inst.

The same gyroscopic reaction as described in those three cases is created by the flapping of the· wings of a bird, a.s the reaction against the downward stroke of the wings acts reciprocally in the two wings, making the resistance to the downward stroke of each wing act as a. fulcrum to the leverage exerted by the resistance to the downward stroke of the other win6'· I venture to recommend your correspondent, "Exper1entia. D oceb," to endeavour to test the above with his double gyroscope, and I also tell him beforehand the result will be that immediately he gets the correct con­flicting action between gravity a.nd the two opposite motions of rotation, the flimsy gyroscopes be alludes to will for a.n instant disappear in a buzzing blur, and the nexb instant they will reappear in silent frag­ments on the floor. In those gyroscopes the ring which holds the pivots for the rotating axis of the disc is suffi­ciently pliant to be easily elongated by the vibrations in the line of the axis, so as to allow the disc to escape from the pivots; but the sinews of the bird's wing~ hold their joints together, a.nd use the corresponding reactions a.ga.insb their motion as fulcra for lifting the bird.

Secondly, it seems to be taken for granted by some of your correspondents that because the gyroscopes rotating m juxta-position in opposite directions allow their axes to be easily moved in a manner which would be resisted by either of them alone, therefore there ca.n be no gyrosco.J?iC stress in a ship in which two turbines rotabe in opposite directions. The fact, however, is that the force of each stress must of necessity continue to be exactly the same a.s when either gyroscope is alone, though the combined stress cannot ba.ve effectrive action in either of the direc­tions in which the gyroscopes a.ct singly. A pair of scales is easily tilted by a slight force, whether empty or heavily loaded with equn.l weights in each scale; though if weighed fully down by a. weight in one scale only, the beam might resist the effort of the lesser force to change its position; but there is, nevertheless, a. greater str~s on the beam when both scales a.re heavily loaded. The length of the ship ma.y be considered to represent the beam of the pair of scales ; a. gyroscopic stroos of the turbines and propellers, the weight in one scale (which may act either upwards or downwards) · a.nd the action of the sea on the bow of the vessel, the weight in the opposite scale (which may be either a.n upward thrust of the sea., or the downward pr~sure of a heavy sea. shipped over the bow). The bending inwards of the Cobra's plates where the transverse fracture across the bottom of the vessel occurred, agt·ees with the idea. of the bottom of the vessel having first given wa.y by crushing inwards under the latter of the above-mentioned stresses, and then, when weakened by that fracture, ha.ving doubled up in

I am, Sir, your obedient servant,

November 18, 1901. WM. LEIGHTON JoRDAN.

PATENTS IN SOUTH AFRICA. To THE EDITOR OF ENGINEERING.

~~~-We a.re 'Ya.iting for and hoping for a United Bnttsh South Afnca.. I hear rumours of alterations in the patent laws of the new colonies in South Africa, a.nd your readers interested in such matters should be on their guard. . My immediate reason for writing is to suggest that the mterested Governments should be urged to arran~e that "one South African J?~tenb " should cover a.ll British South African possess10ns; it would be still better to adopt the French system, and make one British patent cover all British possessions, or, to meet the prejudice of some, make two distinct sets of patents-one for Greab Britain and Ireland, a.nd one for all other British Posses­sions; call the latter the "Imperial patent."

The present arrangements here oblige us to take out ~ve or six separate patents : a. very heavy tax on mventors.

The country is extensive; but the centres, where the patents are likely to be of use, a.re few and far a.pa.rb, and the population small in any of them, compared to Euro­pean towns. The adjustment of revenue could easily be arranged between the various Governments. Patenb laws were made to encourage invention, and for the benefit of the public generally; the multiplication of expenses pre­vents many inventors from coming forward, and progress is consequently delayed.

Some years back a British patent was sound here; bnt we have gone backwarde!, and have wiped oub that sensible law.

Yours faithfully, A. W. AoKERMANN, A.M. Inst. C.E.

Castle Compal!y'B Buildings, Adderley·street, Cape Town, October 22, 1901.

THE SuEz CaN AL.-The transit revenue of the Suez Cana Company in the tirsb 10 months of this year amounted to 3,345,994t., as compared with 2,981,35ll. in the corre­sponding period of 1900, and 3, 099, 767l. in the corre­sponding period of 1899. The company will pay on J a.nuary 1, an interim dividend of 2l. 2~. per ordma.ry share for 1901. This dividend shows a.n increase of 43. per share a.s compared with the corresponding distribution made on J a.nua.ry 1, 1901.

T HE GERMAN IRON TRADE.-The exports of metal­lurgical products of all kinds from the Zoll verein in the first nine months of this year amounted to 1,599,477 tons, as compared with 1,124,416 tons in the corresponding period of 1900; 1,152,833 tons in the corresponding period of 1899; 1,231,998 tons in the corresponding period of 1898; a.nd 1,009,115 tons in the corresponding period of 1897. The imports of metallurg ical products of all kinds into the ZoJl verein in the first nine months of this year amounted tO 329,765 tone, as compared with 775,807 tons in the corresponding period of 1900; 605,858 tons in the corresponding period of 1899 ; 372,929 tons in the corresponding period of 1898; and 404,540 tons in the corresponding period of 1897. The exports ac­cordingly exceeded the imports in the first nine months of this year by 1,269, 712 tons. The corresponding excess of exports over imports in the corresponding l?eriod of 1900 was 348,609 tons ; in the corresponding per1od of 1899, 546,975 tons ; in the corresponding period of 1898, 869,064 tons ; a.nd in the corresponding period of 1897, 604,575 tons. It will be seen that the exportation excess has varied considerably year by year, a.nd that after falling to a. comparatively low point in the first three quarters of 1900, it experienced a. rapid a.1vance in the tirst three quarters of this year. The value of the metallurgical products of a.ll kinds exported from Germany in the first nine months of this year was 21, 741,500l., as compared with 17,961,000l. in the corresponding period of 1900 ; 16,059,5001. in the corresponding period of 1899 ; 13,643,500l. in the corresponding period of 1898; a.nd 12,294,500l. in the corresponding period of 1897. The value of the imports in the first nine months of this year was 3t147,500l., as compared with 5,439,500l. in the corre­sponding period of 1900; 3,927,000l. in the corresponding period of 1899; 2,667,000l. in the corresponding period of 1898, a.nd 2, 547,000l. in the corresponding pe~od of 1897. The excess value of the exports m the first mne months of this year was accordingly 18, 594,000l., as compared with 12,521,500l. in the corresponding period of HlOO; 12,132,500l. in the corresponding period of :1899 ; 10,976,500l. in the corresponding period of 1898; and 9 747,500l. in the corresponding period of 1897. Rails were e~ported from Germany in the first nine months of this year to the extent of 125,538 tons, as compared with 111,200 tons in the corresponding period of 1900 ; bars, to the extent of 225,748 tons, as compared with 124,114 tons ; plates, to the extenb of 180,147 tons, as compared with 115,165 tons; wire, to the extent of 113,966 tons, as com­pared with 69,028 tons; galvanised wire, to the extent of 64,245 ton~, a.s compared with 57,747 tons; axles and tyres, to the extent of 37,349 tons, as compared wibh 35 609 tons; pipes, to the extent of 34,418 tons, a.s com· p~red with 29,711 tons ; and fish-plates, to the extent of 22,526 ton~, as compared with 26,677 tone.

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Nov. 12, I 90 I. J INDUSTRIAL NOTES.

THE state of the labour market, as disclosed in the Board of Trade returns, Labour Department remains unchanged in comparison with the month 'previous but is not so good as in the same month a year ago. Th~ ~eturns upon wh~ch these conclusions are based are 2390 m number, of wh10h 1727 were recei ,•ed from employers 5,62 from tr~de unions, and 101 from other sources: 'Ihe curve hoe as to employment, or, rather, non-em­ployment, has for two months been practically un­changed, but steady. In the 142 unions specially reported upon there was an aggregate of 544,827 mem­bers, of whom 19,995, or 3.7per cent., were reported as unemployed,. the same as in the previous month, as compared. w1th 3.3 per cent. in the same month a year ago, m four fewer unions, with a. total of 535,668 members, a comparison which is favourable.

. As r~gards employment in the several groups of mdustrt~s, ther~ ~as a. decre8.se in the average time wo~ked m co~lmtnmg, as compared with a year ago, but a~ mcrea.se m. the number employed. As compared wtth t~e preVI·OUs month, there was practically no change .m the volume of employment. At collieries employmg 483,117 persons, the pits worked on an average 5.36 days per week in the four weeks as com­pared with the same average in the previou~ month and 5.63 days a year ago. '

In . ironstone. mining employment continues good, showmg pract1cally no change. There was a slight d~crease in the average tim? worked as compared w1th a year ago, and a. considerable decrease in the numbe~ employed. At 137 mines and open works. employmg 15,418 persons, the time worked was 5.76 days per week ; in the previous month 5. 76 days a year ago 5. 78 days. This is fairly regular. '

Employment in the pig-iron industry shows a slight decline, and is considerably worse than a year ago. At the works of 113 ironmasters furnishing returns 315 furnaces were in blast, employing about 21,900 persons, as Clmpared with 321 furn aces in the previous month, and 344 a year ago.

In the manufacture of iron and steel employment shows a further improvement as compared with a month ago, and is now better than it was a year ago. At 202 works, covered by the returns, 81,418 persons were employed ; the totll volume of employ­ment·, taking into account both the number employed and the number of shifts worked, shows an increase of 2.5 per cent. as compared with the previous month, and of 3.5 per cent. a.s compared with the same month a. year ago.

The tinplate industry also shows a further im­provement, and is better than a year ago. There were 381 mills at work, including those engaged in the manufacture of blackplates, as compared with 377 at the end of the previous month and 360 a year ago. The number employed was about 19,000 persons.

In several branche3 of the engineering and metal trades group there is a complaint of a slight falling off in employment. The proportion of unemployed mem· hers of unions wa.s 3. 7 per cent., as compared with 3.5 per cent. in t he previous month, and 2. 9 per cent. a year ago. The depression in the textile machine industry will account for much of this.

In the shipbuilding industries some decline in em­ployment is visible. The proportion of unemployed members was 4.2 per cent., as compared with 3.9 per cent. in the month previous, and 2. 6 per cent. a year a.go. But the report of the union shows that there is still work for many of the idle hands to do.

Employment in the building trades has continued to decline in most branches. The proportion of unemployed members of trade unions reporting was 3.1 per cent., as compared with 2. 9 per cent. in the month previous; but in the same month of last year it was 2.5 per cent. In the furnishing and woodworking trades it is not quite so good. The proportion of unemployed union members was 3. 6 per cent., as compared with 3. 2 per cent. in the previous month, and 3. 7 per cent. in the same month a year ago.

Most branches of the printing and bookbinding trades show a further improvement, as is usual at this season. The proportion of unemployed union members was 4.6 per cent., as compared with 5.6 per cent. in the month previous, and 4.5 per cent. in the same month of last year. In the paper trades there is little change. The proportion of unemployed union members was 2.3 per cent; in the previous month, 2.2 per cent.; a. year a.go, 2.2 per c-ent.

Employment in the boot and shoe trades is reported to be slack in most centres. In the other leather trades it has continued to decline. The proportion of unemployed union members was 3. 2 per cent.; in the previous month, 3 per cent.; same month a year ago, 2. 2 per oen t.

In the glass trades there is a. slight decline ; employ• ment is not so good as a month ago, or as a year ago.

In the cotton trades the spinning bra.noh eontinues

E N G I N E E R I N G. fair; in the weaving branch there is some improve· ment, but it is moderate only. A considerable per­centage is unemployed.

The proportion of females in full employment, in factories ~epor.tin~, employing about 80,000, was 84 per cent. 1_!1 spmnmg mtlls, and 71 per cent. in weav­mg factor1es, as compared with 88 and 69 per cent. respectively in the previous month, and 64 and 52 per cent. respectively in same month a year ago.

Employment in the woollen trade is fairly good ; in the. worsted trade there is some improvement; in t he hos1ery branches there is a little improvement.

Agricultural labour is well employed on the whole, but ca~ual men .are. in irregular work.. The supply of labour m most d1str1cts reported upon 1s quite equal to the demand.

Dock and riverside labour is fairly employed in the Lo?don docks and wharves. The average number datly employed was 16,845 ; in the previous four weeks 16,335 ; a year ago, 17,711.

. The~e were 26 fresh labour disputes in the month, ~volvmg 10,501 persons-5488 directly, and 5013 in­dtrectly. In the previous month there were 33 dis­putes, involving 8654 persons; in the same month of last yel.r 30. disputes, involving 16,079 workpeople. Of the 26 dtsputes in the month, 10 were in mining an? ~ uarryiog ; e~gh.t in the engineering and ship· butldmg groups ; s1x tn the textile trades ; and two in other trades. Thirty disputes, old and new, were settled. Four, involviug 1304 persons, in favour of the workpeople ; 16, involving 3244, in favour of the em­ployers ; and 10, involving 2668, were compromised.

Changes in the rates of wages affected 17,684 persons. The net effect was a gain in wages of f d. weekly per head. In the preceding month the net result wa<3 a reduction of 9!d. per head in the weekly wages of 1.72,890 workpe~ple. In the same month of last year tnere was a. gam of ls. 11d. per head in the weekly wages of 142,776 work people. The chief advance was in the wages of co.},lminera in the Forest of De1n ; the decrease was in the wages of ironstone miners in Cleve­land. Only 35 workpeople were reported to be on strike in all those changes in wages.

The J ournal of tlte A. malgamated Society of Engi· neet·s reports that the membership increased from 90,247 to 90,686 during the month. "The number of members on donation benefit continues to show an ominous increase, having reached 2723, an increase of 214 in the month, which is the highest point reached for some years. " The number on superannuation benefit increased by 90, and has now reached 3989; the number on ~ick benefit was 1957, also an increase. A conference with the employers has resulted in an advance of wages, under contractors, at Portsmouth and Devonport from 37s. 6d. to 38s. per week, to cor­respond with the rates a.t other dockyard centres. The question of out-workers' insurance was discussed, but the conference was adjourned. The report states, however, that the deliberations were of a friendly character. In the matter of levies, the vote of 3d. for the benevolent fund was carried by 10,071 for to 12 against; for the trade fund 3d., by 9156 for to 141 against. The two levies were therefore carried. The following notice is significant : " There has been considerable trouble c~used by members leaving t heir work without previous sanction of council. Council therefore, here intimate that such should not continue, on pain of forfeiture of benefits.'' Strikes without sanction are usually di~astrous to all concerned. "The elimination of the unfib " is progressing, "some more of the malingering gentry " being got rid of during the month. One, whose name is given, "has been excluded for chronic laziness. He had received no less than 213l. 2s. 8d. in sick and donation benefit, and ought to have been excluded long ago. '' Others are named.

The monthly report of the Boilermakers and Iron Shipbuilders says, as regards the state of trade : '' From Cardiff, London, Liverpool, and Hull come the tale of want of work ; and although that is an un­doubted truth, yet the fact remains that for many of those out of work employment can be found else­where." In "twelve other district s work is in a flourishing condition, with the likelihood of its con­tinuance for at least a few months more." The total number of members on the funds, out of a total of 48,105, was 4368- increase of 515 in the month. The total employed was 2128, laE?t month 1738. Of that totall662 were on home donation, as compared with 1327 last month. On the sick list there were 1522, and on superannuation 718; the increase was under every head. Attention is called to t he fact that while so many a.re unemployed, advertisements appear in the reports of situatiOns open, which have uot yet been filled. There was an increase of 760l. on home donation last quarter, and yet, the report states, it was a. record one in the shipbuilding industry. The expenditure was 638ll. in the month, at the rate of 1595l. 5s. per week; an increase of 123l. 10s. 3d. per week. This is a large rate of increase at a time when

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trade, on the whole, is very favourable. Another vote is being taken as regards apprentice agreements in shipyards. The reason assigned is the small vote recorded on the last occasion; over fifty branches never voted at all. The points to be voted upon are : Limitation of age, indentures, increased pay to ap­prentices, right of limiting the number, and publica­tion of full list annually. Members are urged to vote in order to maintain the position of the society. Two disputes as to demarcation of work were settled during the month by arbitration. The Board of Trade arbitrator gave the award in favour of the union in both cases at Bristol and at Goole.

In the Wolverhampton district the iron trades are reported to be quiet; in some finished branches q uota.tions are weaker. Consumers continue to limit orders for the most part to immediate requirements. Marked bars and best chain and cable iron are, how­e,~er, in steady demand, a.nd these maintain full rates. In unmarked qualities makers are not able to com­mand the recent advance rates owing to Belgium bars sent into the market at lower rates. With lessened inquiry, sheets have been sold at lower rates of from Is. to 2s. per ton. Hoops and tube strip are in fair demand. Steel is in active demand, and quarter-day rates are fully maintained ; but foreign agents are securing good ot·ders at lower rates. Pig iron is in strong demand, is scarce, and makers command their own terms. The engineering and allied trades are in full employment generally. Moulders report a. decline; cycle and motor makers as dull. At Madeley and Ooalbrookdale employment is slack, and also with the malleable ironworkers at Walsa.ll. In t he hardware industries employment generally is good, or fairly good. In some branches the report is that trade is moderate; in two branches quiet; in two branches slack. On the whole, the position is favourable, and the outlook is not to any degree discouraging.

In the Birmingham district the iron trade has been quiet- business restricted to immediate '« ants. It is reported that neither smelters nor makers will increase their output at present rates. Competition in colonial and foreign markets is said to be severe. Home demand is well maintained for railway work, con­structive engineering, shipbuilding, and for railway wagons ; the latter branch has been busy all the year in local yards. Marked bars are in good request; Other kinds and qualities no change. Pig iron scarce ; increased output expected. The engineering and allied trades good to moderate. In the cycle and motor industries quiet. Electrical workers fully employed.

The complaint throughout Lancashire is that there is a continued slackening off in some of the principal branches of engineering, and that it is making itself appreciably felt in the augmented number of unem­ployed union members in those trades. It is reported that the falling·off in orders among the toolma.kera is particularly noticeable, and there is less new work been given out in boiler-making, and in the more general branches. lVIeanwhile, the textile machine­making industry is very depressed, with no material signs of increasing activity. Most branches of elec· trical engineering are still exceedingly busy, but it is said that t he pressure is not quite so gre~t as it was. Locomotive and railway-warson builders are full of ·work for a considerable time ahead, and a fair weight of new orders is still coming forward in railway work. The iron market continues quiet, though the full attendance last week rather indicated renewed interest in business traneactions. Pig-iron buying is said to be restricted to requirements ; although mer­chants offered, it is said, under current rates, yet con­sumers were not tempted. In the finished branches business comes forward in moderate weight. A fair business is reported in the steel trade, but only for present requirements, and prices have been rather weak. Generally, the position and prospects are not regarded as bright.

Trade unionists are rather alarmed at the division in Dewsbury, and the candidature of practically two labour candidates. It is a case of Trade Unionism re1·sus Socialism. The Trades Council have selected a candi­date, while & Social Democratic candidate is being forced upon the constituency by another section, backed by outsiders. The two sections are by no means agreed as to a. labour policy.

The Sliding Scale Joint Committee of the South Wales and .N!onmouthshire Miners met last week to oonsider the situation. The operatives' section and the employers' section met separately at first, then jointly. Nfr . W. Brace, for· the miners, said that the stop-days were for the advantage of the coalowners as much a.a the miners ; they were to arrest the downward trend of prices. It was reported that the coalowners refused to discuss the policy, in view of legal proceedings. It was further stated that instead of a number of separate actions, the whole question will be raised by a con­solidation of actions as a test case. Power to do this

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E N G I N E E R I N G. [Nov. 22, 19Ct.

THE BARROW HEJYIATITE STEEL WORKS.

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is given by t he Act, and rules and orders of the Court provide for such consolidation. In the case at issue some very broad questions may arise as to public interest, as well as regards the personal rights of in­dividuals or of bodies of men associated together for trade purposes.

The Northumberland Miners assembled at their half-yearly meeting on Saturday last, and again de­cided not to join the National Federat ion of Miners by 58 to 8 votes. This seems conclusive. But the Federation officials seem to think that the men will come over in parcels, in Ppite of the votes of t heir duly-elected delegates.

It is reported that the Judges have decided that the action of the Ta.ff Vale Railway Com­pany against the Amalgamated Society of R!i.ilway Servants shall be tried in London, and not at the Glamorganshire Assizes, a-s was desired by the de­fendante. It is stated that the company's statement of claim is not yet delivered. How long these actions at law take. Surely this is a matter which in

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the public interMt ought to be settled one way or another without delay.

It appears that the great strike of French miners is to take place after all. Indeed, over 2000 are reported to be out on strike already. A conference was held towards the close of last week between some French and English representatives. Mr. Benjamin Pickard, M.P., and Mr. John Wilson, M.P., met those of ~,ranee at Dover to consult on the situation. Mr. Wilson is a level-headed man, and he will probably give excellent advice; but whether it will be followed is another ques­t ion.

THE ELECrRtFICATION OF THE METRO, POLITAN ANDMETROPOLITANDISTRICT RAILWAYS.

(Concluded jrCJm page 690.) ON Tuesday, Wednesday, and Friday, the 12bh, l3bh,

and l 5bh insb., the proceedings in the Arbitration Oourb were resumed and concluded.

The firab witness ca.lled on Tuesday was Professor J. A. Ewing, who declared thab bhe facb that polyphase currents were used in whab he sby led the mixed soheme, for the purpose of conveying power from the generating stabion to the sub-station, was an admission of the efficiency and ad vantage of transmission by polyphase currenbs,

The election of Mr. Will Crooks as Mayor of Poplar n.nd he thought that wha.b seemed to him an entirely un· is a tribute to an honest, fearless, labour leader. No necessa.ry operation-converting them into continuous

1 b d currents-would probably cease to bs performed after a.

higher compliment cou d · e pai to a poor man than time. He had no doubt that with either system the con­t o be elected by the inhabitants of the municipal dibions of the Inner Circle would present difficulties, and borough in which he lives to t he position of :Mayor. in that sense both systems might be described as experi· I t is a testimony to the man's high character, for he mental. He mentioned the Zossen line e.s showing the has no personal means whereby to conciliate the trades- practicability of taking current at very high potlentia.ls people of the district. 1 from trolley lines. For the purpose of transmitting

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Nov. 22, 1901.] E N G I N E E R I N G.

THE BARROW HEMATITE STEEL WORKS.

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power, polyphase currents had very great advantages: one could readily generate current ab a high pressure ; that high-pressure current could be conveyed through con­ductors of comparatively small size, and could be utilised mechanically by motors of a very simple and efficient con­struction. He thought conversion into continuous current unnecessary and prejudicial; prejudicial in two impor­tant particulars : it involved expensive and elaborate ma­chinery for conversion, which meant an addition of capital o:>st, an additional expense in attendanc~, and a loss of current, the rotary converters being a source of loss; besides all thifl , the conversion was prE'j udioial in the senEe that it imposed a. limit upon the pressure ab which the currenb could be carried to the train. With low pres­sures large conductors were necessary. When several trains were starting ao one~, th~ rotary converter would have a very heavy load imposed upon it. Rotary converters, if well designed, would stand alon~, perhapfl, twice their normal rated capacity ; but if a load much heavier than that were applied, they would be liable to go out of phase and to cease working, and it would be necessary to pro­vide a very large margin of power in the rotary converters. He did nob want to suggest that the continuous-current system might nob be capable of working satisfacoorily; but to adapt it satisfactorily to such conditions tt.s ruled on the Inner Circle, it would be necessary to pub down a very large margin for the provision of rotary con­verters, to provide for contingAnoies. Comparing these conditions to those on the Central London R ail­way, Pcof~sor Ewing stated that the acceleration on the latter took place to a large extent in consequence of gradients which were prepared for the purpo:3e ; as each train left the station, in entered a gradient of 1 in 33 downwatds; this alone gave an acceleration without electrical assistance approachmg 1 ft. per second per s 3Cond. With regard to drop of potential, he stated there would be practically none in the system ad vo­cated by Ganz, because of the very small currents in bhe first plac3 and the ea.sy possibility of multiplying transformer s bations. This advantage would increase with the inoreast d length of the line; it would be a. com­paratively simple matter to apply electric traction on a large scale to a long railway when dealing with polyphase currents ab 3000 volts; hub it would be a difficult one when dealing with continuous currents at 500 volts, for in this case it would be necessary to place sub-stations with rotary converters ab short distances along the whole line of railway. He had no expectation whatever of seeing 'railways driven over fairly long distances by continuous current. On the other band, it had very great advantages for tramway service, because it was then practicable to use a. single overhead conductor to carry the current and to use the rails as return. In railways where large our­rents had to be conveyed from the sub-stations, it became practically imperative to use t wo insulated conductors, because if the rails were used as return conduotorf!, the drop in voltage would be dangerous a.<\ regards electrolysis of water and gas p ipes. It would also be a ftlotor in disturb­ing the telegraphs. With polyphase currents it was quite easy to prevent a. difference of more than 7 volts existing in the ra.ili, and the leakage of current into the ground had not the same disadvantage a.s the leakage of continuous

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current had. In both cases one bad to use two insulated conductors, because in the continuous system there were large currents, and three conductors were required in the al~ernating, but ~n the latter it was possible bo use the rails as the thud. So far as the acceleration with continuous - current motors was concerned compared with polyphase motors, the former motor~ used less energy and produced t he same effect on trains; but, on the other ~an~, polyphase motors bad the advantage, when workmg ID cascade, of restoring part of the energy they bad taken. In the continuous-current system a very heavy flywheel would have to be used on the engines, in order that fluctuations in the demand should be met without any material change in the speed. There would nob be the same strict need for observing absolutely ~niform periodicity ~here converters are nob used, and ID that aspect the engmes and generators might be eome­wbat cheaper in the polyphase system thau would be prudent in the other. The American engineer?, according to Professor Ewing, began with tramways, and had con­tinue.d with rail~ays as if they were tramways; the Contmental engmeer~, on the other hand, attacked the railways as a quite new problem, and seemed, according to him, to,have taken a. wise course. With the polyphase system, a practically constant speed was main­tained in the train, both on rising and falling gradients, and whether ib consist€d of a few on.rriages or of a large number, so long as the motors had the power to drive ib at that speed. Aa regards the overhead wires, he had examined the proposals that bad been made for their earthing, and had found them workable; but personally he would prefer to see in long tunnels a. stiff rail rather than the comparatively flexible trolley wires, as a. matter of engineering preference. There would be no possible element of danger bo the passengers and drivers if the methods proposed by ?viessrs. Ganz were carried oub. H e was in favour of the water rheostat, proposed by them also. As bo the small air g-ap, tb was mechanically a perfectly sound thing, prov1ded there were long bearings, properly looked after and lubricated.

l\hjor Philip Cardew, who was next called, stated that the Inner Circle presented different conditions to other electrical railways, such as the Liverpool overhead rail­way, as it was in connection with the whole railway system of E ngland; the third-rail continuous current was nob applicable to lines of considerable length which might have a heavy traffic, such, for instance, as the Mebro­politan line from Baker-street to Qua.inton-road . Until very recently, he had nob looked favourably upon the three­phase system for traction, hub he now thought that with the arrangements worked oub by Meesrs. Ga.n~, the three­phase system would work with even greater efficiency nha.n that with continuous current. Such was his present opinion, but he would lik~, of course, to make tests upon a. railway thoroughly equipped. As to bhe high-tension conductors, if they A.re quite inaccessible, and if proper provision is made, in the event of any rupture, that they should be harmle.:Js before they oa.n touch anybody, there would not be any practical danger, He thought, on the other hand, there was a. certain element of danger in the 500.volt ~ystem. At this point 1\Ir. Parsball asked the

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witness to check the figures given by Mr. Kapp as to the working of the Sondrio-Lecco line, compared to what would be those for bhe Inner Circle. Major Cd.rdew thought the Ganz system of control was both simple and reliable ; he did not see why the liquid rheostats Ehould not work with grea.b satisfaction. He explained from a sketch he made the way in which be would get over the difficulty ab the triangle junctions. In reply to the Umpire, M.ajor Oa.rdew repeated that it would be desir­able, and it would even be necessary, before converting any large length of railway, or, indeed, the whole of the Inner Circle, to equip a. portion, in order tba~ sufficient trials might take place to satisfy the Board of Trade, and to satisfy the advisers of the company, that the system was going to work safely and satis­factorily. The equiJ?menb of the primary high-tension circuit could be oarr1ed out so as nob to be affected by the kind of traction system ul timately decided upon. Be did nob see tha.b it would take more than a. fortnight to make the necessary traction tests on a portion of the line. In his cross-examination Mr. Moulton compared ab great length the respective power of the central station plants proposed by Mesar~. Ganzand byTbomson-Houston. Major Ca.rdew stated that on the Inner Circle one was getting on new ground in the nse of a complicated insu­lated system-the double rails, two insulated rails instead of one. That must lead to certain difficulties, especially ab the points A.nd crossings. In the case of rails, they would have to be cub so that the brains ran clearly through them, as ib were, because they were on the level of the permanent way, while the overhead wires were over the crossing. The Central L ondon was a self-contained railway, while the District bad many other brains coming into ib, and those other trains bad to clear the insulated rails. Referring to the probable action of the Board of Trade with regard to both systems, he stated that owing to the much higher pressure in the alternating-current system, the Board of Trade would require more ex­periments before bsing satisfied that it would be per · fectly safe, than they would require with a. system of which they had already pra.ctlcal experience. With the continuous system the Board might nob insist on trials.

The next witness was Mr. Ernesb Talbob, whose evi­dence bore exolusi vely on the use of overhead trolley wire and its mode of suspension. The oars used by Mr. Ta.lbob were in no way similar to those proposed by Ganz as regards the safety devices pub forward by Mr. Bla.tby. He had no experience ab all of phosphor - bronze

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Professor Sylvanus P. Thompson was the last witness called ; his evidence being of special interest, we repro­duce it almost textually from the official minutes.

Mr. Cripps : To which of the two systems do you give the preference?

Professor Thompson: Decidedly bo the alternating three-phase system. I give the preference to that system in all oases where the necessity comes of using high voltages.

Mr. Cripps : Do you consider we have here a. case where high voltage is in itself an ad vantage ?

Professor Thompson: Obviou~ly, because both sss ~ems

begin with high voltage. A ll the tenders are high voltage tenders to begin with.

Mr. Cripps: Starting at the generating station, you do not draw any distinction between the two systems?

P rofessor Thompson : There is practically none. Mr. Cripps : But when you get to the sub-stations, the

two systems differentiate? P rofessor Thowpson : Yes. They begin with steam

Pngines which drive three-phase alternators working at a high voltage. T hose alternators supply three-phase alter ­nating o~rrents to the cables, and the cables bring those currents, as three-phase high-voltage curren ts, to the place where they are to feed-the distribution of which­ever kind.

Mr. Cripps: There, as we know, we have in the case of the continuous system. the rotary converter?

Professor Thompson: But before that there are trans­formers to t ransform down from the high voltage at which the currents are generated to a. lower voltage. There are stationary transformers in both cases for that. Then, in the continuous case, comes io the rotary converter and its accompanying nece~sary switch gear supplying the continuous-curren t line.

Mr. Cripps : Y ou have the rotary conver ter and the larger conductor upon the continuous-current system? Profe~sor Thompson : Y C'S' . • Mr. Cripps: Do you look upon it as an advantage in

itself to get rid of the rotary converter ? P rofessor Thompson: Yes; distinct.Jy an advantage. 'IYir. Cripps : Apart from the question of cost ? Professor Thompson: Yes; the introduction of it is in

itself a complication. You ~eb back one step further to simplicity by doing without 1t.

Mr. Cripps: What do you say a-s regards having the conductor on the rail level ?

Professor Thompson : T here is a. certain amount of danger in that, and there is a certain loss of energy also, which reduces the efficiency of the system as a. whole.

Mr. Cripps : What is your esbimate of the loss of energy in the conducting rail ?

Professor Thompson: That depends upon how many places there will be with sub-stations with rotary con­verters. It may be 6, 7, 8, 10, or 20 per cent. loss.

Mr. Cripps: Take seven or eigh t sub-stations? Professor Thompson : If with seven sub·sta.bions, I

estimate the average loss in th~ rails would be 8 per cent., or might go np to 12 or 13 per cent. at the maximum, taking the ca~e of a train in an unfavourable position.

Mr. Parshall : How many trains was t hat ? Professor Thompson: That is assuming the full service

- 40 t rains. Mr. Parsball : What is the average star ting power taken

by the trains ? P rofessor Thompson: 780 kilowatts. Mr. Parshall: So that taking 780 kilowatts a train-mile,

that only gives you 150 as an average a train ? Professor Thcmpson : I am taking the voltage at 750. Mr. Cripps: I thought you were taking the maximum? P rofessor Thompson: The average I took asS percent.,

with seven sub. station~. Mr. Cripps : What are the 780 kilowatts applicable to ? P rofessor Thompson: The average demand of power

p er train. Mr. Cripps : I s there any other source of loss besides

this which you say might be from 8 to 12 per c<;;nb? P rofessor Thompson: I have mentioned the loss in the

rotary converters. Mr. Cripps: Did you give the amoun t of that loss? P rofessor Thompson: No, I have nob stated that. I took

it as being from 7 to 8 per ceub. Then there are the commutators on the motors on the cars, which will lose, perhap~, half of 1 per cent.

Mr. Cripps : What would be the totalloes in the con­tinuous-current system ?

Professor Thompson: I make it somewhere about 16 per cen t. There are som~ losEes that we would hn:ve to set against that in t!:te polyphase syst~m. There I S the loss in our copper mam overhead and ra1l return, an_d that will amount to about 1 per cen t. And then our stationary transformers will either have to be a. little more costly than their stationary transformers, or, if not more costly, they will lose a. little more energy; hub that is not much.

Mr. Cripps : What would be the correspo~ding figure ? Professor Thompson: About 3 ab the outside. Mr. Cripps : Ther~fore there ~ould be 13 per cent. ,

according to your view, to the d~advantage of the con­tinuous.ourrent system ?

P rofessor Thompson: Yes. Mr. Cripps : W ould you give .us, as the result of

your experience, what YC?U consider as regards the efficiency of the motors designed here for the polyphase system?

Professor Thompson : Taking s~mply motors. as ~otors, for a given s1ze, and the revolvmg part (which, m the case of a continuous current, you call an armature, or in the case of a three-phase ~otor, Y?U ge~era.lly. call a rotor) in a motor of equal s1ze, mov1!lg w1t~ a gtven speed the driving effort, or the torq ue, 1s practically the same 'for each, provided . yo~ design them to have the same efficiency. T here IS httle to choose b~tween t~e two motor for motor. So far as the revolving part I S

con~erned the same size of revolving part can be de-signed to do equal duty in either case. .

Mr. Cripps : A re there any .advantage~ ID the three­pha-se over the cont inuoue, or ID the contmuous over the three. phase outside that ?

P rofessor Thompson: They have different peculiarities, and t here are several distinct advantages th~t may be named for the polyphase motors. In the fi rst p lace,

· ven the size of the revolving pf!-rb ~or a. given wo~k, fn the case of th~ polyphase maohme Ib w1ll nob reqmre the outer stationary parb to be as heavy as the outer

E N G I N E E R I N G . .

stationary part in the continuous-current motor. In other words, the stator of the three-phase will nob be as heavy as the field magnet of the cont inuous. Then it can be used with a much smaller clearance than the continuous­current motor for the same power of speed. Then it requires less attention from time to time, because it has no armature. It has merely solid connections on slip rings. The con t rolling gear for starting and running the motor is far simpler. ~Ir. Cripps: Are the controllers used on the Cen t ral

L ondon simple or complicated? Professor Thompson : They have a large number of

notches on the manipulation part. They have, if I have counted them right, 72 different electrical parts on the inside, which may be grouped in various ways, and they consist of some hundreds of parts put together. This oar­controller is a highly-organised, higbly.complicated con· trivance. It has grown up from the con t rollers of train cars, which have been developed time after time in di ffe­rent ways, and have settled down into a. re~ula.r well­known piece of apparatus, highly complicated mside, but which works marvellously well in spite of its complica­t ion. The polyphase controller is far simpler.

Mr. Moulton: You sa~ the Ganz is simpler ? Professor Thompson : Distinctly so. Mr. Cripps: I s the operation of cascade of importance

and advantage ? P rofessor Thompson : The advantage of the cascade

system of grouping is that while actin~ as a brake it enables you to recover a portion of the kmetio energy of the train and return it as electric power on to the line. It brings the three·phase motor to a position in advance of the series parallel ; it enables you to do what you cannot do with the · series parallel arrangement. It enables you to work during the period of acceleration with nearly double acceleration during the first half of the period. Thab is a greab advantage. For the same given time of acceleration, it increases the distance run. It enables you to get up quicker to the top speed, because it enables you to work with a. rather less top speed than in the case of the series parallel of a continuous motor. The con­troller in the series parallel for getting acceleration is more complicated than in the three-phase. The three­phase induction motor is automatic in its action in this sense: there are two elements oo it-a stationary part to which the primary current is brought, and the revolving part; when you turn on the current, by switching on the primary on to the stationary par t automatically, by the process called induction, you have the large correspond­ing current in the secondary part. Or, in the case where the primary part is left on the hi~h- tension mains, the moment you allow current to flow through the secon­dary part automatically, current comes from the line through the primary part, and both elements are strength· ened, and you geb the lar~e n£cessary torque. The turn­in~ force, other things being equal, depends upon there bemg strong currents in both parts.

Mr. Cripps : What do you say as regards the overhead system?

Professor Thompson: Personally I have never been favourable to overhead wires, whether for telephones, electric lighting, or tramways, and i t is pretty well known that I have spent thought, time, and money in endea­vouring to show that a tramway can be operated without overhead wires. But my view is that if there is any place where overhead wires can be tolerated, it is on a. rail way and in a tunnel.

Mr. Cripps : For running into the country from the Inner Circle, would any other system be possible than an overhead system?

Profes'3or Thompson : I think not for long lines in the count ry. But quite apart from the question of connec­tions to outside long lines, my view is that the Circl~, if it stood alone, would be worked best by overhead wires. The overhead wire would also be more conducive to safety. I have seen two tunnels where wires were put overhead for the purpose of giving current to oar~ moving below. The one is the Jungfrau Railway-three-phase.

Mr. Moulton : How long is that? Professor 'l'hompson: Nob much more than 2 miles; I

bhink it is about 3 miles. Mr. Moulton: It crawls up a hole in the mountain. Mr. Cripps : A_s regards the p~oblem of attachment of

a wire to a roof, ts the problem different whether you are crawling up a hole in the mountain, or round the Inner Circle? .

Mr. 1\1onlton : Nob, I agree, if you are crawhng round the Inner Circle.

P rofessor Thompson: The difficulties are difficultie3 of degree, notJ of kind.

M r Cripps : Where is the other case? Pr~fessor Thompson : The other case is a short tunnel

under the River Spree-ab Treptan Tunnel, a few miles out of Berlin, less than ha:lf a mile long. .

Mr. Cripps : Do you thmk there can be an~ dt~culby as regards the attachment of the overhead Wire m the case of the I nner Circle?

Professor Thorupson : I do nob imagine that there can be any difficulty that is unsurmountable by the wit of man. Ib is a. simple engineering job.

Mr. ~Ioulton : Or the money of man ? P rofessor 'fhompson: It is a. simple engineering job.

It is also simpler to maintain insulation in d:oub.tful places with alternatJmg current_, because damp, which 1s a source of leakage is dealt wtbh differently. The continuous current el~ot~olyees the film o~ moisture, a~d produ~es chemical aot10n ; the al ternating current Simply dnes it up. . . . .

Mr. Cripps : You have VISited, I thmk, several eleotnc th ree-phase lines?

Professor Thompson: I have visitErl several that have been mentioned here. The Burgdorf-Thun line and the Jongfrau :Railway. The clearance ip the motora i~

[Nov. 2 2, 1901.

2 millimetres, with which clearance they work perfectly well .

Mr. Cripps : Do you think the placing of the exciter on the end of the shaft of each generator a proper device ?

Professor Thompson : That is modern practice ; I think it distinctly preferable to the older arrangement of having separate exotters.

Mr. Pa.rshnll : You say it is modern practice. Will you tell me an installation in E ngland where it is used ?

Professor Thompson: I am thinking rather of some larger installations.

Mr. Pa.rshall: There have been some large ones pub in use in the K ingdom during the last year or two?

Professor Thompson: I have never seen them. Mr. Oripps: I think the separate exciters may lead to

more serious results if you have a breakdown, may not they ?

P rofe:s1r Thompson: They did in the c~e of the City and South L ondon Station. On one occasion, ab a time when the excitation was entirely separate, there was a shorb-circuiting which occurred on the bus-bars of tJhe exciting circuit, with the result that the whole of the alternators for the moment lost their current from the field magnet. If each alternator bad had its own par­ticular exciter on the end of its shaft, that would ob­viously nob have occurred.

Mr. Parahall: You know they pub that in ju3b &'i you said ; it was an absolute failure ; they bad to sor11op the machines.

~Ir. Cripps : When was that? Mr. Parshall: Within the las t few years. Prof~sor Thompson: I was nob aware of it. ~Ir. Parshall: I designed the exciters. Mr. Cripps: You are not aware of that, and we must

take your evidence for the moment. Professor Thompson : But I do know very wen the

accident that happened from having the exciters aJl pub on to bus-bars.

Mr. Moulton: Potting all your excibers on to one bus­bar, instead of having each on tJhe end of i ts own al ter­nator!

Mr. Cripps : You visited some of the larger Conti­nental power stations in order to see what the modern practice was ?

Professor Thompson: No; I did not visit them for that particula~ purpose.. I kn~~ . them ; you had only to look at those m the P~triB Exhib1t10n to see how many of them were made in that way.

Cross-examined by Mr. Moulbon: Mr. Moulton: D :d you take the average p~wer for

driving the train ab 780 kilowatts ? P rofessor Thompson : Yes ; 780 kilowatts. Mr. :rt1oulton : I put it to you it is 160 ? Professor Thompson: Well, if ibis-What? M r. Moulton: Then, if there is a mistake of ab:m t

5 to 1 in your data, your calculations are not much to be relied n pon ?

P rofe3Sor Thompson: Yes. :Mr. Moulton: They are; they can stand a litbl3 trifle

of that kind ? Professor Thompson: I will re-calculate if you wi:-h. Mr. Moulton : You have taken 7 to 8 per cent. fvr loss

in the rotary converters. That is much too much. Professor Thompson : No, not for an average. Mr. Moulbon : I mean the actual loss is not so great.

H ave you ever found out? P rofessor Thompson : No ; I cannot tell you. Mr. Moulbon: Where did J·oa get this 7 or 8 per cen t.

from? Professor Thompson: One has data about various

machines. Mr. Moulton: I am talking ab:mt large power stations. Professor T hompson: I have been taking converter3

such as are on the market. Mr. Moulton: Have you ever found what the loss ii ab

large power stations? ProfeE~Sor Thompson: No ; I cannot bell you that. Mr. Moulton: The Inner Circle is a line with fre­

quent stops, and for such a line the three-phase is nob suitable ?

Professor Thompson: On the contrary, I regard it as more suitable, because of the excellen t accelerating pro­pErties of the concatenated motors.

Mr. Moulbon: Now I am going to read a passage from a. book by Sylva.nus P. Thompson, D.So., B. A. , F.R.S., M.I.E.E.; it was written in 1900 : " ... Ib may be taken that for short lines of, say, under five miles, where frequent sbart ings and sboppin~s and very variable speeds are the rule, better resul ts Wlll be ?btained with con­tinuous currents. If the power sbatwn has to be (from consideration of smoke, ven tilation, water, and cooling) a long distance away, and the train or r~ilway is short and of this character, then the best system 1s undoubtedly a combination of the t wo-that is, the generation of high­pressure three-phnse current distributed to rotary con­verters Rlaced along the line. These feeding the latter at 500 or 600 volts, there will, of course, be a loss in the double conversion and increased cost of maintenance. But as a general rule, these disadvantages would be more tha~ balanced by the advantages ~ccruing fron;t the use of standard material and cheaper bne construction, and the best possible speed regulation and starting con brol.,

Do you agree with that? . Professor Thompson: It was true when I wrote tb.

~lost certainly. . M r. Moulton: I p~t i~ to ~ou that you ~nnot, wtthoub

experiment and familia.nty w1th the motor 1tself, prophecy what the heating of a. motor wi.ll be ; . .

Professor Thompson: Not 1f you had to begm Wl~b an entirely new type of motor. But when you have des1gned and built mobors of a. given type, then you are able to calculate what a new one of that type will do.

1\!r. MouHon : I pub it to you even then, it is very

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difficult, indeed, to foretell what the heating of a motor will be ?

P rofessor Tbompson: There are difficulties, but they are nob insuperable.

}.fr. ~foulton: And the question of efficiency depends largely on the heating ?

Profellsor Thompeon: Partly on the heating. Mr. Moulton : As a matter of facb, the clearance cnn

be considerable. Can be up to t in. in the continuous motor without i ts causing nny lo3s '?

Professor Thompson : Without its causing any losP, bub there would be cerbain advantages if ib could be made somewhat smaller.

Mr. lYfoulton : To geb anything like practical results from the alternating motor, you must work ib with a small clearance like 1 '~ '?

Professor Thompson: Yes, certainly; if you mean to use it in cascade, for traction.

}.fr . ~1oulton: I pub itJ to you that collectors give q uite ag much trouble now as commutators in practice ?

P rofessor Thompson : I do nob agree with you. ~lr. Moulton: You are very much against overhead

wires, are you nob ? P rofessor Thompson: Yes. Mr. Moulton: Apparen tly, in the evidence you have

given, if you are in a tunnel you ought to use them, and 1f you are nob in a tunnel you must use them; is that what you say'!

P rofessor '£hompson : No. Mr. Moulton : In the lines outside the Circle you say

you would use the overhead wires ? P rofessor Thompson: Yes ; economic considerations

oblige ib in long line!:'. \Vith regard to suburban lines, ib would d epend upon thei r length. For suburban lines of, say, 20 miles altogether, I should certainly u~e over­head wires.

Mr. Moulton: Would you ever use anything but over ­head wires on a. rail way ?

Professor Thompson : I am n ot sure that I should on a railway.

Mr. Moulton: Therefore, your partiality for overhead wires does not lead you largely to ind ulge in them ? Prof~sor Thompson: I ehould try to get rid of them

everywhere else. Mr. Moulton : '£be trains in the Treptau Tunnel slow

down ? Professor Thompson : They go down an incline at one

end and up an incline at the other. I do nob know tha.b there is any reason for them to go more slowly in the tunnel.

Mr. M oulton : In the J ungfra.u, when you ara taking current from the lin~, you are going very glow]y? Prof~sor Thompson: About 12 miles an hour, I should

think. Mr. !Yfoul ton: That is half speed. My memory of

steep lines like tJba.tJ would nob tell me that you went a mile in five minutes ?

P rofessor Thompson : Ib i.ca difficult to estimate in a tunnel. I could nob really speak con fidently.

Mr. 11oulton : A nd when you come down ? Professor Tbompson : You come down ab about Lhe

same speed-2 per cenb. quicker. You do nob want any large amount of power then ; you are forcing back vower into the line when yon are coming down. There ts the beauty of the three-phase plan: up hill and down hill t he same speed. ~Ir. Pt~.rsball : The same speed, barring the slip ? P rofessor Thompson: W i thin 2 per cent. Mr. Parshall: 2 per cent. slip ? Prof~sor Thompson : That would make 4 per cent. Mr. Moulton : Those are nob oon catena.tions ? Professor Thompson : S ome of the motors are by

Brown, Boveri, and Co., and some by the Oerlikon Com­pany.

Mr. Jr!oulton : I believe thab it is well known that Brown, Boveri, and Co. h ave tried oonca.tenation, and they ea.v that i t gives worse results than the simple apparatus?

Profeesor Thompson: I ha Ye n on seen their letter;* I do nob know what they have written.

Mr. Moulton : But you know pretty well what I re fer to? P rofessor Thompson : I heard you sny something in

c .:>urt ab an earlier stage. Mr. ~Ioulbon : When you go awa.y, yon will have the

curioaity to see whether they did say so or not ? P rofessor Thompson : I do nob know. We shall all

have curiosity when we leave the Oourb. M r. Moulton: In the case of the breakdown on the

City of London, all the exciters bad gone through one common bus-bar ? Profe~sor Thompson : Yes. :Mr. ~[oulton: A nd made one exciting system, and

there was a short oirouib in that exciting system ? P rofessor Thomp~on: Y€s. ~Ir. !Yioulton : I t was nob a question of t here being

separate exciter~, bub their current united before i b wn.s used, and this affected the whole of the generators ?

Profeasor Thompson: Yes; it was the circumstance that they were on omnibus bars.

~[ r. M oulton: They took the remedy, you say, of putting on an exciter to each, working actually with the unit CJ f plant?

Professor Thompson: I do not know that they went through that for the whole of the station; it was done for certain machines.

Mr. Moulton: I put it to you that that was thrown out again ?

Professor Thompson: I am nob aware of it. ~fr. ~Loulton: If you have only three sets, each with

its own exciter, if one ex<.iter gets wrong, then the whole of thab machine is gone ?

P rofessor Thompson : No; because you can still use in -

* See ENGINEEJUNG1 vol. lxxii. , page 626.

E N G I N E E R I N G.

emergency the curren t from one of the other exciters to excite a second alternator.

Mr. ~foulbon : Then you must run an alternator just for the sake of the exciter ?

])rofessor Thompson: Presumably, you will always be running one altornabor. At the minimum time when there is less demand there will be ab leasb one alterna.tor running. Therefore there will bA one exciber rnnning, and that exciter, on emergency, oan supply·--

Mr. Moulton : I am speaking abonb the normal time; you will have two alternators runnins: ?

Professor Thompson: Then you wlll have two exciters running, and those two exciters could each of them, on emergency, supply two other alterna tors.

Mr. ~Ioulton: Bub they could only supply if you kept one of the units going for the sak e of its exciter '?

P rofessor Thompson: Ob, no. ~Ir. Moulton : Ob, yes. Profes:!or Thompson: One exciter can be arranged; you

can arrange one so tha.b it shall feed two alternators ab the same time.

Mr. Moulton: These are designed only to be sufficient to feed one alternator ?

P rofessor Thompson : That depends whether they are designed to meet emergencies.

Mr. M oulton: If you are running them independently, you oan vary the work they do ; but if they are attached to the generator on the same shaft, you cannot ?

Professor Thompson: Oh, ye3, you can ; you oan vary the amount of work you take out of them.

Mr. Moulton: You cannot vary ib so as to i ncrease the current on the same potent ial ?

Professor Thompson: Yes, you oan. Mr. Moulton: You would not have much liberty of

adjustin~ them when they are working. Y on cannot vary thetr speed without varying that of the alternators and otherwise ?

P rofessor Thompson: Y ou do not want to vary their speed. Ib does nob matter to a given exciter that is to be driven ab a given speed, and bo ~ive out currents, whether it has a separate steam engme to drive it or whether itJ is driven on a shafb that is also driving some­thing else.

Mr. Moulton: If it is d riven by a sbo.fb that drives the alternator, its speed is limi ted and fixed by the speed of the alternator ?

Ptofessor Thomp.qon: So it would be by its own engine if ib were a sepa.rabe engine . You would want to alter the speed of that engine.

Mr. Moulton: Nob if you wanted to make it excite two alternators ?

Professor Thom pson : No; you would si m ply have twice a~ m uch current from ib. If you want to put two lamps on a machine instead of one, you do nob have to run that machine quicker; you simply take more current from the machin~.

Mr. ~1oulton: What I suggest is thab if you put the E'xciter of a.n alternator on its own shaft, you cannot use that independent ly as you like for the other alternators ?

P rofessor Thompson : There is nob the same amount of i ndependenoe.

Mr. ~foulton: That is exactly what I have said. With regard now to the astonishing statement bha.b the alter­nating con trol is simpler. First of a ll, you have ne,·er yen seen a conoatenated system under cont rol, have you ?

Professor Thompson: If you mean for traction, no. ~Ir. Moulton : In has n ever been ueed for anything

else? P rofessor Thompson: I have nob seen ib in use for any

purpose. Mr. Moulton: The control of the series parallel has

been completely worked oub, and ib simply means chang­ins: certain connections of fix~d resistances and fixed ootls?

P rofessor Thompson: Yes, it does mean that. Mr. Moult.on : All embodied in one handle? Professor Thompson : One handle for the ordinary

control, and another handle, if need be, for reversing. Mr. Moulton : As you say, ib took years to evolve that? Professor Thompson : It took years bo develop it, and

now it works very satisfactorily. Mr. M oulbon : L ot me take the other control. What

do you mean by eaying ib is simpler ? L et us see what facts there are. First of all there are fluid resistances. You never heard of fluid resistances being used for trac­tion ?

Professor Thompson : For traction, no. Mr. M oulton: These fluid resistances have bo be driven

in by air pressure ? P rofessor Thompson : They are in the case of the pro­

p osed arrangement. They can be used otherwise ; they ha ve been used for years otherwise.

Mr. Moulton : Tha t a ir pressure is due to the leakage from a reservoir of compressed air throu~b a small hole. Do you can that an uncomplicated thin~ m construction '?

P rofessor Thompson: It simplifies bhmgs very much to have that pneumatic arrangement, instead of all the innumerable contact devices that there are in an ordinary oar -controller.

Mr. Moulton : If the pressure varies ab all in the reservoir, the resul b will vary ?

P rofessor Thompson : If the prel:sure varies ab all in the reservoir, that will mean a different heighb of liquid in the interior, and a different rate ab which ib mounts. ~Ir. ~[oulton: Then ib is a small orifice; and if any­

thing like dirb gob into that orifice, it would make a serious di fference in the moving of the resistance ?

Professor Thompson: I do nob say a serious difference. Mr. Moulton : We can judge for ourselves how serious

it would be. Have you seen even a diagram of the actual mechanical arrangement of this suggested control ? Also a rliA.gram of the oonstruntion '?

Ptofeesor 'l'hompson: Yes.

Mr. Moulton : 'Vhy were you more favoured than Major Cardew ?

Professor Thompson: I do nob know. I tbougbb he had seen itJ.

}.fr. Moulton: Ca.n you tell me, within one or two, how many ball-cooks there a re in ib '!

Professor Thompson: In whab I saw there w~ o.ne ball-valve rising and falling on a lever-whab we ordmarlly call a. ball-valve.

!Yir. M oulton : Oh, bub I thought they had nob so shamelessly preferred _you to the other witnesses:-th~tJ is a very early form. That is whab we call an archatsm 10

this a rbitration. Why, thab must have been two days ago; we are in a different century now. D o you know what other ball-cocks they have ?

Professor 1,hompson: Besides, there was a very small ball -valve in the bottom- that is to say, a. little boxwood ball to rise and fall- an ord inary ball-valve.

Mr. Moulton : A very nice sort of thing for delicate work, when you are jostling along in a ra ilway train?

P rofessor Thompson: An admirable thing is a ball-valve in a liquid.

l\Ir. Moulbon : But I am talking about it for g raduated work. I s bhab the sor t of thing which you say would work well under the oirumstances of t raction ?

Professor T hompson : I say it would do admirably to let the liquid outJ quickly. ~fr. 1-foulton: Would you or would you not, before you

tried this in a huge system, like to eee whether it did work or nob ?

P rofeesor Thompson: Yes, certainly. All these things ought to be tried, whoever makes them.

Mr. M oulton: I s there a solenoid there? P10fessor Thompson: Ye!'. Mr. M oulton : Can that open the orifice more than

what I call the n ormal amounb ? Professor 'rhomflSOn : Ib can. Mr. M oulton : D o you call that control ? You agree

with me that if o.nytJhing went wrong there, the rate a.tJ which the resistance was switched outJ would differ widely from the intentions of the maker ?

Professor Thompson: ItJ would differ, but not neces­sarily very widely.

~Ir. Moulton : Bub it would differ'! P rofessor Thompson : No ; I am nob even sure ib would

differ from the intentions of the maker. ~ir. Moulton: The maker intends these litble varieties? Professor Thompson : The thing is done to have a cer­

tain, as you pub ib, normal operation, but the thing is a lso under con trol in various ways.

Mr. Moulton : Yes ; but we were told thab no control could make the resistance go outJ quicker. It could only make it go out slower. Can you make ib go out quicker ?

Professor Thompson: I am nob sure tJhatJ I can ans wer your question right off. I musb think.

Mr. M oulton: This is t he simple control which vou have been favoured with a sight of ?

P rofessor Thompson: I do nob want to answer you o.nd give a wrong ans wer. (A pause.) The solenoid ca.n certainly open the port above the n ormal amounb.

Mr. Moulton : Therefore it can let the whole of this resistance oub q1.1icker t han the normal run ?

Professor Thompson : Slightly quicker. Mr. M oulton : What do you mean by slightly ? Sup­

posing ib goes wrong, then this resistance may go oub ? Professor Tbompson : In a rather shorter time. Mr. Moulton : What do you mean by a. rather shorter

time? Come now, say 7 or 8 seconds is the normal time. I do nob know whether that is right ? Profe~sor Thompson: I can guess-5 or 6 seconds, or

7 or 8. Mr. M oulton : H ow do you know that? Professor Thoropson: Because the liquid, even ii you

give ib a wider opening, does nob necessarily flow quicker because of that opening, in proportion to tpe wtdth of that opening. There are other oases of liquid friction.

Mr. Moulton: You mean to say you a re trusting to the air paasing th rough the small orifice, and yet nob obeying the laws of liquids that flow through an orifice. Do you mean that if you open that orifice wider, the air will nob pass through ?

Professor Thompson: The air will go through quicker, cer tainly.

~fr. M oulton: And then it will d rive the water out q uicker ?

Professor Thompson: Yes; but the rate a b which the water will move up and down depends upon the friction in the path that it meets wibh; and if you increase the pressure, you do nob get the rise of water exactly propor­tional.

}.l!r. 1-Ioulton : In fact, your hope of salvation is that you have a disobedient servant in the water ?

Professor 1,hornpson : No. :Mr. ~Ioulton: I will bake it at five or six, because it

really does n ob matter. Therefore the quickest it could be switched in is five or six seconds ?

Professor Thompson: I will nob undertake to say that even. It is only a guess.

Mr. M oulton : B ut, really, you have told us that this system of con t rol is so much simpler than the series­parallel one. What do you mean? You do nob mean to say ib is mechanica lly more simple ?

Professor Thompson : E lectrically, it is much more simple.

A'Ir. Moulton: I should like to know what electrically simple means. Thab is to say, if you had no difficul ties mechanically, the one would have a simpler dia~ram than the other'!

Professor Thompson : N o ; it would be much simpler in the construction of the electrical parts-many fewer parts.

~ir. Mtlulhon : How many parts has a pint of water, I ~:~hould hke to know ?

'

•

•

Professor Thompson : As many as a lump of brass I expect. '

Mr. l\1:oulton: But they do not walk quite as much in step, do they ?

Professor Thompson: No. . Mr. Moulton: Y,ou are nob quite sure whether or nob 1b c_ould go out qutcker; but the whole question of the tram control depends upon that, does it notl ?

Professor Thompson: Nob the whole question. Mr. Moult~n : A gr~ab deal of it ; the question of

whether that IS a uboJ:!labtc control or whether 1b is under the control of the dn ver, depends upon that little item ?

Professor Thompson: To some extent. Mr. ;¥oulton:. It ~s something ~ore than "to some

extent.. Supposmg 1t must take 1ts normal time then the drtver oann<?b accelerate the time during whi~h he passes through hts first stage ?

Professor Thompson: Oh, yes; he can. Mr. Moulton: I thought the great beauty of this was

that he could . nob; ~nd I hear somebody saying-it sounded to me hke MaJor Cardew's voice-" That is the very reason we have it." Ara you sure he is intended to be able. bo make . it go. quicker. I remember Mr. ~lathy saymg the pomb of 1b is that though he can make 1t go slower, he oannob make it go quicker ?

;J?r<;>fessor ~h~mpson: He cannot make it go quicker wtbhm certam bmtts.

Mr. Moulton : Come now? Professor Thompson : I do nob think Mr. Mculton

you have g rasped the first principle of this control. ' Mr. Moulton : You are quite right, but, in self­

~efence, I must say I have done my besb to. I will leave 1t there.

Re·examined by Mr. WallB~ce : In this re-examination, Professor Thompson stated that

ab the time he wrote the book quoted by Mr. Moulton he h.ad nob in his min? any use of three-phase motors except stmple-nob two m cascade. The cascade system was kn?wn to him vaguely, bu~ be did nob know the advantages of tb. As regards the heabmg of motors, it would be a mere mabber of calculation.

The Umpire : What is bh~ field in which your con­version to overhead wires operates ?

Professor Tbompson: Wherever they could either fall upon the public or where other wires could fall upon them. I have for years objected bo all overhead wires on principle for that very reason, bhab there is a certain public danger in wires that go over a place that is accessib~e bo the public, or wir~ that are crossed by other wues; and the one place, m my judgment, where they may be used without introducing any danger is in a tunnel or on a railway. I have given in evidence several times in past years my views that all wires should be underground. 1 have been looked upon M somewhat of a black sheep in th~ engineering profession because I have taken that view very strongly.

With regard to the system proposed by Ga.nz for con­trol, Professor Thompson stated that it was a very effi­cient piece of electromagnetic mechanism, and one which curiously works better if it is subjected to vibration, beor:a.use the moving part~ are less liable to stick. .

Mr. Wallace: Assummg that the controller dtd go wrong, would there be any injurious result ?

Professor Thompson; No. Mr. Moulbon: No injurious result ? Then bhe control

is simple. If on the control going wrong there is no bad result, then the control is triumphant ?

Mr. Cripps, K.C., M.P., then proceeded to sum up the case on behalf of the Metropolitan Company. He en­tered ab great length into a comparison between the bwo systems, and pointed out the var10us advantages in favour of the albernating-current one, stating that the Metro· p')litan Company had very large interests involved, and ha1 made up their own mind as to the system they thoughb should be adopted, on the i'round of cost, efficiency, and safety. The effoot of the decision come to might b~ bo pub upon the predominant partner a syatem they believed to be wholly inferior. He referred to the figures given by Mr. Blathy as to the saving which would be effected in using the system ad­vocated by Ganz, both for the Inner Circle and for lines running to the outside. For the latter, anything except the overhe&d wires would be quite prohibit1 ve as regards cost. The outside lines were a factor that should nob be pub out of sight. As regards safety through, say, a broken wire, and looking ab the matter from a common­sense point of view, was it conceivable one could nob succeed in eliminating all risk in the present condition of electric science? Whether overhead wires were put up in the tunnels or n ot, all repair work could only be carried out when the line was nob running, . as is done even now with steam traction. The Metropolitan Company were anxious to have a system and an equipment which, they wera advised, were almost absolutely essential when one gets outside the Inner Circle. As to acceleration, it was a great advantage in the direction of efficiency to get the greater accele­ration during the firat half, as was claimed with the ca~oade system. With regard to the .question of the " untried,, he recollected what bad been ab the time the criticism on the Forth Bridge case. This and that diffi ­culty was suggested; it was said that Sir William Arrol made something like 10.000 designs of novel devices in order to get over the difficulties of that construction. Of course he did get over them, and all honour to him. On the point of efficiency it could nob be suggested there was any factor in which the polyphase system would be behind the continuous-current system. It was more simple and eliminated to a greater extent the human element. Where was the novelty in its essence and in its substance? They were simply applying well­known well-ascertained, well-tried, well-experimented­upon principles. It was true that they were applying

E N G I N E E R I N G.

b~em to the solution of a new problem. So were the con­tmuous-ourrent people. The novelty was the Inner Circle.

!dr: Moulbon, K.C., M .P., who spoke on behalf of the D1stnct C<?mpany, stated that both parties were agreed that the du~ob current was perfectly capable of doing the work wJthout _any engineering or electrical risk at all, bhab the experience we bad acquired made ib quite safe and cerbam, and therefore both parties were ag.reed th.ab it was wise and prudent to change these rallways mto elec~rical railways on the direct system. But the Metropohtan Company bad proposed another cours~, they thought more wise and prudent and the Umpt.re had to decide. The point that the w~rk could be done safely and efficiently by the direct current was no~ even challenged. But it was said there was another system so good that it was wiser and more prudent to take it. 9ne immediately asked whether there were two systems m use. The answer was practically " No., There was not. a single yard worked by any other system hub dueob current. It had been chosen years a.go, perfeo~ed by experienc~, and it holds its o~n wtthoub a rival. Therefore one started with th1s t<;> the go<?d, that experience had perfected it, and made tb a certamby, and experience had not begun to be formed on t~e other. To go and pub an untried system to work, as tbs fir.sb work, probably the heaviest and most congested traffic m. the world, where phe interruption of traffic was most serious, appeared to htm so much the re­verae of prudence, that he had great difficulty in treating wit~ due .forenaic courtesy the arguments that were pub agamst htm. If be knew a really shrewd man who had wanted to put his money in the polyphase system, and if he had _wanted that man nob to adopt the ad vice of the other stde, he would have gob him to hear the evi­dence of that exceedingly able witness, Mr. Bla.thy. T~at man would have said : " Why, Mr. Blathy bhu~ks. that when a .thing is on paper ib is as good as 1f 1b had been tned; Mr. Blathy's mind does nob see anv value in experience. Keep me from such an ad-. ,, M B v1ser. r. lathy bad a. half-tried system · he had tried _it on a mile of .tra.c~ ab Budapest, and bad made experimental runs Wlth 1t ab Sondrio. But so little he valued having tried a. thing that he bossed the whole of th!Lb over for something which on paper had fairer pro­mises. What would be the cost of the failure of a safety appliance on that mile of track at Budapest? Ou the U nderground it would mea.n the loss simply of 1000t. to 2000l. c:>f fares, a complete interruption of traffic, and the feehng that the engmeers are not to be relied upon. To refuse to have an untried system under such conditions h&:d nothing to do with one's belief in the growth of s01enc~. It was utter~y unscientific to attempt tlo develop anythmg new under Circumstances where experiment was ab all costly, and therefore we dared nob risk experiment. The Central London was on the direct-current system · ib had not had any electrical difficulty; the vibratio~ difficulty was due to its locomotives, because the system ~ad de12_arted in their construction from the ordinary prac­tiCe. He compared ab great length the Ganz tender with the other tenders, statmg that the normal output of the Ga.nz plant ought to have been stated as 5400 kilowatts, and nob 14,000, as against the Thomson-Houston 10,000. He demonstrated also that the system ad vooated by Ga.nz would nob be cheaper to work, owing to the difference in the acceleration now proposed and that tendered for. The whole Ganz scheme had been changed, both in figures and in form. The General Elecbric Company, the largest electrical manufacturing concern in the world, had come to the conclusion that, under equal and ordinary circum­stances, the direob-current system was cheaper to instal and to work than the polyphase. That company ad­mitted that very long runs at a uniform speed would be congenial work for the polyphase; but in all oases where the polyphase would be ab a disadvantage, the worst would be where it had very little time to run ab top and uniform speed, where ib had bo start and sbop frequently. The alternating-system ad vooates abuse the converter&, hub they would be taking about in their system some­thing like 320 tons of motora which were not used the greater part of the time. He did nob want to make it a q_uestion of prejudice, hub the case on the Metropolitan stde had been pub forward by those most interested in the commercial success.

The addresses very briefly reported above concluded the proceedings.

The Umpire stated, on taking leave, that this was not an ordinary case, where one bad two arbitrators differing and an umpire called upon to do his best himself. The Act of P41.rliament said that tbe special tribunal should report to the Bos.rd of Trade. The decision might be a little longer than it would have been if left to a sin~le individual.

In the course of the proceedings var10us railways have been mentioned. We may state we have described them fully in TRACTION AND T RANSMISSICN, as follows:

"The J\IIultiple U nit System of Control in America," vol. i.h page 24.

" T e Paris Mebropoli tan Electric Rail way,, vol. i., p~ge 89.

"The Paris Exbension of the Orleans Railway," vol. i., page 225.

"The Burgdorf- Thun E lectric Railway,, vol. ii., page 32. "Hi~h-Speed Elecbric Traction in Germany ,, (trials on

the mihtary Berlin-Zossen line), vol. ii,, pages 42 and 152. Vol. ii., page 129, ~i ves the history of the Inner Circle,

and considerations with regard to its electrification ; this article will be continued in the Decem her issue of TRACTION AND TRANSMISSION, which will also contain a full descrip­tion of the Sondrio-Lecco Railway.

TENDERS IN BELGIUM.-Contracts are being arranged by the administration of the Belgian St~be Ra.ilways for 180 locomotive tenders.

[Nov. 22, 1901.

THE BALANCING OF LOCOMOTIVES.* By Professor W. E. DALBY {Member), of London.

AR'!lOLE ~.-The object of this paper is primarily to explam.at;td Illustrate a ~onvenienb semi-graphical method of ?hbammg the m~gmbude a.~d .position of the balance ~etghts for locomottves, and m01dentally to discuss and illu.sbrate the d~fferenb ways of dealing with the reoipro­catmg masses m coupled engines, and to consider the effect of the balance weights on the permanent way and on the tractive effort of tlie engine. . Th~ ~vantag~ of the metliod to be explained is its

stmphctby,, and, m the case of engines in which the L. and R. cyhnder gear are alike and symmetrically disposed that it is self-checking. '

The dynamical principle on which the method depend3 has been previously fully described by the author t hub for the sake of completeness a brief explanation ~f the fundamental ideas involved will be given here.

The paper has been divided into nineteen sepuate Articles, as follows :

1. Object of the paper. 2. Principle of the method. 3. Definition of the reference plane. 4. Graphical representation of the centrifugal force

and couple on the reference plane. 5. Conditions of bal.a.nce. 6. Preliminary reductions. 7. Revolving and reciprocating masses. 8. Example 1: Inside cylinder single engine, 26 in.

stroke. 9. Example 2: Six-coupled goods engine, Lancs.shire

and Yorkshtre Railway. 10. Variation of rail pressure; hammer-blow. 11. Example 3. 12. Speed at which a wheellifbs. 13. Slipping. 14. Value of 'W ,· the resultant variation. 15. Example 4: Four-coupled bogie express passenger

engine, Lancashire and Yorkshire Railway. 16. Distribution of the reciprocating mass between the

coupled wheels. 17. American practice. 18. Example 5: Eight-coupled engine Class E, B~ld­

win Company. 19. Four-cylinder looomobive3. ARTICLE 2.-Priln{)iple of the Method.-The firsb point

to be clearly underabood is that the effect of a F orc3 F (Fig. 1), with reference boa point 0, whose perpendicular distance from the line of action ofF is a feet, is equal to-

1. An equal and parallel force to F, indicated by j, acting at 0.

2. A couple, whose m agnitude is Fa. The applica.bion of this principle t > the case of a revolv­

ing shaft acted upon by the centrifu~al force due to an attached non-axial mass is the key to the method. Con­sider Fig. 2, in which a shah 0 X carries a truly- turned

.1. Pu:,.J. (.

f •

• ------------- ,.. . """"' ·---------- -- ---

0

F

BB· z. REfERENCE

,.k-----, ' I ' I \

I \ r. I \ ~'f

! X I , I I I I I ,' I ; I I I I I I I ~

I I I 1------+-----!.. , "I 1--..L-. • r , I ' I I ' X I - ·- · t --J..-----+-1-·---i-' I

U.,...-T-1 - +Ji. ' I 1--...-.1;1 - , I I \ I I I 1 \ 1 I I I

\ 1) / 1 1 I ~\ 'I-I I I

1t

0 ' -+ \ I c.' <VI I I

\ ~0 I

r. \ ~· / ' 'Y ' , • ' \ ~' .... _... ... ' ,.

\ '-~

•

PLAN£. •

disc D, to which a mass M is attached. Let ?' be the distance of the mass centre of M from the axis of the shaft; then when the shaft turns at w radians per second, a. centrifugal force M w2 r = Facts upon the shaft. The effect of this force with reference to the point 0 , which may be taken anywhere, is-

1. An equal and parallel force M w~ r = F acting at 0. 2. A couple M w2 r a acting on the shaft tending to turn

* Pd.per read before the Institution of J\IIechanioal Engineers.

t "Balancing Engines," Insbitution of Naval Archi. teots, 1899, page 186.

•

Nov. 22, rgot.]

tl.t aboub 0, in the plane containing the axis of revolu­t ion 0 r , and the radius of the mass ~I. A couple of this kind is usually called a. " centrifugal couple, beca.use the forces forming it are centrifugal for ces.

In these expressions, and in all the expressions follow­ing, M or '1n is the ma~ mea.<Jured in J?OUnds, conse· quently the forces will be in ab10lube umt~, unless the expression be divided by g, in which c~se the forces are in pounds weight, the usu'l.l unit of force. In b~lancing problems bhe mass of the different parts is under con­siderd.tion, and the question of force is nob immediately conce rned, so thab the form~ M w2 r, &o., are more

. h M w2r . oonvemenb to use t an , or the equiValent form g

~ w2 r. Hence M is alwaya to b3 interpreted mass g d. measure m pounda or to:u. a3 the ca<Je may be.

ARTICLE 3.-Reje?·ence P lane (F1g. 2).- A plane ab right angles to the axis of revolution containing the potnt 0 is the plane _in which the transferred force aobs, and for convemence 1s c~lled a. reference plane. Both the refdrenoe plane a.nd the plane in which the centrifugal couple aob~, rotate as bhou~h fixed to and forming part of the rubabing system. The reference plane i~ besb thought of as a. drawing-board keyed bo the shaft ab 0, and therefore rotatin~ with ib. Ib is on this ideal draw­ing-board thab the bJ.la.ncing is worked oub.

AUTICfJ& 4. -Graphical R epresentation of the CentrifuJal Force an!t Couple on. the R eference P lane.- The tuns­ferred force acting a.b 0 may be represented by a line, 0 F in Fig. 2, drawn to scale in the reference plane. It must be drawn Mw2r units long, and parallel to the radius of M.

The couple may similarly (as shown in Fig. 2) be re­prdSented by its axis, but for the purpose in hand ib is sufficient to represenb ib b7 a line drawn on the r eference plane parallel to the radtus of the m'l.S~, M w2 1· a units long.

The direction in which the3e line3 are drawn must be carefully attended bo. The line representing the force must always be drawn in a direcbion from bhe point 0 oubword~. If the line representing the couple is drawn from the p)in~ 0 oubward3 and parallel to the radius when the mass is to the right of the reference plane, ib must be drawn radially towards 0 for a mass on the lefb of the plane, since the two masses tend to burn the system in opposibe directions.

ARTICLE 5.-Condtitions of Balance.- If there are several ma.-3ses attached to and revolving with the same sha.fb, the centrifugal force due to eaoh is to be treated in the same manner-that is bo say, a reference plane is to be chosen and e1ch force separately referred to it, giving a. system of forces a oting ab 0, and a system of couples. The tota.l unbs.lanced effect of the m'l.sses will b s represented by:

1. The resulbanb of bhe transferred faradS aobing ab 0. 2. The resultant of bhe couples.

T he conditions of balance for a system of 1·evolving 1n({,Sses are evidently bha.b, when the proce33 of transference has been carried oub with respect bo any reference plane :

1. There shall be no resultant force-i.e., the force polygon in the reference plane must close.

2. There shall bs no resultant couple-i .e., bhe couple polygon must clo3e.

ARTICLE 6. - Preli minary R eduction.-In drawing the lines representin~ bhe forces and couples they may be made proportional bo Mr and Mar simply, because the w·!, being the same for every mass in the system, and being C)mmon to any applied balance weights, may for the time bein~ be considered equal bo unity, ab the end of bhe problem, 1f bhe actual magnibude of the resultant force, or resultant couple is required, the proper value of w2

must ba Msociabed with the line represenbmg the resulba.nb foroe or coup1e, found by measurement from the force or couple polygons.

Ib should be noticed that if the force and couple poly­gons for a given system respectively close, the system is in ba.la.nce for a.ll spefds. So far then a.s the speed is concerned, in finding the b~lance-weighbs w may always b3 written equal to unity. A further simplification is made in the work by first reducing all the m9.5Ses bo crank radius. Then the radius cancels oub and the sides of the force polygon are drawn proportional to the respective masses at crank radius, and the sides of the couple poly· gon proportional bo th~::SSe masses respectively multiplied by their distances from bhe reference plane.

To find the a.obual force or couple in this latter case bhe lengbh of the line representin~ either of them must be multiplied by w2 r, where r 18 the common radius to which all the masses are supposed reduced. By making the assumption bhab w2 <r = unity:

1. The ma~ ab crank radius is the centrifugal force in absolute units.

2. The mass ab crank radius multiplied by its distance from the reference plane is the centrifugal couple in abso­lute units.

This assumption will be made throughout, so that, insbead of mo.~ and ma.s3 moment, the terms centrifugal force and centrifugal couple may be used.

AR'J.liCLE 7.-Revolving and R eciprocating Masses.-The moving masses in an engine may be divided into those which revolve with the crankshaft, and those which the crankshaft reciprocates. The preceding principles apply­ing to revolving mass, may be made to a.pply to the re­oiprocabing masses. It is only necessary to suppose that the reciprocating masses are transferred to their respecbi ve crankpins and to brea.b them there a.s a sepa.rabe revolving ~Jystem, the balance weights found being those which, when reciprocated, will balance the reciprooatin~ masses. This method of treatment really assumes a.n infi01tely long Clnnecbing-rod, so thab the solution obtained for ordinary rods is only approximate. The error involved is, however, negligible in locomotive work. Again, in locomotive

E N G I N E E R I N G. work ib is almost the uni veraal custom bo balance bhe re­oiprooabing ma~es by revolving mas 3es placed in the wheels, the o.obual b'ltlance weight in a wheel being the resulba.nt of the b~lanoe weights required for the revolving and reoiproca.bing parts respectively. There is therefore no need to discriminate between the revolving a.nd re­ciprocating pa.rts in the process of finding the balance weights. Having settled how muoh of the reciprocating pa.rt3 itJ is desirable bo balance, include ib with the ravolv­mg masses at the ora.nkpio, and consider the whole as a. revolving sys tem.

The method adopted in the following examples is to bake a seb of reciprocating parts and to balance them con· sidered a.~ belonging respecbi vely: bo an inside cylinder sins-le engine, and a. 6-coupled instde engine. The reoipro­oatmg p~rb3, dimensions, and revolving pa.rts whera po3-sible are bhns3 common to a. large number of the L anca­shire and Yorkshire 4-coupled and 6-coupled engines, the da~a. of which has kindly been supplied by Mr. Aspinall. F ollowing a. UAual cusbom, bwo-thtrds of the reciprocating masses are balanced in each case.

E XAMPfJE ].

A RTIOLE 8.-Z:nside Oylin,dcr Single En.ginc, 26 i n. Stroke: Data.

Distance centre to centre of cylindera Dista.ncs between the planes contain­

ing the n1as 3 centres of the balance weights . . . . . . . . . . ..

M~s of unbalanced revolving part~ per crankpin reduc3d to 13-in. radius . . . . . . . . . . . . . ..

Ma.<38 of reciprocating parts per cylinder ab crankpin radius ...

Proportion of reciproca.bing parts to be balanced . . . .. . .. . . ..

The mass bo be balanced a.b each crankpin is therefore 6H + ~ of 551 lb. = 10lllb.

1 ft. 11 in.

4 ,, 11 , •

644 lb.

551 ,

two-thirds.

Draw the plan and elevation of the ora.nk axle as shown in Figs. 3 a.nd 4, so that in elevation bhe L. driving wheel shows to the front. Choose a rf ference plane to coincide with the ~;>lane containing the ma3s centre of the R. balance wetghb and mark on the plan bhe three dimen­sions i j k. Ib will be found couvenient to a.rrang(! the data. in the war illustrated in the folio win~ Schedule No. 1. The numbers 10 italics are those whioh have to be found.

ScHEDULE No. 1. Inside Cylinder Single Eng ioE'. R eference plane at No. 1,

plane, Fig. 4.

No. of Oran lr.

-- -w. No. 1 R. h \lo.nce wt . . . No. 2 R. orank . . No. 3 L. orank . . No. 4 L. b~lance wt .. .

Distance Equ ivalent ~lass Equivalent. from at Orauk ~hdius &lass Mo.ment

reference = Oentr1fu~al = Oen t.r1fugal

Plane Force when Oou ple when

• w2 r = 1. w 2 r = 1.

X. 0 in

18 in. 41 in. 59 in.

Y. 76G

l Oll l Oll

766

- -

z. 18 .198 M,Mil M>,.UO

Consider the R . Crank.- ItJ is 18 in. from the refer­ence plane. The centrifugal force, w2r being unity, acting on bhe a.xle due to the 101llb. ab the R. crankpin is 1011 absolute units, acting always along the crank radius out· ward from the centra. '£ra.nsferred to the reference plane, this is equivalent to an equal and parallel force acting ab 0, and a couple whose moment is represented by the product 1011 x 18 = 18,198. The effect of the 1011lb. a.b bhe L. crankpin, with respect to bhe reference plane, is similar bo a force at 0 represented by 1011 and a couple repre3ented by the product 1011 x 41 = 41,451. To see wha.b bhs resultant effect of these two couples is, and what mass must be added to balance them, choose any convenient scale and draw A B (Fig. 5) parallel to the L. crank and 41,451 unibs long to any convenient scale, a.nd B C parallel to the R. crank 18,198 units long. A C represents bhe toba.l burning effect, and there­fore C A represents bhe moment of bhe couple which will effect balance. This line scales 45,200 units, and there­fore the b1.la.ncing mass musb be of such magnitude, M, and placed ab such diabo.nce a from the reference plane that

M a-= 45,220;

and, moreover, M must be placed ab crank radius in the relabi ve angular position to the cranks given by C A (nob A C). This line 0 A is oa.lled a. closure, since ib is the line which closes the couple polygon, giving at once the direction and magnitude of the balancing couple.

The angular oosition of the balance weight in bhe L. wheel is therefore given by simply drawing _ a line Q Q (Fig. 3) parallel to C A. Its magnitude M. o.b crank radius, is found from the above product by dividing bbe 45,220 by 59 in., nhe distance a.b which the balance weight is to revolve from the reference plane, giving 766 lb. The three masses-vi~ .• 1011 lb. ab the L. and R. crankpins respectively, and 766 lb. in bhe L. wheel-have now no tendency to turn the system about 0 ab all. There is still left, however, the transferred equal and parallel forces due to these three masses acting ao 0 . To find the resulba.nb of bhesP, choose a. suitable scale, which will in general differ from the scale used to draw bhe couple p Jlygon, and set out Fig. 5, Ab o d respectively equal and parallel bo these forces-i.e.:

A b parallel bo the L . crank 1011 units long. b o , , R. , , od ,, , L. bl.la.nce weight radius C A, 766

units long.

A d represents the resultant, and therefore d A the force which will balance the system. This must be sup­plied by a. mass revolving with the reference t>l~ne-tbab 1s, in the righo-ha.nd wheel. The angular pos1t1on of the R . balance weight is given by drawing a line parallel to d A from tho centre of the axle. The magnitude ~~I is given by the lenR"bh of d A. Thii measures 766 units. M is therefore 766 I b.

The check on the accuracy of the work lies in the facb bhab if the masses ab the R. and L. crankpins are equal, a.nd thab if their planes of revolution and the planes in whbh the balance weights are placed are symmetrically disposed with regard to bhe central vertical plane of the engine, the two balance weighbs must be equal in ma~ni­tude, and their angular positions must be symmetnca.l with re3peob to the cranks. One balance weight is found from the couple triangle A B C, Fig. 5; the other is therefore known ab once, and the dra wing of the force polfgon A b c if, is therefore really unnecessary, bhoue-h md1spensable a.s a check, since d A should scale 1ts

Pt:J 3.

:I¥J.4.

N'2.

•

I I

Q) ... • ~

I 1/l.hs.- ~ ,..L-4-

·---'-

•

I

I I I I I

• ... ~

I ·~ I I I I I I

-*.

.... 4 cr=========L~=====:;> •

ll{]· 5.

oB

• ~ • ~

I I I I 1 I I I I I I I I I I

already-known magnitude, and should be inclined to the R. crank at the same a.ngle that CA is inclined to tha L. crank. A consideration of the above method will show that the artifice consists in choosing the reference plane to coincide with the plane of rsvolution of one of the unknown balance weights. Whatever be its mass, it has no moment with respect to 0, and can form no centrifu~al couple acbing on the sysbem; balance amongst the couples due bo tihe remainin~ three masses ca.n then be effected, leaving the mass m reference plane to be adjusted bo balance the forces transferred to 0.

'£he method of finding the balance weights may be shortly summarised as follows :

1. Draw a plan and elevation of the axle; mark on the necessary dimensions from the reference plane taken o.b the centre mass of the R. balance weight .

2. Fill in a. schedule like Schedule No. 1 (above). Multiply the figures on the Sill me level in columns X and Y together, placing bhe products in column Z.

3. Set oub the products in column Z as if to form a polygon ; remembering the instructions of Article 4 : the direotJion of each produob is defined by the corresponding crank given in column W. The line necessary bo close the polygon defines bhe angular position of bbe balancing produot-i.e., of the balance weigh b. Transfer this direc­tion bo the elevation of bhe crank axle. Measure its length and divide it by the quantity k. The quotient is bhe magnitude of the balance weight ab crank radius.

4. Sat onb the quantities in column Y as if to form a polygon. The closing sidE', taken in order with the rest defines the angular position and magnitude of the balanc~ weight in the reference plane. For symmetrical engines this checks the work in the way already explained.

The actual mas3, M 1 of the balance weight, depends

•

of oou~se, upon the distance R of its mass centre G from the aX\8,

If.'~' is nhe crank radiu~, M 1 is found from M 1 R = M 1'

= ~66r for Example 1. Taking r = 13 in., and R = 36 in., wh1ch . would be about the practicab!e distance for a '!-ft . 3-m. wheel, M 1 = 276lb. This should be arranged m crescent form between the spokes, as shown in Fig. 3 (page 727).

E XAMPLE 2. AUTIOLE 9.-Six-Coupled Goods Engine, 18-In. x 26-In.

Cgli~n.fters, Lancas_h~re and . Yorkshire Railway. - A drawmg o~ th~ dnvm~ axle IS shown in Figs. 6 and 7. There are m t~1s case e1ght _masses revolving in the eight planes sh~wn m the plan (Ftg. 7). The new feature in this exa~~le IS the coupling rod. Each coup1in~-rod is to be dt vtqed between the three outside crankpms in the proportiOn that they respectively support of its weight. In the present example the leading and trailing wheels each take 143lb. per crankpin. the driving wheel257 lb. The total mass of each rod is 543 lb. The proportion may

' I ~ ()),

F0· '1. - ------""'"-;..1--- ·,-""---.- - - -.- N'! 1.

-· .. _ .. 2. .. a.

Ref.P~

N !'5.

1,~

•

c- b C B D

/1114 Cl

be arriv£d at expeditiously by l>laoing the rod on three knife-edges ab the three centrelin~, each knife-edge being suitably supported in the platform of an independent weighing machine. The readings of the three scales give the proportions ab the respective crankpins.

In general, the common radius of the outside cranks of a coupled engine is less than that of the inner cranks. The masses forming the system about the driving axle must be reduced to a common radius. Generally the radiu~ of the inside cranks is used.

Dnving Wheel. F or each outside d riving crankpin:

Proportion of coupling-rod ... ... Outside part of crankpin and washer

lb. 2571 25 f

Total . .. ... ... 282 Equivalent to 217 lb. at 13 in. radius.

ab 10 in.

The connecting-rod is the same as in the previous ex­amples. The usual practice in E ngland is to balance the propo~tion of ~h~ reciprocating _masses dec~ded upon e~­tirely m the dnvmg wheel. ThiS method IS followed m t he present case.

Collecting the data for the driving wheel : Data.

Distance centre to centre of cylinder 1 fb. 11 in. Distance centre to centre of coup-

ling-rods . .. .. . .. . . . . 6 , 1~ , Distance between planes 2 and 7

con t&ining mass cen bres of wheel cranks . .. .. . .. . .. . . . . 5 , 1~ ,

•

E N G I N E E R I N G. Distance between planes 3 and 6

containing mass centres of balance weights ... ... . . . .. . 4 ft. 11 in.

U nb&.lanced mass ab each outside crankpin in planes 1 and 8 re· duced to 13 in. .. . .. . . .. 217 lb.

Unbalanced mass of wheel cranks and part of pin in them reduced to 13 in. radius revolving in planes 2 and 6 U6,

Un~~lanc~d ~ass of re~olving parts a each ms1de crank pm . . . . . . 644 , , M~~s of reciprocating parts per cy.

lmder .. . .. . . .. . .. .. . 551 , Mass revolving at each inside crank

journal in planes 4 and 5 is : Revolving... . .. .. . 644 Two-thirds reciprocating 367

--Total .. . ... lOll

Fill in Schedule 2 for the driving wheel, and compute column Z.

SoHEour ... E 2. Six-Coupled Inside Cylinder Engine : Driving WheeL- Crank Radius = 13 in. l~efereoce P lane at No. 3.

-----------------....,-------

Number of Crank.

mstance from Reference

Plane.

Equivalent Mass Equivalent Mass \ t Crank Radius Moment = Oen­= Centrifugal t rifugnl Couple For~e wbere where

w2 r = 1. w2 ,. = 1.

w. X. Y. z. Jnch~>P.

No. 1 - 7 2 2 l7 - 1,562 , 2 - 1.4 96 - 13r1 , 3 0 494 0 , 4 18 lOll 18,198 , 5 41 1011 41,451 , 6 59 494 29,140 , 7 60.4 96 5,798 , 8 66.2 217 14,365

Draw the couole polygon, Fig. 8, A B, B C, C D, DE, E F , F G, to scale, baking the magnibudes from column Z. Notice that C D returns over A B and BC, and that E F, F G are drawn in a direction from their crankpins to the axis, since the planes in which the corresponding masses revolve are on the opposite side of the reference plane to the other masses (see A rt. 4). The closure G A measures 29,140, and it fixes the direction of the balance weight in plane 6-i.e., in the L. wheel. Dividing by 59, the quotient 494 is the magnitude of the balance wei~ht. Check the work by drawing the force polygon. F1g. 8, A b, b c, o d, de, e j . f g, g h. The closure hA ~ives the direc~ion of the R. wejgbt, and it should 6cale 494 lb., thereby checking the work. R e­member that for the force polygon the direction of drawing is always from the axis parallel to the radius towards the crankpin (see Art. 4).

L eading Wheel.-The unbalanced masses are wholly revolving and should therefore be entirely balanced. They consist of the urankarm, crankpin, and a proportion of the eoupling-rod. They revolve in different planes, form­ing a system of six masses revolving in six different planee-, which are t abulated in Schedule 3, column X, rela­tively to the reference plane. An elevation of the lead­ing wheel is shown in Fig. !l.

•

I i 1-a: :Ft{j. 10. L~ s.1iwJ.uyJ TV/~.

rr------!

} .B v . , A

,,, . 0} Clo.nu-~

Additional Data.

1-Iass due to couphng-rod Mass due to part of pin

washer outside crankarm

lb. . .. 143

and .. . 25

.c D

E

168 at 10 in. radius. Mass of wheel crank and the

part of the crankpin in the wheel . .. ... .. . . ..

Fill these mass€s in Schedule 3. 125 10 , ,

L Nov. 2 2 , rgor. S CHEDULE 3.

Six:Coupled Inside Cylinder Engin('. Leadmg Wheels. Crank radius = 10 in.

------- -Equivnl('nt I Equh·aJeo t.

Number ot Crank.

Distance from Reference

Plane.

Mass at Oraok Mass Moment. = R1dius = Cen - Cent.rifu~ral t rifugal Force Couple wben

w = l. w=J.

w. X. Y. z. I nches.

No. 1 - 7.2 168 - ] ,'~09 H 2 - 1.4 125 - 176 , 3 0 317 0 , 4 fi9 317 18,720 , 6 OO.t 126 7,550 , 6 66.2 168 11,122 • •

- -The couple and f?rcA _pol_ygons Oorre~ponding to the

schedule are. drawn m F 1g. 10, and the balance weights they de.ter~me are shown, the L. one full, and the R. one dotted m F1g. 9.

T he balamcing of the trailing 1vheel is the same as for the leadin~ wheel. in every respect.

The radn ab wh10h the actual balance weights were pub are :

Fb. In. Driving wheel .. . .. . .. . .. . 1 10 Leading , .. . . .. .. . .. . 1 10 Trailing , .. . . . . . .. . . . 1 10

Therefore the mas~es of the actual weights are:

Driving wheel = 494 x_ 13 = 292 lb. 22

Leading = 3l7 x 10 = 133 ., 22 ,

Trailin~ ,, = 317 X 10 = 138 " 22

The angles, measured from the drawiue-s of the poly-gons, which the L. weights .make with hor1zonbal are :

Driving wheel 43 deg. below centre line . L eading ,, 4 ,, , , Trailing ,. 4 , " ,

. Thelelt-hand side of the engine id Lhown in Fjg. 17 (to be g1 ven la ter), the cranks being placed in their proper relation to one another, and the balance weights shown in bla.ck.

In ~h~s type of engine b~e distance between the planes contammg the balance wetghts and those containing the wheel cranks is so nearly the same that practically they may be treated as coincident. In the previou3 example t?e two planes have been retained in their exact posi­t iOns for the sake of generality. The example then forms a. type for coupled engines with double frames and over­hung crankarms.

A four-coupled inside cylinder engine is worked out in the same way as in the previous example.

(To be continued. )

DARLINGTON TRAMWAYS.-The Tramways Committee of the Darlington Town Council have arran~ed to seek powers to borrow l OO,OOOl. for the const ruction of a new tramway.

SouTH AFRICAN GoLo-:NIINING. - Although crushing has been resumed in the ~ransvaal, it _appoars very doubtful whether the extractiOn effected th1s year will be equal to thab of 1900. In January, February, and March 1900, as well as in November and December, 1899, th~ Boer Government worked the Witwatersrand mines with a certain vigour, the extraction for the first quarter of 1900 being 251,677 oz. Nothing was done in the way of working the mines between 1\farcb, 1900, and 1'Ia.y, 1901. In the lat ter month a few mines were started by British managers, and the number of mines in working has since been gradually increased, so that while the out­pub of May was 7478 oz., the production of October was 33,393 oz. The extraction for the six months ending October 31 was 147,019 oz. But even if the output in November and December amounts to 40,000 oz. per month, the yield for the whole year will still be somewhat below the irregular produqtion of 1900 . There is, however, every probability that production will be carried on with a gradually increasing vigour in 1902. Although the working of the mines by the Boer Govern­ment in November and December, 1899, and January, February, and March, 1900, was really carried on with a view to give the Boar Government immediate funds, without any regard being pa.id to the rights of the com­panies owning the mines which were brou~ht into activity, the general result was probably favourable from the owner's point of view. The Boer Government had entire control of the mining interests of the J ohannesbnrg dis­trict for the five months in question, and inflicted no damage upon the mines. as ib r('garded them as a valuable aeseb from which to derive the sinews of war. At the close of the first quarter of 1900, the authority of the Boers was so weakened that they derived no f urtber profit from the mines, and ab the same time their power for working mischief was ab an end. The progress of gold-mining in R hodesia has scarcely realised the expec­tations formed respecting it. Still, the output of Rhodesian gold for the fus t ten months of this year was 140,506 oz., as compared with 91,850 o~. for the whole of 1900, 62,313 or.. for the whole of 1899, and 18,085 oz. for the whole of 1898. ' Vhen the returns for November and December are brou~hb in, ib will probably be found thab this year's Rhodes1an produotion will range between 165,000 oz. and 175,000 oz. The combined output of go'd in the Transvaal and Rhodesia this year appeard likely to be nearly 400,000 oz. , of the value of 1,500,000l. in round figun s.

•

Nov. .,., --, 190!.]

"ENGINEERING" ILLUSTRATED PATENT RECORD.

COMPIT.ED DY w. LLOYD WISE. BEI·ECTED ABSTRACTS OF RECENT PUBLISHED BPBCIFIOATIONS

UNDER THE ACTS OF 1883-1888 T~ mnnber oj views given in the Specification. Dr~uri s i8 t ted

!::,t e:Ji':r~t~::::J. where none are mentioned, the sp:Jjlcat~o':1 is

Where inventi0?18 are communicated from abroad the N d:~··. of the C~mm'!'nicators are given in t'-tali~. ' anus,

Copteg of Specijlcattons may be obtained at the Patent Office s l Bt,rancl~, t6, So~tthampton Buildings, ChamcenJ·lane lf. c a a~ ,~,e tmt/ orm. pn.ce of 8d. ' · ·'

The d~te 0.~ th~ a!'lvertisement of the acceptance of a Com lete 'Jfctfit1ttw 1b ts, tn each case, given after the abstract tmles~ the . a en as een sealed, tuhen the date of sealing is o'iven

~ 11f p:dson '!lav, at a'll1J tim e within two m011.ths from the date of t !e v~ttsement of the accepta·nce of a Compl~te Specification gu;e 11ottce at the Pate11t Office of opposition to the r nt .r ' Patent 01~ any of the grounds mentioned in the .Acts. g a

0J a

AGRICULTURAL APPLIANCES.

21,019. J . . E. Rausome, Ipswich. Short-Grass Cutter. [5 Frys. J November 2l, 1900.- ln order that the <·~t grass may not c log t.be kni\'CS or be thrown in improper direc­tiOns a c~ncave deflector is fitted behind the knh·e~ . and the top

Fig.2.

-- . =~

-

~s.----------·

I

• I • I • I

·--·-·­·- ·-·

of th e graf s box i::t broug h t o ,·er t.he deflector in such a manner ~bat ic; ser ves to r eceive the g rass from t he knives and direct it l!lto t~e box. A clearer for t h e g rass box comprises n t ravel hng diaphragm moved by chain gear, put in motion by a hand­wheel. (il ccepted September 25, 1901.)

21,751. A. Shuttleworth and R. Gamble, Lincoln. Threshing Machines. [6 F igs.] November 30, 1900.- Tbis invention has reference to t hreshing machines of the kind in which the threshin~ d rum is provided wit.h ribbed beaters, and there is aw~n~ed half round its periphery or thereabout a compound" con· cave" provided with cross bars, a narrow space being ltft. between t be drum and the concave through which t he unthresh(d corn is drawn by the rapid ro tation of the drum so that the g rain becomes St>parated from the straw by the friction between the bentera of the d rum and the c ross bars of th e concave. As is well known, the friot.ion r eferred to in ooune of time wears away t he upper edgfs of the cro~sbars of the concave, thus rendering them blunt and impairing the efficiency of the threshing. To obviate the necessity, wh ich formerly obtained, for taking the concaves to pieces and r e-inRerLing the c rossbars in t h e heads in r eversed position in order that their worn edges should be underneath and th eir sharp edges uppermost, compound concaves such as de· scribed have been made with bot.h ends of the beads of the upper part alike, and of such form tbat t he position of t he upper par t c1n be reversed whenever the upper edges of t h e c rossbars have

Fig. f. 2.

E N G I N E E R I N G.

ELECTRICAL APPARATUS.

2~! 700. J. B. Langford, London. Cable Connectors (·1 P t~B. ] Decembe.r 28, 1{)00.-:This invention relates to termiuo.ls; coupliog.il, or j unct10ns for a w1re or for stranded electric ca bltP or the .hke, and according thereto a pin with a t.hread cut o~ one o~ tts ends has on the other end a smoot.b r.oned point, and screw10g on to this t h read and over the coned end icJ a bend o r nut. The upper part of the inside of this head is coned to fit rnrnllel to the surface of ~he cone. on t.he pin, and a hole is out through the top of the sntd head m order to allow the wire or

wi res to be pushed through. The outside of t he bead may be shaped so as to be easily screwed up by band. lu use the wires nra J?UShed thr_ough the hole in the bead and spread out on meet1~~ t~e po10t of . the cone. On screwing up the connector eao~ "!re 1s firmly ~rtpped between the surface of the cone and t he _lDBtd~ of the bead or nut, thus making good elect rical contact. Vart_ous smgle and double forms of such a connector a re described and Illustrated, and are dnimed broad ly and in detail. (Accepted October 2, 1901.) •

17,024. The British Thomson-Bouston Company Limited. ( W. C .. Fibh, Lynn , .Mass., U.S . .A.) Insulating Mate.r~als. [6 ! 'l{JR.] August 24, 1901.- Insulntiog material compn smg carbomenble subst.ance, is according to this inventio~ made from layers of asbestos poper or the like with small b roken

•

( ,,,~# )

or powdered mica between, t.he whole being caused to adhere togethEr by being mixed with va rnish and subjected to preesure while hot. Assembling frames and a p ressing device, by means of which the nontents of a number of frames can be pressed at one lime, a re described and illustrated. (Accepted October 2, 1901.)

17,029. The British Thomson-Bouston Company, Li.mited. (H. R. S arne?tt Scltenectady , .N.Y. , U.S.ii.) Lightning Arresters. [1 Fig.] August 24, 1901.-A device nppliclble for breaking arcs which may have been started by light· mog between conductors conveying high-tension c urrent o f g r eat enerf!Y according to this invention comprises means for causing a sumcient r esistance t o be automatically introducP.d in to the diecharge path by t he current passing tl.&eretbrougb in order to prevent the maintenance of an a rc at the nor mal potential of the mains . An apparatus is described which comprises a series of

~ecome blunted tbro~gh w~ar. In n threshing machine accord· 1

metallic buttons with air gaps between, constituting t he safet.y mg to t.he present mventton both t he. upper and the lower d ischarge path, and to a contiguous pair of its buttons is connected parts of t.be concave a re m.nde r~verstble , both ends of the (in shunt to t he a ir gap) an elect ro-mag netic de vice adapted on beads of the upper part ~etnJ! ahk~, and both ends o f the t he passage of current to open a sbor t·circuitswitob on a carbon rod heads of the lower part be10g also ahk~. The two par ts of t.he resistance connected in series with the safety discharge path. The coocaye a re jointed toget~er by a rod wbtch passes t~rougb round p roprietors of t he patent, eay: " We consider ourselvea the first to holes tn the adjacent portto~s of the beads of . the satd two pa~ts, conceive the idea of automatically inserting a resistance in series tbe. ends of the rod p rojecting through. the Btde.s of t he machme with contacts between wbiob au a rc ruay bts formed, in order to wbtl~ supported on the frame, means bemg prov1ded for adjusting break the arc, and that we a re the fi rst to c onceive the idea of the dtstance of the concave from t he drum ~e~ters. The top nod npply iog this conception to a lightning arrester for high-potential the bottom of the ~ompound concave ar~ stmtlarly suppor ted. by cn cuits." (Accepted October 2 1901.) o ther two rods wbtcb pass through slots 10 the beads and a re hke· ' wise provided witb means for ad justing the distance of the con- 17 .• 490. B. Kuettner, Lon~on. ~t.orag~ Batteries. r a ve from the d rum l•eaters, the slots being made oblong t.o allow [3 l1'1gs. ) Oo.t.ober 2, 1900.-Accordmtr to t.hts mvent.ton spc_:mgy lend or the said adjustment.. The vacant spaces which would other· and le!ld o~tde el~ctrodes nre .hnrdened by menns of s thoa. T~e \\ise be left between the outer sides of the upper part of the con- paste 1s m1xed .w•th sol~tble stlicnte, and tl.te pasted electrode .ui Cl\'e and the machine sides a re provided with filling pieces, whereby lmmer~ed firs~ ·~ very dtlute alkaline solutton, nod .~fterwards m straw is pre,•ented from accumulating between the heads of the a solut10n o~ stmt lar c bara.oter, b~t strong~r. The ~1hcate may be upper portion of the concave and the machine frame the said that of sodiUm, and t he tmmerbtOn nlkahne solut10n may be of filling pieces being provided wiLh dowels or projections ' which ftt I ammonium sulphate .. It is stated that "forming" of s~ch plates into corresponding h?les in t he said beads. (Accepted September proceeds from the J:r rtd outwards, and .that the peroxtde plates 25, 1901.) should be " formed" in the usual solut.1on, but the spongy lead

•

pla~es in a solution of ammonium sulphate. It. is state d that the ncttve matter t reated as d escribed is liable to very slig h t expan· sion and contraction in use. The g rid used to support and con· neot the act.ive matter is preferably of the kind illustrated. The first claim is as follows: " In a method of mixing secondary

0

•

bnttery plates mixing lend oxide (with or without t.he addition of finely-divided lend) with a solution of a soluble silicate to form a p~te, maki.ng the ~aste into a plate and dipping the plate into a dllute alkahne soluttoo, substantially as herein described." (.Ac· cepted October 2, 1901.)

21,233. J. Pescatore, Manchester, and The Tudor Accumulator Company, Limited, London. Storage Batteries. [4 Fig~.] Nove~b~r 23, 1.000.-A fo~m of storage battery plate accordmg to th1s mvent10n compn ses two thin plates made fr<;>m pe~forated g riJs whose perforations have heen wholly filled wtth act1ve matter , t he t.wo t hin plates thus consti·

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tuted being made up together to form a single plate in such manner that there is a sufficient space between them to allow acid to percolate to the interior parts of t be active material. A double electrode &eotion may comprise " neJ,tative" spongy lead plates made according to the invention, and ordinary peroxide plates for "positives." (Accepted October 2, 1901.)

14,841. J. T. Armstrong and A. Orling. London. Wireless Telegraphy. [8 .Figs.] Aug udt 18, 1900.-Wire· less telegraph apparatus specially designed for use in controlling tor pedo r udders, and with tbe object of eliminating secondary disturbances which would affect t he cober er, in one arrangement according to this invention comprises : In electro-magnetic wave· r eceivin't apparatus, a normally closed eleotric circuit having a

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coberer, a battery, and a sensitive relay ndapt.ed to control a re1ay circuit p rovided with a batliery and an electro·magnet whose nrmn.ture carries a detent which on being attracted is withd rawn from its nor mal position of engagement with a ratobet wheel mounted on the shaft of a motor, thus permitting it to l'Ot.ate, a b reak wheel forming p:Lrt of either or both the receiving and relay circuits, which is or are thereby opened and the detent permitted

•

730 to return to its normal position, to enga~e the next tooth of t.be ratchet wheel, and thus atop the motor , by wbioh a t rip hammer or equivalent device is a lso opt>rated and decohesion Effected. (Accepted Septembt:r 25, 1901.)

GAS ENGINES. PRODUCERS, HOLDERS, &c.

16.619. J. G. Bormann, Berlin. Gas and Vapour Engines. f2 Figs.) September 18, 1900.-A gas engine ac­cordin~r to t his invention has no water·cooling device for t he C.} Jinder, but in one arrangement the cylinder and piston a re

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organiafd so as to be double-acting , gas exploding on one side of the piston and volatile liquid being evaporated (nod serving to produce power) on the other, such volatile liquid being chosen as will sufficiently reduce t he temperature of the cylinder walls. (Acupted September 26, 1901.)

21,622. A. J. Boult, LondoD. (The New P rocess L ight­ing Company, Cleveland, Ohio, U.S . .A .) Gas Burners. [6 Fu;s.] November 29, 190:>. - The fi rst claim in this specification is broad ly : "In a lamp haviog an illuminating burner, tbe em­ployment of a caloric en~ine which converts a portion of the w~te heat into meohamcal power (as distinguished from a de,·ice driven by t he upward current of ai r caused by the flame or beat from the burner, or a device for separating bented gas or

nir from cooler fluid, and rei.} iog on its t emperature to supply the pressure), and mechanism operated by such power of the engine for increasing the supply of combustion supporter to t he huroer substantially a.a herein set forth." Means are provided for star ting the engine, t hese comprising a Bunsen buruer and by-pass and a mechanical star ting device. The apparatus works by pumping air into the gas pipe, and controlling apparatus for use with such a system is described. (Accepted Septernber 25, 1901.)

GUNS AND EXPLOSIVES.

22,369. A. Reichwald, London. (Fried. Krvpo, Essen, Germany.) Gun-Sights. [7 Figs.] December , 1900.- Ac­cording to this invention n. ~n-sigbt _compr!st>s a ~r<;>ss-wire telescope mounted upon a carr1er prov1ded w1tb a apmt-le,·d.

1.

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Tbe attachment is prefera.bly mounted on t he gun in such manner tha~ ita axis of rotation passes through its centre of g ravity, in rrder that t he adjust ing mechanism of t be level may be reli eved from the effects of u mnsa pressure set up by the flring or t he moving about of the g un." (.Accepted Septembe1· 26, 1901).

RAILWAYS AND TRAMWAYS.

7758. Burst, Nelson, and Co., J.tmited, and A. C. Nelson, Motherwell, Lanark. ValveforSandBoxes. [2 F(7B.) April16, 1901.-Tbia invention relates to valves of sand

E N G I N E E R I N G. boxes for railway or tramway vehicles, and it has fo r its object to provirte a valve through which t·he sand will flow freely, and not be liable to choke on account of the diminished sectional area oft he body of aaud. The valve casinlr with its upper par t is made in t he form of a hopper to contain the sand, and the sides are flan~f'd so that it can be secured to t he oar , an intermediate neck uniting the hopper to a abort coupling-pipe. The valve i~elf, which is of the cylindrical or conical plug type, is fitted in the aforementioned neck, and has a small upper port nod a larger one on the under side, so t hat when the valve is open sand will flow downwards by the action of g ravity from the hopper t hrough t he valve to the coup·

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ling pipe, which is preferably screw-threaded for the attachment of a pipe for di~tributing the sand on the rails. The opening at the bottom or lower part. of the p lug or key is so desi~ned that when t he supply of sand is cut off the plug or key will automatically empty itself. A number of prongs or spikes are fixed in the upper side of the cylindrical plug alon~side the port and project into the hopper , to serve the double purpose of breaking up the sand when the valve is turned from its closed posit ion to its open position by means of a lever outside the casing, and of limiting the movement of t he valve por t to that necessary to enable it to pass from t he open to the closed position. tA.ccepted Sep· tember 25, 1901.)

STEAM ENGINES, BOILERS, EVAPORATORS, &c.

23,821. J. Hopktnson, J. Lowis, and J. Hopktnson and Co., Limited, Huddersfield. Stop· Valves. [1 Fig. ] December 20, 1900.-A screw-down stop-vah•e according to this invention has the valve proper borne upon a part provided

with n screw of such coarse pitch that while the valve i:J free t.o rise and fall upon the same, yet chat~erinK o( t.be valve uoder con· dit.ions of unstable eQuilibrium is prevented. The part bearing t he valve is conveniently a block free t o turn on the end of the screw-down spindle. (Accepted Octobe1· 2, 1901.)

20,553. La Societe Soltgnac, Grille et Cie., Parts. Steam Generator. [2 Figs. ] November 14, 1900.- (0on,·en· tion date August 1~, 1900.) Io t his boiler:::> fork-shaped tubes at their lower ends take water from and at tbeir upper ends dis­charge steam and water into a water and steam drum situated bet ween t he ends of t heir legs. The entrances to t he t ubes may be constricted by tuyeres or by other means. There is one claim, as follows : .. A system of steam generator consisting of a water-feed drum sen •ing as a store of beat energy and s team space, comprised between the branches of :J-sbaped tubes forming a nest of vaporia·

0

ing tubes, the ends of each of satd tubes connecting wi th t he d ru m at two diamet rically opposite points, the water inlet to the tubes being at the lower part, and the steam out.let from the tubes being at the upper par t of the drum, and t he end of ea~h t ube which connects with t he water space beiog furnished with a tuyere or diaphragm for limiting the admission of water according to the evaporative power of the tube and resisting t h e back flow of the steam so as to force i t to fl ow out t hrough the upper leg of the bent tube, substant ially as herein before described wit h reference to the accompanying drawing, for t.he purpose apeclfled ." (4 c· C6pted October 2, 1901.)

16,025. F. 0. Horenz, Dresden, Germany. Hnmldi· fying and Venttlating. [4 F igs.) August 9, 1001.-A com­bined apparatus compr ising an air fan and a steam turbine on one shaft according to this invention can be made with the t urbine

l Nov. 21, I 90 I.

CMing (when such is used) attached to the fan-bear ing. When it is d esired that the air propelled by the fan shall be humidified, the casing of t he turbine is omitted altogether, or is provided with

Fig.R.

oriflCf:s, controlled or not by taps, in order t hat the steam E xbauqt from the turbine may jo!n the t ravelling air stream. (.Accepted September 26, 1901.)

MISCELLANEOUS. 17,443. J. C. Stanley and the Cotton Seed Oil Syndt·

cate, Limited, London. Fat·Bleach~g A~p~ra~. [3 Figs.) October 2, 1900. - An apparatus accord JOg to tb.IS mven~1on for bleaching fat while in t~e liquid state. by the aottoo o~ hgbt comprises a glass house bavmg a tank a t tts base to the s1des of

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n .. , which are bolted uptiAh ts that sen ·e to ~upport a smaller tank, wbioh receives fat pumped up from the base tan k, and is pro­,·ided with distributing means by which t he fat is ser"'ed in regular flow on to a series of glass plates, also supported by the uprights. A steam coil is provided in the lower tank if ne)cssary for keeping the fnt fluid. (Accepted OctolJe·r 2, 1901.)

15.873. J. B. Stuurman, Brooklyn, N.Y., U.S.A. Cutting Diamonds. [7 F igs.] J uly 29, 1901.-Accordiog to this invention, and instend of ~rinding down t he whole exteri<' r of a diamond to form a brilliant, the atone is cu t through one

Fig.3.

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of its nxes to form two stonel', and t.bese are chipped and polished until th ey finally assume the f,hape of pyramid ;i with the lower edges ground off at an angle of about 4b deg. with t he base sur­face, ~bus producing witb little waste two finished diamonds having la rge tables. (Accepted October 2, 1001.)

16,620. J. G. Borma.nn, Berlin. Obtaintug Motive Power. [6 Figs.) September 18, 1900.-In order t o u tilise waste beat, the inventor proposes to place n. vessel, perhaps t ubular, within some substance acting as an interceptor nod

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reservoir of beat, injecting into t he vessel some volatile substance - for example, acetone, alcohol, ammonia, or .. sulphuric acid " - whose vapour under pressure is used for t he production of motive power. In one arrangemen t the evnporatin~ vessel is also the cy linder of a motor. (.Accepted September 25, 1001.)

UNITED STATES PATENTS AND PATENT PRAOTIOE. Descriptions with illustrations of im•entions patented in the

United Stntea of America from 1847 t-o the present time, and reports of trials of patent law ca.aes in the United States, may be consulted, grntia, at the offices of E.'\OIN~KR INO, 35 and 86, Bedlord· street, Strand

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