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MAKING A DUPLEX FIRE PUMP

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January, 1943 NEWNES PRACTICAL MECHANICS 109

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VOL. X. JANUARY, 1943 No. 112

BY THE EDITOR

A Scheme for ApprenticesDURING the past nine years I have on

many occasions commented on thefailure of our apprenticeship system,

and drawn attention to the great shortage ofskilled men which resulted. The facts by noware well known. The apprenticeship systemas we knew it 3o years ago was a serious affair.To become indentured you visited a solicitor'soffice with your parents, when the solicitorread over to you a frightening documentsetting forth the terms of the apprenticeship,the pocket money to be received per week,the premium your parents were to pay, thehours of work, and the penalties for breachesof the, clauses. When the solicitor had finishedreading the document you placed your fingeron a seal and said " This is my -act and deed,"and you then signed it. The documentpledged you "to absent yourself from yourmaster neither night nor day for the full periodof seven years, not to suffer damage to hisgoods, and to report others who may damageor steal them."

The period of apprenticeship was usuallyseven years, and for the first year you received4s. a week, with a penny per hour stopped forall time lost. The only holidays you couldclaim were Good Friday and Christmas Day.Each year you received a rise of 2s. until thefull period of seven years had been served,when your wages reached the large sum of 16s.a week. From that point you were expectedto spend a further two years as an improver atone pound a week. You became a journey-man, gaining ewerience, spending a fewmonths in one factory and a few months inanother, when you qualified to earn the fullrate of ra couple of pounds or so ! As soon asthe contract finished you were sacked andwere on your travels again looking for work.Little wonder then that parents decided thatapprenticeship was not worthwhile. Boys wereput to the more lucrative jobs, such as sales-manship, or entered the Civil Service, whichprovided security and a settled income, aswell as a pension upon retirement. Engin-eering provided no such prospects, and anengineer had to work until he was too old tototter to it, and then rely upon his friendsuntil Lloyd George introduced the Old AgePension.

This war, however, soon revealed the weak-ness of our production position ; there werenot enough skilled men, and the countryhas had to introduce training schemes forunskilled men and women, whilst the tradeunions relaxed their rules to permit thesedilutees to work side by side with skilled menin the factories. I hm glad to know that myconsistent advocacy of the need to return tothe apprenticeship system in an improved

form is meeting with success. I have com-municated my views on the subject to variousorganisations and Government Departments,and have found complete accord on my opinionthat the status of engineering must be raisedand the conditions made more attractive. Ihave already dealt with the scheme in practicenow for selecting suitable apprentices forengineering according to their adaptabilityand aptitude. Now the Trade Unions aretaking a hand. I have received, and amasked to pass on to readers of this journal,a memorandum from the Manchester Districtof the Amalgamated Engineering Union on thesubject of training apprentices. The com-mittee has given a great deal of thought tothe technical education of apprentices. It isof the opinion that the time has arrived fora new outlook in the engineering industry onthis miner. Having in mind the probabilitythat in the post-war period the school-!eavingage will be raised to 15 or 16, and wideropportunities for secondary school educationprovided, the way is open for a much neededadvance in the technical training of the futurecraftsmen of the industry.

Technical Education of ApprenticesThe union has an interest in the education

of its future craftsmen equal with its interestin the conditions of their employment inindustry. The tendency to employ youths onrepetition work, whilst denying them theopportunity of sound theoretical and practicaleducation, is bound, in the long run, to have adetrimental effect on the personnel as well ason the product of the industry.

A New York engineer suggests "that_ thepurpose of apprenticeship in any industrialestablishment is to develop a group of journey-men mechanics thoroughly skilled in allphases of their respective trades." This, inthe opinion of the committee, is too limited aconception. They suggest that apprenticeeducation should be soundly conceived andadequately planned, so as to enable thosecapable of using the opportunity to becomeequipped for the highest possible positionsin industry, science or technical educationitself. The aim should be to provide for thosewho desire merely to become better craftsmen;as well as for those who aspire to the highestpossible positions in the industry.

The measures suggested to achieve such anaim :are a national scheme of technicalEducation under Government control; theseparation of apprentice training frcm industryproper ; the adaptation and extension of thepresent Ministry of Labour centres forpractical training in association with thetechnical colleges ; two years' practical and

two years' theoretical training as the fullcourse; and the colfeges, as well as thetraining centres, to be staffed by teacherswith practical as well as theoretical qualifica-tions.

The cost of training, including expenses forbooks, travelling, etc., to be borne half bythe Government and half by the industry, sothat the apprentice does not suffer any financialloss during training.

The point made regarding separation oftraining from industry is the crux of theseproposals, The paramount concern of manage-ments in the industry is production, and theattention given to training occupies quite asubordinate place. Further, an apprenticewho is learning, and creating his own pictureof the industry, should not have his attentiondistracted by piecework difficulties or any ofthe other irritations attendant on production.

Technical training should be open to allwho by preliminary tests prove that they wouldprofit by it. It should be graded to suit thelimitations of each individual student. Wherean apprentice would not respond to the fullcourse of training he would be returned toindustry in accordance with his grade.

Apprentices who complete the full coursesuccessfully should be given a qualifying certi-ficate which would be a recognised standard ofcompetence.

To give effect to the above proposals it issuggested that the proposed conference ofinterested parties should recommend that eachorganisation represented at the conferenceshould submit the agreed proposals to theirparent body, with a view to calling a nationalconference designed to formulate a nationalpolicy for submi.qion to the Government.

Schools should include a certain amount ofpractical training in the various crafts in theircurriculum. At school -leaving age theyshould be presented with a card indicating thedegree of merit they have reached in theireducation and training. School examinationsshould be overhauled, so that a boy whoobtains high marks in geography but nomarks, say, in physics and mathematics, is notgraded higher than a boy who obtains areasonable average in all subjects, but lowertotal marks. In other words, total marks areno index of a boy's ability. A boy with . amemory for dates is not necessarily better thanone who cannot remember them. The presentschoolmaster's reports are often misleading,and they should be issued by some independentexaminer who will not colour the reportaccording to whether a boy is popular orunpopular, or whether he happens to be goodat sport, and has brought honour to the schoolin football or cricket.

112 NEWNES PRACTICAL MECHANICS January, 1943

The Central TeleAraph OfficeBehind the Scenes-Ingenious Telegraph Apparatus Described

By W. T. LOWE

The centre gallery of the Central Telegraph Office. Here the instruments are workingto the Midlands, Scotland, Ireland, etc. (By the courtesy of the Postmaster -General.)

FOR about ten years previous to the endof 1940, practically the whole of theinland telegraph apparatus was accom-

modated on the third. floor of the C.T.O.But this, it would appear, was simply areversion to a former state, when the officemoved from Little Bell Alley, Moorgate, in1874. The instrument room occupied thesame space, but business became so briskthat another floor had to be added to copewith the rapidly increasing number oftelegrams.

To facilitate the expeditious treatment ofthe messages in such a large organisationsome ingenious systems were introduced.One of these systems often came nearer tomembers of the public than they actuallyknew. From behind a curtained portion ofmany a small post office attached to grocers'and other shops, the clicking of worse sounderscould often be heard. In fact, whilst waitingfor stamps, you could sometimes see thetelegraphist operating.

In those days all London offices were inter-connected through a huge switchboard at theCentral Telegraph Office. A number wasallotted to each office. If, say, Wood Green had -a telegram for Forest Hill, the telegraphist atthe former office would call the latter inabbreviated morse figures. Suppose ForestHill's number to have been 125, Wood Greenwould continuously signal " A U E " untilForest Hill answered with " A U E-G "(" G " signifying proceed).

All Metropolitan offices being connected tothis board, it really was, a spectacular displaywhen in operation. When one of them calledwith their abbreviated morse numbers, alight flashed and the board operator inserteda plug in the corresponding hole, therebyconnecting the morse speaker at her elbowto the transmitting station. Consequentlyshe would pick up the plug marked 125 "(or whatever it was) and insert it in the holerelative to Wood Green's light, and so

connect the two stations. This system savedmuch time, staff and stationery.

Automatic MachinesWith the demise of morse in the Central

Telegraph Office, automatic machines fortiming telegrams were introduced. But amorse operator had to refer to the clocklivery minute of his or her duty. Here, then,was another system which had to be ingeni-ously organised.

All post office clocks are corrected at leastonce in every twenty-four hours, and where -ever one looked in the C.T.O. a clock wasvisible. It has, of course, always been

The Baudot instrument room at the C. T.O.

essential that the timing of telegrams shouldconform to a controlled system. So, to thepresent day, at certain hours, Greenwich meantime (received from the Observatory byelectrical current) is distributed either auto-matically, or by hand, to offices in directtouch, who, in turn, transmit the signal tosmaller offices. Principal offices, however,receive the sigffal direct through a chronopher.The numerous clocks were electrically cor-rected every hour, and a bell struck to denotethe hour.

Time SignalDuring the days of morse, at two minutes

to ten (later nine) a.m., the warning " Time,Time, Time," would be signalled by hand.The overseers would indulge in a littlehumour, not so much in what they said, buthow they said it. Their expression was quiteofficial. " Time, Gentlemen, please," theywould call. But 9.58 a.m. and to a.m.must have been the only moments whenhtindreds of telegraphists sent the samesignal almost at the same time.

A tale is told that, on one occasion a youngtelegraphist from a small provincial townvisited us. As is usual, at the'end of the tourthe guide asked our colleague from thedistant station what, in his opinion, was themost striking feature of the office. " Well,"the young fellow replied, " it's all bosses andclocks ! "

With the change over from morse to tele-printer, however, the clocks remained, andas far as possible all instruments were stillgeographically grouped. In one division wefound circuits maintaining touch with South-ampton, Portsmouth, Brighton, Bourne-mouth and other places in Sussex Kent,Dorset and Hampshire. Welsh cities and townsand plates in the west were nearer to eachother than they actually are in fact. Anotherdivision gave its total attention to places inthe metropolis.' Hackney, Holloway, WoodGreen, Putney, and every district in Londoncame through here on teleprinter. Scotland,Ireland, and the Midlands had their connect-ing instruments installed as family acquaint-ances-so to speak.

(By the courtesy of the Postmaster -General.)


Immediately a teleprinter was suspected ofgiving trouble it was removed to " hospital "and another substituted on the line-" at thedouble." Everything was done quickly tomaintain so° per cent. service. Shut off fromthe rest, test panels and controls occupied thesouth end of the gallery. Here was a sight

-that would have pleased the eye of many awireless " fan."

The Intelligence Duty had nothing to dowith crime, as its name might perhaps imply.No other branch of the Post Office is perhapsso closely associated with the Press as thetelegraphs. Day and night press messagescome into the C.T.O. from all parts of theBritish Isles, and the world in general. Withprinted addressed envelopes ready to hand,the Intelligence Duty deals with work foreditorial sanctums. This branch is reminiscentof the days when the Post Office dealt withpractically the whole distribution of tele-graphed news. But the cry of " wheels " (towind perforated Wheatstone slips upon), thepneumatic hiss and tapping of perforators,and the hum, of Wheatstone apparatus haveall disappeared, possibly never to reappear.Because, if it wasn't all so modern it wascertainly picturesque.

Pneumatic TubesFor short -distance communication pneu-

matic tubes gave, and still give, very usefulservice. 4 large system links up. post officessituated in the vicinity of the City andsurrounding areas. One tube runs as far asHaymarket. Another goes to the South -Western District Office, near Victoria. Thetelegrams are placed inside a small carrier.At the rate of zo miles per hour this is drawnthrough a tube by suction. Thousands oftelegrams are conveyed through many milesof tube daily.

Do you know what happened when a

Testing lines at the C.T.O.,By the courtesy of the Postmaster -General.)

subscriber wished to telephone a wire to theCentral Telegraph Office and asked for" Telegrams " ? Can you imagine thescene ! Neatly arranged telephone switch-board panels spanned tables laden withgadgets of engineering ingenuity. Colouredlights for various signals flashed silentmessages to thosewho superintended. Thisphonogram division, the largest in the world,was divided into two sectiOns. The linesfrom the switchboards in the smaller sectionconnected post offices in 4.,ondon and theHome Counties which did not do sufficienttelegraph work to warrant the installation ofa teleprinter. The larger section dealt almostexclusively and directly with the public. Atone time the operators' activities werecontrolled from a switchboard similar to thatseen in telephone exchanges, and the operatingpositions were nothing snore or less than

switchboard e x t e n -s i o n s. Later, theoperator manipulatedhis or her owncords and controlleda number of lines.He or she used twopegs-one for calling,the other for answer-ing. A dial was alsofixed to every circuit.On the board a smallelectric lamp lightedup. The operatortook a peg labelled" A," inserted it intoa relative hole, said"Telegrams," requested the su b -scriber's telephonenumber and thenproceeded with themessage. Perhapsthe subscriber's voicewas rather faint. Anattempt was made toimprove reception byusing an amplifier inwhich therm ionicvalves played animportant part. Im-provement couldsometimes be effectedby cutting out thetransmitter while thesubscriber was speak-ing. This was doneby bringing a foot,lever device into play -leaving the operator'shands free to continuetyping the message.

The conveyor band system, showing the chain -guarded drop, andslow -moving band. Note the pneumatic tubes overhead.


It must be remem-bered that the sub-scriber's period ofcontact with atelephone - telegramoperator is of muchlonger duration thanwith a telephonistat a telephoneexchange. Moreover,the former must payg r eat attention toarticulation, foreverything which heor she hears, and hasto record on a tele-graph form, is greatlyvaried. The enormous'number of telegrams

telephoned to and from subscribers' resi-dences and offices to -day justifies theassumption that those who conceived the idea" way back in the 'nineties " were gifted withremarkable foresight.

Conveyor BandsConveyor bands are used in the larger post

offices not only for carrying letters and parcels,but also for carrying telegrams to and frominstrument tables. In the old C.T.O. therewas an elaborate structure through whichthousands of telegrams passed daily. Withinchromium -plated bars or rails which formeda sort of barrier from the operating positions,men and women were seated at long tables.Each one had a book in which the name ofevery telegraph office in the United Kingdomwas printed. They sorted telegrams, coming

The cable room at the C. T.O. Morse -key transmission of telegrams which are relayed toships on the high seas.



from all points of the reorganised CentralTelegraph Office, for their respective destina-tions. Bands of webbing travelled at arm'slength inside a frame. You had to be quick tofollow the progress of any particular message.Slow -moving hands brought packets oftelegrams, or, as they are officially known,circulators, to the sorting clerks, who placedeach telegram on one of the appropriatebands, which, running inside the frame,carried it away to an instrument table ; thephonogram room ; and other parts of thebuilding.

Messages received on teleprinters and inthe phonogram room were also carried to thesesorting tables by conveyor bands. Thetelegraphist dropped the telegrams into aV-shaped trough at the back of the instrumenttable. At the bottom of the trough a movingband took the traffic to a parent band, andthence onward to a chain -guarded drop.Tumbling down this drop, the messagea`ighted upon the slow -moving band. to be

picked up by a sorter and circulated to are -transmitting circuit, or to its destination.Up through the ceilifIg it took the telegramsfor the phonogram room. Down through theceiling it brought them straight from thetelephone -telegram operator to the slow -moving band. This contrivance was really awonderful piece of work, and in a modifiedform it may also be seen in other largetelegraph stations in the British Isles.

Such were the surroundings in which thestaff of the Central Telegraph Office workeduntil December, 194o.

The Cable RoomThere was, however, one branch of the

C.T.O. which modernisation had not affectedquite so much. Considered to be the mostimportant section, both publicly and diplo-matically, the cable room stood apart fromthe inland telegraph galleries-as the hugerooms were officially called. Cable operators

were really unofficial miniature ambassadors.Working direct to many places on theContinent, a knowledge of at least French andGerman was essential. And they had to usetact, of course. Up to the eves of August 4th,1914, and September 3rd, 19393 they workedon German lines as if nothing had happened,or was likely to happen. They plodded onuntil the fatal moments, and nobody can saythat any one of those fellows contributed to adiplomatic difference of opinion. Since 1889,morse and many other systems have assistedto make the cable room an imposing spectacle.From here, also, messages were, and, of course,still are, transmitted direct by remote control,through wireless stations, to ships sailing theseven seas and places thousands of milesaway.

The most spectacular branch of the C.T.O.which has come under the control of cableroom men is the " Picture Telegraph," anarticle on which appeared in PRACTICALMECHANICS for November, 1942.

CombatingExplosive Incendiary BombsThe Anti -personnel Incendiary Bomb, Now Used by the Germans, Loses Much of its "Sting"

If Dealt With in the Proper Manner

THE use of fire -creating devices in wardates back to the earliest days ofwhich we have record. From the

distant days when the blazing pine torch andfaggot were used as weapons of destruction,theterrifying power of fire has been developedthrough the stages of the fire -ball, the flamingarrow, red-hot cannon balls and the fire -ship,to its present devastating form.

Although the methods employed now differfrom those used by our ancestors, the objectsprompting their use (namely, to cause con-flagrations in the enemy's territory, with thepossible disruption of the defence and normalservices, and to create a state of chaos, panicand demoralisation among both defendersand civilians), are unchanged. During thiswar, the fire " blitz " air raids have beenstriking examples of how far the developmentof fire -creating devices has progressed, but inspite- of the weight of the attacks and theeffectiveness of the modern incendiary bomb,the enemy failed utterly in achieving his realobject. The fire -ship of the past has now beensuperseded by the large airborne " bombers "of to -day. In place of a single source of fire,we now have to contend with the possibility ofeach enemy raider carrying several thousandsof incendiaries ; yet, in all of our " blitzed "cites and towns the enemy has failed tocreate the chaos, panic and demoralisation onwhich he had backed to complete the destruc-tive power of his raid. The frustration of theenemy's hopes was due not only to the fortitudeof the public, but to the way it put intopractice the instruction it had received,through classes, pamphlets, the press andradio, on how to deal with incendiary bombs.Experience has shown that a modern fire" blitz " can be on such a scale that theN.F.S. could not cope with it, but experiencehas also shown :that properly instructedcivilian fire fighters can, by safeguardingtheir areas and thus relieving the pressureon the other Services, make a valuable con-tribution to the frustration of the enemy'shopes. Proof of this is provided by the factthat belligerents, in efforts to defeat the fire -watchers, endeavour to alter the type ofattack by the introduction of new types of

By JOHN TOWERS

bomb. Thanks to the prompt action by theMinistry of Home Security and the localCivil Defence authorities, instruction in theform of leaflets, lectures and demonstrationswas soon available to all fire fighters con-cerning the most effective methods of com-bating the new devices produced by theenemy.

Types of Incendiary BombsUntil quite recently, the chief fire -creating

devices used by the enemy have been thekilo magnesium bomb (known as the

" Elektron " bomb) and, to a much lesserextent, the Ito kilo oil bomb. The " Elek-tron " bomb is gin. long by tin. in diameter.The whole construction, except the fins, isof incendiary metal and burns for aboutro-15 minutes after throwing off pieces ofmolten magnesium 'in all directions for,approximately, the first two minutes. It fallswith a velocity of 35oft. per second, and canpenetrate most types of domestic roofs.

A variation orthe above is known as thekilo magnesium with tail explosive

charge. This is simply the same bomb asmentioned above, with the addition of anexplosive charge fitted under the fins. Itfunctions the same as the " Eiektron " up toapproximately two minutes after impact, whenthe explosive charge is set off which causesmolten and solid metal to be projected,therefore, some form of cover-a shield, anupturned table or chair or other reasonableprotection-is advisable when tackling it.

Anti -personnel Incendiary BombAs the name implies, this incendiary is an

effort on the part of the enemy to preventfire fighters reaching the spot where the bombhas dropped, until it has been able to set upa serious fire. The bomb itself is the ordinary " Elektron "

fitted with a 71in. nose at its base. This -addition houses a time fuse and 31 ozs. ofT.N.T. which is capable of producing anexplosion comparable with the Mills handgrenade. On impact, the incendiary portioncomes into operation in the normal manner,

but, at the same time, the slow fuse for the ex-plosive content is brought into action . The delayon this fuse varies from I minute 20 secondsto seven minutes, therefore, until the explosiontakes place, it is essential to make the utmostuse of cover while tackling the incendiaryportion which is already doing its work.What forms effective cover greatly dependson the scene of the incident ; a 41 --in. brickwall is considered desirable, but the mainthing to bear in mind is to keep well down andtake advantage of every bit of cover availableuntil the explosion has taken place, whenthe fire can be attacked more effectively.The construction of the bomb is shown on theopposite page, together with an artist's im-pression of an incident in which he showsthe first sign of the incendiary portion inaction, and-at the bottom of the page-thefire fighters attempting to check the fire frombehind an outside wall, thus getting maximumprotection from the explosion which is alsoshown. A lath -and -plaster or breezepartitioning wall does not offer safe cover,and to emphasise this, the artist gives us aview of one of the partitioning walls of theroom in which the incident is taking place.

Points to be remembered about the anti-personnel incendiary are : The explosivecontent is rendered effective by the removalof a wire-shown in the illustration-whichfollows the contour of the bomb, and one endof which holds in position a safety pin, whilethe other end terminates at a small metal discwhich normally rests on the top end of thefins. The passage through the air causesthe disc and wire to be removed, thus releas-ing the safety pin ; one should listen forthe wires falling slightly after the bombs, asthis will give an indication of their type.

It is possible for the 71in. explosive portionof the bomb to become separated-by theforce of impact-from the incendiary section,so keen obsenttion is necessary. Theweight of the complete bomb is 5 lb., thusthe force of impact will be greater than theordinary " Elektron " and the bomb willpenetrate an additional floor, but as it is noseheavy, it is not likely to fall inside windows,etc.


The Explosive Incendiary Bomb

tart' -

--Cap with wirecohneetk.,nsafety pin

The anti -personnel incendiary bomb - isshown on the left, and above, a containeris seen discharging its load of incendiaries,one of them making a hit on the house

below.

(--.);f)/C? e ftPdd

The fire-fighters attack the fire from outside the housethus securing the protection of a 9in. brick wall. Note

the effect on the breeze partitioning wall.


Measuring -the energies and other properties up to fifty billion electron volts is the functionof this cloud chamber apparatus at the California Institute of Technology. On the right, scientists

are installing camera apparatus.

SUSPENDED, in total darkness, betweenthe pole faces of an electro-magnetsetting up a force to,000 times more

powerful than the earth's magnetic field, acloud -making chamber awaits the onslaughtof a charged particle from outer space.Suddenly, far too tiny for the strongestmicroscope to bring it within human view, aparticle flashes through the chamber, hurtlingearthward r5o,000 miles a second with anenergy, weight for weight, 400,000 timesgreater than that of a one -ounce rifle bulletzipping 3,000ft. a second toward theenemy.

Yet, with this new cloud chamber, whose24in. diameter and the magnet with whichit is virtually surrounded, make the cosmic -raytrapping device, Dr. Carl D. Anderson,California Institute of Technology physicist,hopes to measure the mass behaviour of thelittle-known mesotron, and the energies andproperties of other cosmic ray particles whoseenergy touches the stupendous figure of50,000,000,000 electron volts. When youremember a lighting flash discharges at therate of one to two million electron volts, youget an idea of the energy raining down fromouter space upon the new cloud chamber.

Though completely invisible themselves, inthis ingenious device the rays set off a trainof events that leave a temporary visible record.of their path and dual motion picture camerassnap stereoscope pictures of the trails ofwreckage left in the wake of these cosmicjots. By measuring the curvature of thesetrails later, Dr. Anderson and his associatestake an important step toward solving thesecrets of the universe.

How does science photograph invisiblecosmic projectiles passing lenses at 9,000,000Miles a minute ? Where do cosmic rays comefrom, and what are they ? What's thepractical value of such studies ? Physicistscan answer these questions only in part.From the studies eventually will come in-formation which will advance our knowledgein biology, meteorology, geology and astro-physics.

Details of the Cloud ChamberLet's look in on the cloud chamber, housed

in a light -proof cabinet, for an intimate viewof this scientific legerdemain. We see thehuge magnet, lying horizontal on two concrete

beds. Enclosed within its frame are the fieldcoil, the cloud chamber, cameras, fast -actionillumination lights, a pair of trigger devices,an air exhaust system, and a complicated arrayof wires, switches and relays.

It so happens that the cosmic rays strikethe apparatus about once every minute. Whena particle passes through a pair of GeigerCounters, one placed above and the otherbelow the cloud chamber, setting both offsimultaneously, a picture is taken. Thisprocedure is not simple ; as a charged par-ticle approaches the cloud chamber, it passesthrough the first counter, which is simply agas -filled metal cylinder through which isstretched a fine wire, and rushes on throughthe chamber and the lower counter. Whenboth are hit simultaneously, rapid dischargesof electricity occur between the wires andcylinders, and these discharges are ampli-fied to operate relays and other devices.

During the incredi-bly swift passagethrough the chamber,the particle collideswith a large numberof gas atoms along itspath, tearing off elec-trical charges fromsome, and turning theminto electrically chargedions. This procedureoccurs before your eyesconstantly, and younever witness the trans-formation. But in thechamber the stage isset.

On the floor of thechamber is placed asmall quantity of ethylalcohol. Shortly thespace becomes saturatedby evaporation. Nowall is ready. A chargedparticle passes through,leaving 4,800 to 7,20opairs of ions alongits two -foot path. Asthe counters trigger -offthe apparatus, the blackvelvet -covered metalback is pulled out a barehalf -inch, expanding

StudyingParticulars of a_ New Cloud

Energies and Properties

By ANDREW R. BOONE

the atmosphere to per cent., causing it to cool25 deg. F., in a flash. As a result of thecooling, the moisture condenses and, comesout as a gentle rain. No dust being present,the droplets grow on the shattered ions, andfor a moment leave a string of dropletsresembling miniature beads-beads of suchsubstance they can be readily photographed.

Photographing the IonsThe instant the beads form, two lamps-

quartz tubes fitted with electrodes and filledwith argon gas, through which a charge ofelectricity is caused to pass-flash. Theirbeams, focused through auxiliary lenses,flood the chamber for t/too,000 of a secondwith a brilliant blue light equivalent inintensity to that produced from a pair ofmedium size flash bulbs.

With that flash, the picture is taken. Nowtwo electric motors, started by the impulsein the " trigger -off " tubes, move the 35 mm.film one frame, and the cameras, shuttersopen, are ready for the next atom -blastingarrival of some as yet unidentified particle.

No human eye ever will see directly theparticles speeding through the cloud chamber.Yet by measuring the curvature of theirpaths and making other complicated deter-minations, physicists have learned muchabout the building blocks going to make upthe universe.

Let's tear the cover from one of the largerbuilding blocks. This is a molecule, of whichall matter is composed. The molecule is thesmallest block having definable properties.Could you isolate a molecule of sugar fromone of the grains now so precious, you wouldfind it sweet to the taste.

Small though it be, the molecule is sub-divided into two or more of the 92 elementsthus far discovered. The sugar moleculecontains atoms of carbon hydrogen and oxygen.We're only part way on the road to discovery

Camera is hoisted to top of magnet, and lowered into place againstcloud chamber.

January, 1943 NEWNES PRACTICAL MECHANICS

Cosmic RaysChamber for Measuring theof Cosmic Ray Particlesof ultimate units when we reach the atom.Break an atom apart, -and you find it made ofa solar system of electrons, which are in-finitely tinier particles, each carrying anegative charge of electricity. The centrecore carries a positive charge of electricityequal to the total charge of all its surroundingelectrons.Protons and Neutrons

We must subdivide the core into its partsbefore the picture is complete. This nucleusis composed of two kinds of particles, protonsand neutrons. The protons weigh 1,840times more than the electrons, mass for mass;and for each electron in the outer fringes,there is an equivalent proton in the core. Ifthe atom contains six electrons, there also aresix protons. Filling the intermediate spaceinside the core are heavy particles calledneutrons. These carry no electrical charge.

You must add to this list, for sake of

Interior of cloud chamber is illuminated by twospecial lamps focused through lenses. Eachlamp, filled with argon gas, gives flash lastingIlloo,000-second, equivalent in intensity tomedium size flash bUlb (half of Wabash No. 2).

completeness, the positive electron, or posi-tron, a very light and unstable particle ;the mesotron or meson, which may be eitherpositive, negative or neutral, and weighs200-250 times more than the electron; andparticles of no mass and no charge-thegamma or X-ray, now called photons.' In1932, Dr. Anderson snapped the first pictureever made of a positive electron, and for thisoutstanding feat received the Noble prize.That epochal pictige caught the positron withan energy of to,00d,000 electron volts, only1/5,60o the energy of other particles whosesecrets he hopes to trap with the newapparatus.

MesotronsThe first evidence for the existence of the

particles, now known as mesotrons, was

announced in 1936 by Drs.Anderson and' Seth H.Neddermeyer. -This announce-ment was based largely on datathey had lathered while makingexperiments on the summit of

117

lations too complicated for review here. Hegets no pictures of neutron and photon pathsbecause they do not ionise and shatter theatoms enough to be caught in their headlongflight from outer space. The proton, however,being very heavy, not only shatters more

At intervals, following a series of photographs, a projector unit is attachedto each camera, and the pictures projected through the same optical systemon to an opal glass for study and measurement of curvatures. By thismeans, mass of mesotrons and energies of other cosmic ray particles is

determined.

Pike's Peak at analtitude df tzt,000ft.above sea -level.

Now Dr. Anderson'scameras are beginningto trace the paths ofprotons, electrons andmesotrons. How heidentifies, one fromanother involves ob-servations and calcu-

atoms than other particles ; its very massresists the magnetic field, causing it to dashthrough the chamber with less curvature.

Early cosmic -ray researchers thoughtphotons and electrons gave the rays -theirgreat penetrating pcwer, carrying themthrough hundreds of feet of rock, and deepinto the sea to recording instruments.Whether they were protons, electrons orphotons was a question unsolved for severalyears. Now the particles penetrating the

atmosphere and reachingthe earth are known tohe mainly mesotrons,most of which areproduced in the upper at-mosphere. How they arecreated is a deep mystery,yet a few facts about theirbrief life have been devel-oped. The mesotron is born,flashes through the atmos-phere and dies-in onemillionth of a second. Thatis, carrying either a positiveor negative charge, andsometimes being whollyneutral, the mesotron dis-integrates, experimentsindicate, into other par-ticles.

ProgressDespite the war, cosmic

ray research is movingforward. From the Cal -tech cloud chamber, mostpowerful in its ability tomeasure the tremendousenergies of the cosmicjots yet developed, prob-

Dual 35mm. movie cameras photograph track of cosnuc-ray particles ably will come informationthrough two aluminised mirrors. Coating is applied to front surface applicable to everydayof glass, ground optically flat. Mirrors are used to increase focal living and open new heti-

distance, on account of restricted space. zons to scientists generally.


jet PropulsionThe Possibilities of a New Method of Propulsion for Aircraft

By S. J. GARRETT

NOW that flight speeds have reached suchhigh figures, limitations lie close aheadregarding the capabilities of the air -

screw in converting engine power into thrust.Scientists and engineers are therefore seekingalternative methods of propulsion in whichsuch limitations are avoided, the generaltrend of such research being towards jetpropulsion.

In any aircraft a continuous forward thrust isobtained by reaction against the column of airswept back by the airscrew, i.e., a mass ofair is thrown backwards and the force appliedfor this purpose to the air. reacts on theaircraft with a forward thrust. The essentialdifference between jet and airscrew propulsionis that the latter deals with a large mass of airat a low velocity (Fig. s), while the jet uses asmaller mass of air and imparts a highervelocity to it.

Slipstream SpeedIn the normal fighter type of aeroplane

with a speed of, say, 38o miles per hour, aforward thrust of about r,000lb. is necessary,and to give this an engine of about 1,250 h.p.is required, throwing back by means of itsairscrew about 5o tons of air per minute witha velocity of about 12 miles per hour. Thisvelocity appears quite low at first sight, butit should be remembered that it is added tothe forward speed of the aeroplane, so thatrelative to the aeroplane fuselage the slip-stream speed is getting on for 400 miles perhour. Also, the slipstream velocity varies withthe speed of flight ; it is perhaps ten timesthis speed with the aeroplane standingstationary on the ground, and it falls off as

Engine

Or, I

Multi stageblower

the forward speed Of the aeroplane increases.This is one of the factors restricting theperformance of an airscrew at high speeds.The use of variable pitch greatly extends theutility of the airscrew, but it only postponesthe limitations without removing them.

It will be seen from the above that theairscrew deals with very large quantities ofair at high aeroplane speeds, but that acomparatively small velocity is imparted to it.The same thrust can be obtained by throwingback a smaller mass of air at a higher velocity.For instance, if 5 tons of air per minute ispushed backwards at 12o miles per hour, or0.5 tons per minute at 1,200 miles per hour,the same thrust will be obtained ; thisalternative offers certain advantages, which isjust what is aimed at by jet propulsion.

a system would work, but the overall efficiencywould probably be less than with the usualairscrew system.

If, however, the air is heated after leavingthe blower, and before reaching. the jet, itsinternal energy can be greatly increased, andit is capable of doing much more work, andproducing a bigger thrust. A convenientmethod of doing this is shown by Fig. 3.The engine drives a multi -stage centrifugalblower as before, but the air is delivered into

Large slipstreamof /ow velocity

Fig. J.-Diagram illustrating the slipstreamof an airscrew.

a combustion chamber, into which a spray ofpetrol (or other fuel) is injected and keptburning. The air is thug heated to a hightemperature, which will increase the pressure.in the combustion chamber. Both the jetand the blower must be suitably proportionedto obtain the required pressure. If the jet issmall the blower must be capable of maintain-ing a high pressure, the velocity from the jetwill then be high, but the mass flow will besmall. On the other hand, a large jet willresult in lower pressure and lower jet velocity,

Small slip stream)of high velocity

Multi -stage BlowerAn obvious step towards obtaining the

required small, high velocity slipstream isthat illustrated in Fig. 2, where the enginedrives a multi -stage centrifugal blower de-livering compressed air to a jet pointing tothe rear of the aeroplane, from which the airescapes at a velocity of several hundred milesper hour, the reaction producing the requiredforward thrust. There is no doubt that such

Fig. 2 (left).-Dia-gram showing how ahigh - velocity slip-

stream is obtained.

Fig. 3 (r i g h t). -Method of using acombustion chamber inconjunction with a

blower.

but the mass of air dealt with will be greater.The proportioning of these parts is a matterof ascertaining the optimum conditions inorder to reach the highest attainable efficiency.

Gas TurbineUp to this stage the usual aero engine has

been assumed to be supplying the powernecessary to drive the blower, but so muchenergy can be made available in *the com-bustion chamber that it is possible to use partof it to do the work of the engine; The nextstep, then, is to dispense with the engineentirely and to drive the blower by means

Fig. 4.-Using ablower driven bya direct - coupledturbine for pro-ducing a high -velocity slipstream.

Mu/ti stageblower directcoupled to

turbine

of a direct coupled turbine driven by theheated gases, as illustrated in Fig. 4. , Aproportion of the contents of the combustionchamber is led off to the turbine inlet, theexhaust being directed to the rear to assistthe propulsive effort ; the amount of thrustobtainable from the turbine exhaust dependsupon the design of the turbine, and the amountof energy it is found possible or desirable toextract from the gases. This then is an outlineof the principles underlying jet propulsion.

It will be' observed that the completesystem becomes a form of internal combustionengine working on a continuous instead of theusual intermittent cycle. Suction and com-pression are carried out continuously by theblower, combustion is a continuous processin the combustion chamber, while the con-tinuous flow from the jet is, of course, theexhaust.

Many practical difficulties have to be over-come before success is aohieved, not the leastperhaps being the construction of a turbinewheel, and nozzles, to stand up to the erosion,etc., due to the high temperatures andvelocities. The progress of aviation at highspeeds and high altitudes demands some suchdevelopment, and the scientist will no doubtsee that the demand is met in due course.

Jet versus Rocket PropulsionJet propulsion should be clearly dis-

tinguished from rocket propulsion, which issometimes referred to in discussions on inter-planetary communication. In jet propulsionas already described the mass thrown back-wards is drawn from the surrounding air, sothat it would be quite impossible to consider

Fuel spray

// '

Combustionchamber

using such a device for a journey, say, to themoon. But in the case of a rocket the wholeof the matter ejected is carried in the rocketitself which is therefore entirely independentof the atmosphere, except that the lattercauses resistance and obstructs free travel.The combustion process in the rocket neces-sarily requires oxygen, but this also is carried(in chemical combination) and not obtainedfrom the air. Although various fantastic (butnot necessarily quite impossible) suggestionsare sometimes put forward it is improbablethat rocket propulsion will be used as themain source of power for terrestrial air travel.

Turbineexhaust

11.


AntiHow

THE previous article was devoted toflashlight work and explained how itwas possible for a beginner with

any make of camera, and without any specialapparatus, except one carton of Johnson'sflashpowder, costing is. 3d., to make eightor to exposures. While flashlight is obviously" artificial light," yet it is usually consideredas a class by itself, and is not always includedunder the abode heading.

Artificial lighting is by no means new,for professional photographers have used itfor many years in their studios, and it hasbecome a very important item in their studies ;in fact, much of their work would be im-possible if they were not able to fit up nestsof, or single special lights for obtaining certaineffects quite unobtainable by natural lighting.These installations are often a most expensiveitem in the equipment of a studio, and there-fore not one of consideration for the greatmajority of amateurs ; but in these days ofhigh -watt and photo flash -bulbs, flood andspot lights and power plugs, it is possible foran amateur with a moderate amount ofpocket money to acquire much skill, togetherwith a considerable amount of pleasure, inthis branch of the hobby.

Selection of ApparatusThe selection of the apparatus must be

left to the individual. I am only going to try to interest those of you who wish to tryyour hand at the work in a small way, andwho have to be content with the use of thedining -room, or a small darkroom.

In describing the use of flashpowder Ilimited it to the taking of portraits, andthose hints are equally applicable to the useof all other artificial lighting apparatus. Injust the same way the subjects to which Irefer in this article can be taken by means offlashpowder.

One piece of apparatus which came intomy possession a few years ago and which Ihave found very useful, consists of a deep,bowl -shaped reflector, plated inside withchromium, and fixed to a short stand which isadjustable to almost any angle ; attached toit is a fairly long lead fitted with an adjust-able holder for use with an ordinary lampbracket or power plug; the actual bulbsupplied with it is a 250 -watt Nitrophot. Ibelieve the lamp is of foreign manufacture,but at the time it was purchased in London.The light which such a lamp gives enablesme to take a portrait or a table -top subjectwith an exposure of half a second, using afast film, such as a Selo H.P.3, and a lensaperture of F8. This lamp gives plenty ofscope, as for instance, if I want to overcomeheavy shadows, when taking a portrait or astill life study, then by stopping down mylens to F16 or 22, I can, while the exposureis being made, hold the lamp for part of thetime on the right hand side of the camera,then change to the left, and still have time fora short top light by raising the lamp abovethe camera.

While on the question of lamps and lightsit should be understood that it is not neces-sary to have high -power lights for this work ;I have seen a portrait taken on an IlfordHypersensitive Panchromatic plate with thelens set at F3.5, and the only illuminationwas that given by a couple of matches heldby the sitter and kept alight for a matterof 15 seconds. Ordinary electric lights of 6owatts can be used quite successfully withopen stop and a fast film, the time required

cial Light Phototo Obtain Successful Results With Ordinary

By JOHN J. CURTIS, A.R.P.S.

being about half to one second. A nest ofthree 6o -watt lamps makes a very usefulhelp fof practically any subject, but, whenfitting this set, care must be taken to seethat the circuit is not being overcharged and,where it is on the ordinary household in-stallation, warning should be given to the

An untouched portrait taken with a Nitrophot250 -watt lamp. Exposure sec. F6.5 Selo -

chrome film.other members of the family to switch otherlights off while you are using the nest.

Photoflood LampsThe very excellent Photoflood lamps that

in normal times are obtainable, usually areof 15o watts, and give a candle power ofapproximately 1,000 ; they have a fairlylong life. A Nitrophot of 50o watts also hasa candle power of about t,000, and a lifeof about ',coo hours ; extra care is requiredwith this type, and it is inadvisable to use(Below) The Hol-born Multi -floodoutfit, consistingof aluminiumreflector withwire stand jointedto be employedat any angle.

(Above) HolbornPhoto -spot, aportable spotlight,operated from

any circuit.

more than one at a time, because it takesabout 21 amps. Those readers who arefamiliar with electric lighting and its pecu-liarities, will be able to counteract any risksof fusing, overcharging, etc.

If I were fitting my room for much erti-ficial light work, I should install single lightsinstead of nests, and have plenty of lead so

raphyCameras

that each lamp could he moved to any positionrequired ; also, I should certainly use therubber -covered flex.

Sometimes it is possible to get very beautifullighting effects by combining daylight withone lamp, the results will usually be very softwithout any hard shadow or lines.

Those who use both orthochromatic andpanchromatic films must remember thatthe pan. variety, although it might be thesame speed, will require less exposure thanthe ortho. films, becatAe they are muchmore sensitive to the red rays which are givenoff by the lamp.Exposure Times

Dark walls increase exposure times justas much as dark clothes on the sitter; infact, the general surroundings are an import-ant factor because it is the light reflected fromthe subject, and decoration of the room, whichacts on the emulsion, and therefore must beconsidered when calculating the exposure.

There is still one other factor which mustbe given some thought and I must, for thebenefit of any reader who has not experi-mented with indoor photography, explain thisfairly fully ; it deals with the actual power ofthe lighting, and the distance from the subject.If the light at a distance of 4 feet frcm theperson you are photographing requiresI second, then at 8 feet it would want 4seconds, and at 12 feet no less than 9 seconds;the reason for this increase being that thevalue of the light reaching the subject fallsoff inversely as the squire of the distance.I will show how this can be calculated byfigures. Take the square of 4 feet, 4 x 4 -16which requires I second. 8 feet would be8 8 -64. 64 divided by 16 =4. 12 >:1244 which divided by 16 gives 9 seconds asthe exposure required at 12 feet from thisparticular light. I am, of course, onlyassuming t second for the 4 feet for myexample, but this rule of increasing the timestands for any close-up when the distancehas to be changed ; the only modificationwhich can be allowed is when the generaldecoration of The room is lighter and thereforegives greater reflection. Many amateurs failto get successful results at their first attemptsbecause they are not aware of the greatdifference distances can make to the powerof the light.

Reflectors 'With regard to the use of reflectors and

diffusing screens, they are unquestionablya great help with artificial lighting and Ithink more so than with flashlight works

because the exposures are longer and thcreforeunder control. It is a mistake to allow thefull effect of the light to fall on the sitter, thetable -top study, or any other subject, exceptingactual copying of plans, drawings and such like,which require full lighting. The use of adiffusing screen made of nainsook, japanesesilk or similar material will, if placed betweenthe light and the sitter, prevent hardness, andif this can be employed so as to throw mostof the light on to a reflecting screen-whichshould be placed at an angle to receive thelight, and at the same time reflect it onto the sitter-then a soft lighting resultof a pleasing character will be assured if theexposure is correct.

A large piece of white paper carefullystretched on a light frame of wood or a child'swooden hoop makes a very good reflector.

Care must always be taken to prevent thelight falling on the lens.

120 NEWNES l'RACTICAL MECHANICS January, 1943

Exposure FactorsYou will have noted that there are four

important factors in artificial lighting whichmust be considered when estimating theexposure, and these apply to practically everytype of subject : portraits, studies of thefamily pets, copying paintings, photographingmodels or Postage stamps, or table=top andstill life subjects. They are :

(r) Power of light and the amount of lightreflected from the surroundings.

(2) The speed of the film.(3) The stop of the lens.

(4) Thz dist ince between the lens and thesitter or object.

Usually after the first two or three attemptsyou will find that you have gained quite a lotof useful information, and that it is easy tocalculate the exposure successfully ; especiallyif you try to standardise the work, by usingalways the same make of film and the samestop.

Correct developing is very necessary withall artificial lighting ; hardness is a featureof most first efforts, but this can be overcometo a great extent by the use of a developerknown to give " soft " negatives. Such

a developer is Azol, and if the tables arefollowed then correct development is assured.The selection of printing paper is one whichcannot be dealt with in this article, except toadvise a matt surface, normal grade bromidepaper.

Finally, I do not want anyone to think thatthis branch of photography calls for expensivecameras obviously you would expect betterresults from such, but it can be done withordinary folding types, and even with the boxform of camera, but with these latter caremust be taken to measure the distances, if itis not possible to focus with them.

A bomb train arriving alongside a Stirling bombcr with its " cargo for to -night." This aircraft's full load is eight tons of bombs.

The World, ofThe Mosquito German 45 -ton 'Plane :

The MosquitoBUILT by the de Havilland Aircraft Co.,

the Mosquito is probably one of the bestaeroplanes of its class yet constructed. Atwin-engined monoplane, it has a span of54ft. zin., length overall of 4oft. 91in., anda height over propeller tip of 15ft. Sin. Itsspeed brings it into the top fighter class,while the duration of flight is considerable.The Air Ministry describe the machine as areconnaissance bomber, and it can carry auseful load of bombs over long ranges. Itsarmament is stated to consist of four 20 mm.cannon, and four .3o3in. machine guns.Another interesting feature is the fact that theMosquito is the first all -wood operationalmachine of this war. The power unit are twoRolls-Royce engines.

German 45 -ton 'PlaneTHE German transport plane, the Bloehm

and Voss 222, recently shot down in theMediterranean, is probably the largest aircraftof its kind in the world. It has six enginesand is capable of carrying 8o fully armed men.It is much larger thap the Halifax and theFlying Fortress. ,fl'he B.V.222 is poweredby B.M.W. radial nine -cylinder D.C. air-cooled engines, and is stated to have beendesigned before the war by Dr. Vogt -for theLufthanse world air routes. Fully loaded themachine weighs about 45 tons. Its cruisingspeed is 15o m.p.h., with a top speed of 190m.p.h. at io,000ft.

A.T.C. is Now World-wideFOLLOWING; Britain's lead, air training

organisations are now firmly establishedin several Dominions, and many thousands ofyoung'Australians, Canadians,New Zealanders,\Vest Indians and Rhodesians, are hard atwork training to enter their own air forces

AviationLong-range Fighters' Successes

or the R.A.F. The U.S.A., too, has recentlystarted the A.T.C. of America.

Long-range Fighters' SuccessesONE of the outstanding features of our

intense air activity preceding and duringthe present offensive in the Middle East hasbeen the success of our long-range fighters.

These aircraft have recently operated mainlybehind the enemy lines in North Africa, andparticularly along the important coastal zonefrom Alamein to beyond Tobruk. One squad-ron, the first to be established in the MiddleEast Command, completed well over 300flying hours in the month preceding theoffensive and, in the course of widespreadactivities, came through without the loss of asingle aircraft. During the month pilots of

the squadron destroyed three Heinkel r r is,one Ju. 88, one Savoia 8r, one Fieseler Storchand one Macchi 202, in addition to severelydamaging a number of Ju. 871.

Germany's Four-engined BomberTHE Heinkel 177 is the first German aero-

plane built as a four-engined bomberto fly over this country. Outwardly it appearsto be a twin-engined monoplane, but each ofthe engine nacelles contains two Mercedes-Benz 601 engines of 1,15o h.p. The twoengines, placed side by side, arc geared todrive one airscrew. The Heinkel firmpatented this form of engine installation in1936, but the first aircraft built on theselines did not appear until after the war began.

Recently one was shot down over theBristol area and others have been reportedover various parts of Britain. This machineis a heavy bomber in the class of the Lancasters,Stirlings and Halifaxes. It is claimed that itcan carry a bomb -load of something over sixtons. Maximum range is phenomenal-justover 7,000 miles.


MASTERS OF MECHANICSNo. 81-Sir Samuel Morland, an Early Inventor of Romantic Renown

KING CHARLES II, the Merry Monarch,had many good traits in his character.Among them was his enthusiastic and

sincere encouragement and patronage ofscience, invention and mechanics.

Charles, indeed, became so interested inmechanical invention and its possibilities thathe went so far as to create a royal appointmentwhich he named " Master of Mechanics."The holder of this post was supposed to benot only a mechanician of note and a provedinventor, but also a general scientist of thenew and progressive school which was thenarising.

The first holder of the appointment of"Master of Mechanics" which Char/es IIbrought into being immediately after therestoration of the Monarchy in 166o was SirSamuel Morland. As a mechanic and anall-round inventor, Morland undoubtedlypossessed considerable ability. Indeed, hefigures as one of our earliest mechaniciansand as a pioneer of steam power in Britain.

Old Samuel Pepys, the celebrated diarist,who was a contemporary, declared thatMorland " was looked upon by all men as aknave." And Pepys, despite his violent likesand dislikes, was, above all things, a prettyshrewd judge of character.

Much of Morland's history is obscure, and,in particular, the precise circumstances inwhich he evolved his various inventions. Sofar as can be ascertained, he was definitely anoriginal inventor.

Political AppointmentsThe earlier life of Samuel Morland was

taken up with political affairs. He seems tohave been born about the year 1625, the sonof a Berkshire clergyman. He was educatedat Winchester School and at CambridgeUniversity, after which he embarked upon aperiod of continental travel. During theProtectorate of Oliver Cromwell (1653-1658)Morland formed one of the embassy toSweden. Afterwards he was appointed to theoffice of assistant to Cromwell's secretary.After a time he began to feel dissatisfactionwith the treatment he received in this office.Resentments arose rapidly in his mind, andwhen, ultimately, he accidentally becameaware of a plot against the life of Charles II (whowas then living in exile), it did not take himlong to inform the King's friends of themachinations of the Cromwellian party.

It was in this manner that Morland cameinto favour with Charles. When the latterentered triumphantly into London in 1660,after the death of Cromwell, and was restoredto the English throne, he awarded Morland abaronetcy, and a pension, in addition tomaking him the first occupant of the newly -created post of " Master of Mechanics."

He now gave himself up to mechanicalinvention, it being from this point in hiscareer that Morland's main inventions date.

As time went by he gained a good deal ofnational celebrity on account of his mechanicalpursuits and his scientific studies. His housein London, which, if we are to believecontemporary statements, was packed withmechanical models. and apparatus of alldescriptions, was a resort of all who madepretensions to an interest in scientificachievement.

Early InventionsAmong the earliest of Sir Samuel Mor-

land's inventions is that of the speaking -tube, or Tuba stentorohornica, as he called.it.

Scientific historians have long disputedMorland's claim to the invention of theprinciple of speaking -tube and sound -conduitconstruction, since the German Jesuit,Athanasius Kircher (1601-1680) undoubtedlydescribed the principle and construction ofspeaking tubes in his scientific writings. Theclaims of Morland and Kircher in thisrespect are fairly equally divided. PerhapsKircher was first in the field with his de-scription of the principles of sound conduc-

Sir Samuel Morland.tion through tubes, but Morland certainlyseems to have brought the principle to a morepractical conclusion.

Morland invented several types of waterpumps and machines actuated by waterpower. In 1684, he was sent to France toexecute some waterworks for the FrenchKing, Louis XIV, a project which he carriedout with distinction. It has been claimedthat Morland was the original inventor of theforce -pump. Certainly, he devised waterpumps of high efficiency. One of them wasoperated by eight powerful men, and itpumped up water from the Thames atBlackmoor Park and threw it up to the topof Windsor Castle.

To a man of Morland's restless and imagina-tive mind, the question of steam powerwould inevitably arise out of his hand -pumpinventions.

The topic seems to have arisen in tangibleform during Morland's visit to France in1683, for in that year, while resident inFrance, he wrote in French a little Treatiseentitled, " The principles of the new force

Morland's first calculating machine.

of fire invented by Chevalier Morland in1682, and presented to his Most ChristianMajesty in 1683."

This document was never published. It isnow preserved in the British Museum. It iswritten on vellum and consists of thirty-eight pages only. The bulk of the essayconcerns itself with the weights of columnsof water, the thickness of lead for water -pipes, tables of measures, etc., but the finalchapter deals with the subject of steam power.

Morland definitely employed a cylinderand a piston in his engines, although he wasnot the , actual inventor of these devices.He even went so far as to design and constructa primitive form of stuffing box in order toinhibit the escape of steam past his pistonrods.

Patented InventionsBut Morland, apart from employing a

vacuum created by the condensation ofsteam, appears, also, to have at least con-sidered the usefulness of steam pressure.His earliest ideas concerning this subjectcomprised notions for utilising the explosiveforce of gunpowder to drive a piston up alarge cylinder. In the Calendar of StatePapers there is the following entry underthe date, December 11th,,169i :

WARRANT for a GRANT to Sir SamuelMorland of the sole use for 14 years of hisinvention for raising water out of pits, etc.,to a reasonable height, by the force ofpowder and air conjointly.Under the same date, we find, also, the

following entry in the Calendar of StatePapers :-

WARRANT for a GRANT to Sir S.Morland of the sole making of an engineinvented by him for raising water in minesor pits, draining marshes or supplyingbuildings with water.For all his grants and patents, however,

Morland never constructed a true steam -pressure engine. Nevertheless, it was he whofirst began a quantitative study of the proper-ties of steam and, bearing in mind the poorfacilities which existed in his day for exact ex-periment, he obtained some surprisinglyaccurate results in his patient studies of therelationship between the pressure and thevolume of steam.

Other interesting inventions with whichMorland's name is associated comprised amethod of secret writing, a form of penta-graph whereby writing could be copiedmechanically, a mode of removing writingfrom paper, and an apparatus for producingsymmetrical designs by mechanical means.Calculating Machines

One of Morland's more serious inventionswas his calculating machine, which was first

devised in 1666. The Frenchman,Blaise Pascal, had previously con-structed an adding machine, butMorland had no knowledge ofthis device. Hence, his ownmechanical calculator was cer-tainly an original one. Themachine was made of metal andmeasured 4ins. by Sins. by abouttin. in thickness. It had eightdials on its front plate for thecounting of farthings, pence,shillings, units, tens, hundreds,thousands and ten -thousandspounds. Behind the dials werefixed notched discs which engagedadjacent discs and so enabledstraightforward additions to bemade. In this instrument,however, there was no automatic

122

provision for carrying amounts of onedenomination to another, as, for example,converting shillings into pounds. This hadto be done mentally by the operator of themachine.

Another calculating machine devised bySir Samuel Morland multiplied instead ofadded. It could also be employed for theextraction of roots. A further machine ofMorland's essayed to give solutions of trianglesand to evaluate trigonometrical functions.The first two of Morland's calculatingmachines were described in detail in his book," The Description and Uses of Two Arith-metick Instruments," which was publishedin London in 1673. But for all their originalityand their crude ingenuities of construction,Morland's " arithmetick instruments " served,at that time, no utilitarian purpose. Theywere curiosities only, and, as mechanicalcurios, they soon descended into the all -embracing limbo of worldly oblivion.

Experimental Barometer -

Other technical experiments conducted bySir Samuel Morland were concerned withatmospheric pressure. He made a special -form of barometer having a sloping or inclinedtube so that a slight change in atmosphericpressure produced an enhanced movement of

NEWNES PRACTICAL MECHANICS

the mercury within the tube. The device washardly practicable, however, and it soonsuccumbed to better inventions.

Sir Samuel Morland was of too roving andtoo temperamental a disposition to succeedwell with any mechanical project. He showedhis originality and his inventiveness in manydirections, but few of his machines (apartfrom his pumps) had any lasting success.After the death of Charles II, his fortunesprogressively deteriorated. In his later yearshe lived on and even below the abject povertyline, and, to make his distress still more acute,he was stricken withpermanent blind-ness:Yet, in spite ofall this misfortune,Morland stillcherished and nur-tured his inborninterest in mechan-ics ; and, seemingly,he kept his eccentri-cities to the end.

Morland died inthe December of1695, having justattained' the allottedspan of seventyyears. Few noticed.

January, 1943

his' passing, for the fame of Sir Samuel'Morland was spent. But the birth ofsteam power was now nigh, and only tenyears were to elapse before ThomasNewcomen demonstrated his famous" atmospheric " engine, the first practicalmeans of obtaining continuous motive powerfrom the use of steam. But in those ten yearsthe memory of Morland completely dis-appeared. It has only been revived in detailwithin comparatively recent times in conse-quence of the new historical light which isnow being turned upon mechanical inventions.

Another early calculating machine, constructed by the Frenchman, Pascal.

The Steam Car

Fig. 6.-An experimental steam car

STEAM as a motive power for privatecars and light delivery vans has alwaysbeen a possibility and, from the early

days of the White and Stanley cars, has beenthe ultimate aim of a small body of enthusiaststhroughout the country.

The object of this article is not to givedetailed instructions as to how' to build asteam vehicle, or even to convert an existingpetrol vehicle, but rather to lay before thereader a r6sume of what has been done, andwhat is still being done in the hope of pro-viding, for the happier times ahead, a reliableand cheaply produced means of transportwhich would be independent of importedfuels. There is no doubt whatever that sucha vehicle, using home -produced fuel, would,providing it was reliable, be an asset to thecountry and open'up a new era of motoringhistory.

Earlier Objections to SteamIt has frequently been said that the un-

reliability of the earlier attempts killed the

on trial.

The Present and Future Prospects

of Steam Propulsion for Cars

By W. J. ROBERTS

prospects of the steam car, but on looking intothe matter this does not seem to be quite thecase, as a matter of fact all the drawbacksraised by the objectors applied equally to thepetrol car of the same period, they were :Clumsiness and ugliness, the bewilderingconfusion of taps, levels, pressure gauges,etc., and the dirt associated with the wholebusiness.

Stanley EngineWhen we come to examine these objections,

however, they are not so real ; compare, forexample, the Stanley engine,'shown in Fig. r,with any petrol engine of its time, the balancegoes to the steam engine even on the score ofsimplicity alone, and talking of simplicity,consider the White boiler and burner (Fig. 2),a model of simple efficiency.

Space, however, will not permit more than

Fig. r.-Engine of the early Stanley steam car.


2. --The White steam genea passing glance at these " old-timers,"interesting though they may be.

The next attempts at steam vehicles camejust after the close of the last century with theintroduction of two famous names in theheavy vehide world : Sentinel and Foden.The fallacy of the " unreliability " of steamwas exposed by the consistent performanceof these familiar vehicles ; their decline wasnot due to their own characteristics but wasbrought about by the excessive taxation theywere subjected to. During the same periodthe American designers produced a modera-ately successful job in the Doble car, one ofwhich was purchased and run by a womanfilm star !

Recent DevelopmentsDuring the last decade, however, the petrol

car has developed almost to perfection, and,whilst it would not be right to belittle theSuccess of the mass-produced light cars ofrecent years, there comes a phase, however,in the development of any machine, built tocertain principles, when perfection isapproached, and that:period seems to be almostwith us as regards the modern petrol car;thus the time is ripe for the further develop-ment of the steam car.

Fig. 5.-S i d eview (in section)of the Bolsoversteam car engine.

From the mass of dataand facts available, pro-vided by many steam carenthusiasts, it is onlypossible to mention themost interesting ; accord-ingly, the first recentdevelopment of note isthe work of the BolsoverBros., two Yorkshire en-gineers who have beeninterested in the matterover a very long period.Their earlier work con-,sisted of the design ofsteam engines and boilersto adapt the existing carsto steam propulsion, andtwo outstanding engineswere produced. One; aradial, designed to boltdirect to the clutch hour.ing after removal of theI.C. type engine, thusutilising the existing trans-

aror. mission system and otherdetails of the original car. In each casethey had the intention of utilising thepresent radiator as a condenser, the petroltank for carrying water, and the installation ofa boiler under the existing bonnet in place ofthe original engine.

Utilising Existing Petrol EnginesThe system finally evolved by. the Bolsover

Bros. was recently patented, and represents areal step forward. In its essentials it consistsof the conversion of a standard 4 -cylinder carengine to steam by substituting for thestandard cylinder head .a pair of cylindersdesigned for steam operation, and thus theadvantages of the existing engine and trans-mission system are retained. The onlyalteration is the modification of the valvecamshaft drive and re -shaping of the cams tosuit steam power, no reversing' gear is fittedas the existing gearboX provides this. Thediagram, Fig. 3, gives a sectional view of theengine. which is quieter, has greater flexibility,and possesses a. stronger pull at low speeds,cannot be stalled and, most important of all,runs at a fraction of the original cost.

Self-contained EnginesAs an alternative to the above conversion

system the same firm has produced a useful" V " twin compound engine suitable forthe light car or van, rated as 20 h.p. at 2,000r.p.m. with a steam inlet pressure of1,coolb. per sq. in. Sectional views of theengine are given in Figs. 4 and Fig. 4 beingfront and Fig. 5 aside view of thecompleted unit. Itis supplied as a setof castings for thepurchaser to ma-chine and assemble,as also is their four -cylinder radial de-sign. As a matterof interest thephotographs Figs.6 and 7 will aepaystudy ; they arephotographs of astandard petrol carchassis convertedto steam, utilisingan engine from aStanley to h.p.steam car, and a 55h.p. White semi -flash boiler of about35 sq. ft. heatingsurface. Fig . 6shows the car onthe road under test.

Fag. 4.-Cross-section of theBolsover lightsteam car engine.

The Steam GeneratorThe unit which has given most trouble in

steam car design and construction is thesteam generator, or boiler. The earlierboilers suffered from the disadvantage ofslow steam raising and fuel problems. Severaltypes have been designed and tried out andBolsover Bros. have at last given us ananswer to the problem in the Bolsover-Rogersboiler.

Originally two types of boiler were designed,one to burn solid fuel and the other to burn

Fig. 3.-The " Bolsover " conversionsystem.

liquid fuel ; the latter, a very ingeniousarrangement, was capable of raising steamsufficient for, moving away in a matter of

The engine is a 2 -cylinder double-acting compound, 90 degrees, V design.Size of cylinders: H.P. din. bore ; L.P. 21in. bore, by ilk stroke.Engine is rated to develop 20 h.p. at 2,000 r.p.m. with a steam pressure

of 1,5001b. per sq. in.


minutes by simply turning the ignition key.However, in view of the shortage of liquidfuel and necessity to conserve it, this one islikely to be shelved for some considerabletime. The boiler for solid fuel, however, isillustrated in Fig. 8, and the details givenhere are those kindly supplied by the designers.

Under the Bolsover-Rogers patents a cleversystem of hydraulic damper control has beenperfected. That is, when the temperature ofsteam reaches a predetermined .point, roundabout 75o deg. F., water under pressure ismade to flow from a small pressure storagevessel and to act upon a piston which operatesthe damper, very positively closing the latter.This causes the steam temperature to fall below75o deg. F., the water pressure is thenreleased from the damper piston by the actionof the control valve, and the damper is openedagain by means of a spring. This control,which is very sensitive, is governed by amaster thermostat; which, in turn, is influencedby the average temperature of the steamwithin the boiler, thus effectually preventingany over -heating of the boiler coils. Thecontrol is pdsitive and reliable, and it willfunction with certainty without any attention.The temperature of steam is thus kept at thedesired point, and the thermostat can be set,at will, to give steam temperatures at anypoint between 50o and Boo deg. F.

The flow of feed -water to the boiler, and,consequently, the steam pressure maintainedtherein, is regulated by a spring -loaded controlvalve, which keeps the boiler pressure constantwithin close limits.

The boiler is of the " Monotube " forcedcirculation type. The tube assembly con-sists of a series of flat spiral coils in the upperpart of the boiler. _ The feed water enters thetop coil, it is forced down by the action of thefeed pump through the series, and then passesinto a large helical coil which surrounds thefire zone. Steam is generated in the helicalcoil, and is then superheated by passing itthrough several flat spiral coils, which areplaced on top of it. Coke fuel is fed into thefire zone through a firing -chute located onthe top plate of the boiler casing.Final Notes

Owing to the need to conserve fuel, eventhe coal or coke fired boiler will have its fuelproblem, but a suggestion has been made fora method of firing steam car boilers of theflash type, utilising heavy oil obtained fromthe sumps of petrol cars. Every filling stationhas quantities of this which would gladly begiven away ; the problem of filtering andburning it should not prove insurmountable,and although the calorific value is low, thequantity available is sufficient to meritconsideration.

The foregoing is briefly the story of thesteam car in England. That there is a futurefor it is the firm belief of many. If its develop -

Fig. 7-A steam car enthusiast at work on a converted car.

MCM.3101LACAAME

.30

ejector

EMI EL,EICAFAVA

Feed WeerHeating Section

S -.er-heaterSecoon

SteamingCc /s

F g. 8.-Exterior view (left) and- section ofthe Bolsover-Rogers steam plant.

, .

A leading feature of the Bolsover-Rogers steam plant is its use of coal or coke for fuel,which is burned within the steam coils of the boiler, as indicated in the illustration.

ment is carried on with ,the energy and brains and British initiative should notpersistence devoted to its petrol counterpart eventually get a steam car into the productidnthere seems no logical reason why British stage.

British Flying Schools in U.S.ALTHOUGH R.A.F. cadets are no longer

being received in United States ArmyAir Corps schools owing to the expansion ofthe Corps, the flying training schools builtby the R.A.F. in America are carrying on withundiminished vigour.

These British schools are six in number.They were built on virgin sites, some inthe desert, taking from 4o to 6o days fromstart to 'occupation. The staffs consist ofAmerican civilians, with the exception ofan R.A.F. chief instructor, who is also *O.,an administrative officer, a chief groundinstructor squadron leader and two arma-ment N.C.O.s.. The nucleus of the staff wasfound among the instructors of the Americancivil flying schools belonging to the big aircorporations.

America is rich in vast level regionswhere rainfall is low and visibilityhigh. Perfect flying weather, is enjoyed

almost all the yearround. One school is atTerrell, 3o miles fromDallas, Texas. Here thesurroundings are fieldsof rice' and maize.The Miami, Oklahoma,School is set amongrolling grasslandswhere cattle are raisedand zinc is mined.In Arizona there is aschool near Phoenix.Beyond the orangegroyes which surroundthe school buildings arecactus and sage brush,with' a background ofmountains. A riverirrigates the orchards.Perhaps the cadets atClewiston, Florida; arethe most fortunate,for they can enjoyperfect bathing all the

year round, both in the Gulf of Mexico andin the Atlantic. The climate is almost tropical.

R.A.F. StandardThe cadets at these schools are trained

on jhe R.A.F. standard syllabus. Primary,basic and advance flying training is givenduring the course, which includes nightand cross-country flying. A great deal of atten-tion is given to instruments. R.A.F. traineesare also received at United States Navaltraining establishments at Grosse Ile,Detroit, and Pensacola, Florida.

As some return for the hospitality shown toR.A.F. cadets by American authorities, theBritish schools,there are being 'expanded totake in American cadets. An interestingcomparison of methods has resulted from theseexperiments in co -training. R.A.F. officerswho have taken part express the liveliestgratitude to the Americans for their spiritof helpfulness, and the keenness with whichthey have put all available accommodationand experience at our disposal. It is pleasantto record that our cadets have madefriends everywhere, and have proved them-selves the best of ambassadors. The welcomegiven to them by local inhabitants is de-kribed as marvellous, especially so in whatwas formerly regarded as an isolationiststronghold in the Middle West.

WORKSHOP CALCULATIONSTABLES AND FORMULAE

2nd Editionby F. J. CAMM

A handbook dealing with methods of calculation.solution to workshOp problems,' and the rules andformulae necessaryin various workshop processes.It contains all the information a mechanic normally

requires.From all booksellers, 61- net -

by post 6/6 from the publisher,GEORGE NEWNES, LTD. (Book Dept.),Toner House, Southampton Street, W.C.2.


Blohm and ,Voss 141 Monoplane

Merchant Navy ScholarshipsSCHOLARSHIPS for boys who intend

to become Deck Officers in the MerchantNavy are now available as follows :

The Nautical College, Pangbourne, Berks.£70 per annum for three years.

H.M.S. Conway, Tower Buildings, 22,Water Street, Liverpool, 3. £70 per annumfor two years.

H.M.S. Worcester, Greenhithe, Kent. £70per annum for two years.

T.S. Mercury, ITamble, Southampton. £45per atmum for two years.

University College, Southampton. £60per annum for one year.

These have been made possible by thegenerosity of Mr. H. P. Drewry, and suc-cessful applicants will take up their studiesnext autumn.

Candidates mustbe sons of Navigatingor Engine& Officers of the Merchant Navyor R.N.R. who have been killed or seriouslydisabled by enemy action during the war,or who have died during the war while stillin service, but not as the result of enemyaction.

Candidates should be 14-15 years. of ageand should make their application to thePrincipal of any of the establishments namedabove not later than February 6th, 1943.

A sum of £10,000 has been given by Mr.H. P. Drewry, a British merchant and ship -broker, formerly resident in Paris; to providethe above -mentioned scholarships.

Mr. Drewry, when making the gift, ex-pressed a wish to help the Merchant Navywith which his family had been closelconnected for many years.. As a merchantand shipbroker, extensively engaged ininternational shipping trade up to the out-break of war, he is fully aware of theneed for a strong Merehant Navy.

The Luftwaffe has now in service thefirst freak aeroplane of the war. Asshown by these illustrations, thenacelle which houses the crew isplaced on one side of the mainfuselage, and the lop -sided tail -planegives the impression that half of ithas been shot away. The basic reasonfor the design is to obtain anunobstructed view. The engine isprobably a Bramo Fafnir 1,000 h.p.radial, giving a maximum speed of

about 220 m.p.h.

New Insulating" PLASDUCT " is the name given to a

new insulating tubing system recentlyintroduced by The General Electric Co.,Ltd. It has been produced primarily for usein buildings of various types-Nissen huts,emergency hospitals, hostels and camps whereclose -joint tubing or cleat wiring has hithertobeen specified.

Plasduct tubing is constructed of bakelisedpaper and, in addition to being an effectiveinsulator, possesses the following properties :(a) good mechanical strength ; (b) strongresistance to delamination ; (c) resists corro-sion by many chemicals ; (d) highly resistantto moisture ; (e) light weight.

There are only five component parts in thePlasduct system, namely, the tubing, a tubingcoupler, a circular junction box and twocovers. Each unit is matt finished so that, ifdesired, a completedinstallation can be paintedto tone with surrounding decorations.

The tubing is available in 5ft. lengths, andin the following sizes : f in., lin. and tin.diameter. The junction box is i lin. deep

Plasduct junction box, tubing and undrilledfibre cover.

rit'A -OA; Vie if

Tubing Systeminside, 2lin. outside diameter, grin. insidediameter, and is fitted with a fibre base IF in.thick, drilled din. and zin. centres. The boxis so designed that it may be used for mountingswitches, batten -holders, ceiling -roses, or any

similar B.E.S.A. fitting.Easy Fixing

To make a firm, tight joint between junctionbox and tubing it is only necessary to drill ahole of appropriate size with a carpenter'sbrace and steel bit.

Thus, it will be appreciated that by using thejunction box in place of the fitting normallyemployed with metal conduit, a completetubing system can be easily and quicklydevised with an absolute minimum of parts.These features, coupled with the extremesimplicity of installation and, consequently,the comparatively low labour charges involved,make the Plasduct system particularly suitablefor present-day emergencies.

The junction box used as a mounting for,switch and batten -type holder ; and

. (underneath) tubing and .fibre coupler.


War -time Battery Three

The finished receiver with a" Polar " dial ,fitted ready for

aerial test.

T0 satisfy the many demands from ourreaders for a receiver capable ofputting up a good performance on

medium waves, and having a componentspecification of such latiteude that the minimumof difficulty would be experienced in obtainingthe parts, we have produced the designdescribed in detail below.

The conditions imposed naturally limit thevalve arrangement and circuit refinements, soafter giving all considerations our carefulthought, we decided that three valves wouldbe the most satisfactory number to make theset as universal as possible and, to cater forreception in all areas, under average con-ditions, one 7.R.F. stage would be necessary.The circuit, therefore, is as shown below,where it will be seen that it is perfectly straight-forward, and shorn of those refinementswhich would normally have been incorporatedin times when components were easily andquickly obtainable. The question of valvesupply has not been overlooked, and wethink that the valves required, namely t S.G.or H.F. pen., i medium impedance triodeand an economy L.F. pentode, are those mostlikely to be to hand in the majority of con-structors' dens, or obtainable from thosefirms who deal in surplus or second-handcomponents, etc.

Although we give the complete list of thecomponents used in our test receiver, we donot make it a " solus " specification, thusallowing the constructor every latitude in thatdirection, provided, of course, that such partsas are finally used are capable of carrying outthe work for which they were originallydesigned.

I00015 10 v. KIr`

A Medium -wave Receiver of High Efficiency, -Using Coils

Which Can be Made by the ConstructorFor those who have a

well -stocked spares -box,the circuit shown couldbe used as a basis for onehaving a more ambitiousspecification, but thatdepends on requirements.

The CoilsCoil construction can

he a very interestingsubject, particularly sowhen the completed com-ponents are incorporatedin a receiver and experi-ments carried out to securethe highest efficiency. In

this instance, the experimental workhas been. completed ; therefore, evenif you have not attempted coil winding

before you need not fear lack of efficiency.It can be said that these components

form the king -pin of the design, so weadvise every builder of this receiver togo about the coil windingand construction in a carefulmanner, and endeavour tomake a thoroughly soundand neat job. A littleextra care and time devotedto the process will beamply repaid by the im-proved results obtained.

Two coils have to bemade, one for the__ aerialcircuit and the other forthe R.F. coupling. Tosimplify matters, and bear-ing in mind the absenceof long -wave transmissions,the windings are designedto cover only the medium -wave band, so even theveriest beginner should notexperience any difficulty innecessary work.

For the coil formers a length of tubinghaving an external diameter of 'tins. will berequired. We used Paxolin tubing, butebonite, fibre, or even well -dried aqdshellacked cardboard postal tubes can 5eused, provided their walls are stiff enough toallow them to retain their circular shape.The better the insulating properties of theformers the better will be the coils.

For the aerial section, cut off a length of21ins., and for the R.F. transformer 4ins.will be required. Finish off the ends, and thendrill three pin -holes, parallel with and lin.from one edge of the formers. 2

0000

. These form the anchoring holes for thestart of the grid windings, the wire beingthreaded through them two or three times tomake a firm anchoring.

Using 26 S.W.G. \ enamelled wire, wind on-and this applies to each coil --63 (sixty-three) turns, keeping the wire taut, free fromkinks and with each turn tight up against theprevious one. When making the first turnsee that it is parallel, all the way round, withthe edge of the foriner.

Count the turns carefully, and when thewinding is complete, drill three more pin-holes through which the end of the wire isthen fastened, leaving a length of 4ins. forconnections. Now, the start of the winding

The assembly partly wired beforefitting the two coils.

carrying out the

The theoretical circuit, which shows that the design is as. simple as possibleconsistent with high efficiency.

L,!

forms. on each coil, the grid connection,and the finish the earth connection, so thesecan be marked if so desired.

Primary WindingIt will be seen in the theoretical circuit

that a primary winding is required for eachcoil. In the aerial circuit it is connected toform an aerial coupling coil, bulon the R.F.coupling it is used as a normal primaryconnected in the anode circuit of the S.G.valve.

Taking the four -inch length of former first,proceed in the following manner. Cut astrip of Empire cloth or, failing this; smooth -finish stout brown paper, tin. wide and Bins.in length. Wind this firmly round the centreof the winding just completed, and, startingapproximately tin. from the edge of theEmpire cloth, wind on-in the same directionas the other winding -15 turns of 34 S.W.G.,enamelled wire. This calls for a little care,especially the anchoring of the ends of thewinding. There arc various ways of doingthis, and it is possible that the constructormight devise a better scheme than that givenbelow, but do make sure that the ends areanchored securely. Before commencing theavinding cut two strips of Empire cloth lin.wide and tins. in length. Fold them in half,and through the fold of one thread round acouple of times the 34 S.W.G. wire, leavingfour or five inches free. Place the foldedstrip flat on the wide band of Empire cloth,

,January, I Y Lt.) INCVVINCJPRACTICAL MECHANICS 1Z/so that the wire rests in. in from the edge.Alongside it, but with the fold pointing theother way, place the other narrow strip, then,holding both in position with one hand,wind on a complete turn of wire so that itholds them down. It will now be found thatthe rest of the winding can be completed;taking care not to exert too much tension onthe wire, and to see that all turns are adjacent.'When the winding is finished, cut off thewire, leaving a free end of four or five inches,and repeat the method of anchoring the wirethrOugh and round the loop formed by' thesecond folded strip of Empire cloth. Afterthis, grip the ends of the strip and gentlypull them until the loop and wire are tightup against the winding. To _complete, cutoff the spare ends of cloth.

For the aerial coil-i.e., the short former-repeat the whole procedure but, instead ofonly 15 turns, wind on 25 turns of 34 S.W.G.

When the above instructions have beencarried out, the tliird and last winding canbe put on the R.F. transformer, this being toform the reaction circuit.

Reaction WindingThis winding is started half an inch from

the earth end of the grid coil, the wire beinganchored by, the three -hole method alreadydescribed. ' The turns are put on in the

The R.F. transjin.mer in com-pleted form, and before addingprimary and reaction windings.

same direction as the other windings, and thewire used has the same gauge as the primaries,namely, 34 S.W.G. enamelled. For this sec-tion only 19 turns are required.

This now completes all the winding work,so the finishing details can be attended io.

On the aerial coil the bottom end of theprimary and secondary (pr grid coil) haveto be connected to earth, therefore these wirescan be made common to each other on thecoil, this leaving oily one connection to bemade to earth when wiring the coil into theset. Where the end of the grid windingleaves its anchoring holes, strip off its enamelfor a half inch ; cut the wire from the bottom

end of the primary so that it is long enoughto reaeh that point, then, after cleaning it,solder the two together, making sure thatthere is no strain on the finer wire, and thatthe joint is perfectly sound. For fixing thiscoil in position, cut off a length of half -inchsquare wood so that it justfits inside the bottom end ofthe coil former, to which it isanchored by means of a screwon each side passing throughthe walls of the tubing. Thiscompletes the aerial coil.

Finishing the R.F. CoilAfter anchoring the bottom,.

end of the grid winding, takethe free end down through theinside of the former and makeanother anchoring point-twoholes will be sufficient for this-finishing with the end out-side the former. The top endof the reaction winding can alsobe passed down through theinside of the tube and broughtout through the same bottomanchoring holes as, the end ofthe grid winding. These twowires are common to earth, sothey can be soldered togetheras described for the aerial coil.

To allow clearance of thewooden fixing block, theselower anchoring holes mustbe at least -kin. from bottom end of coil former.

The ends of the primary winding shouldbe taken to auxiliary anchoring holes at thetop of the former, an inch being allowed be-tWeen the two fixings. For strength, it isbest to terminate these connections by shortlengths of insulated flexible wire, these beingpassed inside the former, through holes ad-jacent to anchoring points of the fine wires,and, after making a single small knot in them(to take any strain), they can be soldered tothe ends of the primary winding. Thismethod is visible in the illustration showingtAte top view of the completed set and theplan drawing. When this, and the fixing ofthe wooden block in the bottom of the formerhas been done, the R.F. coil is completed.

LIST OF COMPONENTSTwo medium wave coils (see

text).One two -gang .0005 mfd. con-

denser.One .00015 mfd. variable

differential condenser.One .00015 mfd. variable

condenser.One slow-motion dial.Three component mounting

brackets (if panel is notused).

One 0.1 mfd. fixed condenser.One .0001 add, fixed con-

denser.One .04 mfd. fixed condenser.One 2.0 mfd. fixed condenser.One 2 rilegO1131 resistor,

i watt.92! 1 orgohm resistor,

taitt -

One 60,000 ohm resistor,watt.

One screened H.F. choke.One three-point on -off switch.Two four -pin baseboard valve -

holders.One five -pin baseboard valve -

holder.Two terminal strips.Four terminals, A, E, and

L.S. 'positive and negative.Due baseboard 12 x 9ins.One metal screen Ti x 4 ins.One Cossor 210 S.P.T.

(metallised):OnfiesedCo).ssor 210 H.F. (metal-

One Cossor 220 H.P.T.One Exide 2 -volt accumulator.One 120 -volt H.T.

FOlesnb.entetittGliews, tinnedCLWr wire, soldering tags,Systoflex,

Constructing the Set.Unlike our normal designs, we have used

for this receiver a baseboard, thus simplifyingassembly and wiring from the point of viewof visibility and, of course, the beginner.In case this statement appears to contradict

Showing the coils in position and all wiring completed.Note anchoring knots of R.F. transformer primary leads.

the illustrations, which show what might beclassified as a chassis, let us make it quiteclear that all components (bar the on -oftswitch) are mounted on the baseboard, and allthe wiring, except the leads to the switch,are above the baseboard. The two siderunners are purely optional. The switchcould be located elsewhere, and then therunners dispensed with, but we used them toallow an H.T. battery to be housed underthe set, and to give clearance to the controlknob of the particular slow-motion drive weused. Details like this depend solely onindividual requirements.

The baseboard is nin. by 9in., and wascut from a piece of 5 -ply wood. The metalscreen, which is essential, is 7 T,in. by 41in.,

(Continued on page 135)

WIRING DIAGRAM OF WAR -TIME BATTERY THREE

I roll

01We,

INF

2

128 NEWNES 9RACTICAL MECHANICS January, 1943

The Electro ravitic WorldThe Scientific Discoveries of a Century Ago Heralded the Dawn of a New Age. Here are

Presented Reasons for Thinking That Again a Nevy Age is Dawning -

BY the slight movement of a compassneedle, Oersted first demonstrated in1820 a relation between electricity and

magnetism, thereby inaugurating the electro-magnetic world in which we live. In thesubsequent development of electromagnetismmany great pioneers took part, and these,working with unstinted co-operation andresources, after little more than a century ofintensive work, have established electro-magnetism as the greatest achievement of thehuman mind.

In the progressive development of Oersted'sdiscovery we now seem to approach finality,for it is hard to imagine any field left to beexplored of greater potential practical signifi-cance than those already traversed.

Nevertheless, there is such a field, whichwe may call the " Electrogravitic," and itssuccessful exploration will mean to mankindprobably quite -as -much as any of -the greatelectromagnetic discoveries made since 182o.

Faraday's WorkNearly a century ago Faraday attempted to

enter this field, but after considerable workgave up the attempt for various reasons, ill -health being one of them. About 185o heclosed a memorandum concerning this effortwith these words : -

.,

" Here end my trials for the present.The . results are negative. They do notshake my strong feeling of the existenceof a relation, between gravity and elec-tricity, though they give no proof thatsuch a relation exists."Believing that the inspirations of genius are

worth following up, this " strong feeling " ofFaraday'smoved me in 1908 to do some workon this, Ole most obscure problem in the wholeof, physics. Great advances had been madein electrical science since Faraday's time, andI felt that in his failure was no element offinality. It now appears that he could notpossibly have succeeded, for in 185o enoughwas not yet known about electricity, and isnow known only because of Faraday's work.

How to attack the problem was the primarydifficulty, and innumerable failures wererecorded at first. But a form of radiation wasat length found, which quite certainly slightlyaffected weight, even at a distance of loft.from the radiator. But to deal with gravity ona large scale it was felt would make largepower demands, and the methods primarilyemployed were deemed unsuitable to meetthe requirements. Hence, keeping in mind theefficacy of a certain form of radiation, othermethods of generation admitting of the useof unlimited power had to be devised. Again,after innumerable experiments, this also wasfound.

But at once another difficulty arose. Asmall variation of weight (L) could now beproduced at will, but all attempts to increase Lfailed so consistently that this -problem assumedproportions hardly smaller than the first.

Validity of First StepDuring the solar eclipse of 1919 scientists

proved the truth of Einstein's mathematicalprediction that a ray of light would be foundto be deflected in a strong gravity field.

Now we know that electromagnetic effectsare often reversible, and :t thus seemed ajustifiable inference that, if gravity can soaffect electromagnetic radiation, we should beable to find some extremely energetic form ofradiation capable of affecting gravity.

By W. D. VERSCHOYLE

The fact already discovered that radiationwas implicated in L thus received inferentialsupport, but no, light was thrown thereby onthe operative factors. Increase of voltage, andhence of power, certainly made a smalldifference, but only to a point where furtherincrease met with no response from L.Some vital factor still awaited discovery, andmy working theory gave no guidance as toits nature.

Basis of Extended Working TheoryIn a monthly notice of the R.A.S., dated

December, 1923, dealing with " Internal

doubtless towards an upper limit still a longway off. With the apparatus available anincrease of nearly 2,500 per cent. was observed,as a first small step towards what wastheoretically possible. The ultimate limit ofgravitic response is an unknown quantity,and is certainly not reached in terrestrialexperience. One sentence in Eddington's" The Nature of the Physical World " showsthis : " . . . in the Companion of Sirius thedensity is about a ton to the cubic inch."This is usually attributed to a super -ionisation process ; but with the new ideasmay also be explained as an actual increase of

An artist's impression of a heavily -armed aerial tank of the future. Note the absenceof wings- and elevator. .

Motions in Spiral Nebular," Sir James Jeanswrote :

" It is at least conceivable that a slightstep from a gravitational force M r2 in thedirection of a force v2;r might be found toprovide explanations of some of theunsolved enigmas of the solar system, suchas the moon's motion in longitude, Bode'slaw, and the circularity of planetaryorbits."Now this is a pregnant suggestion, for

whilst a vyr gravity will produce ,but smalldifferentiation in the internal motions of aspiral nebula, at intra-atomic velocities anddistances of the order of to -13 cm. this forcebecomes of tremendous importance, providedthat we can agree that the term portion ofmatter, as used in Newton's law of gravitation,is applicable to every particle entering intoatomic constitution.

But, even so, it was felt that a v2,r forcecould 'not act at all, in a nebula or anywhereelse, without a fundamental change in ourideas regarding the elementary particle andgravity itself ; and, in 1930, what were deemedsuitable changes were incorporated in myworking theory, together with a dependentheuristic concept of the missing factor, andto bring this into operation alteratibns weremade in my apparatus.

The effect on L was immediate. Its valuerose as the new factor value was- increased,following a straight-line /elation, verging

gravity output from a small body, at what wemight call a compound logarithmic rate, underthe conditions obtaining in White Dwarfstars.

Validity of New IdeasIn 1936 came tome welcome evidence as to

the validity of the basic changes on whichthis progress was founded.

In the Physical Review (U.S.A.) of Novem-ber, 1936, is announced the discovery, at theCarnegie Institution of Washington, D.C., of" a new attractive force overpowering theCoulomb repulsion " between the ultimateparticles whereof .the atomic nucleus is com-posed, when the distance between theseparticles is of the order. of to-13cm. Theannouncement concludes :

" It thus appears that a real beginninghas been made towards an accurate andintimate knowledge of the forces whichbind together the `primary particles' intothe heavier nuclit so important in thestructure and energetics of the materialuniverse. 'Now to make this " new attractive force "

operative and explicable requires exactly thesame changes in our basic ideas as does Jeans'v2,r gravity, and also- the increment of Lin my experiments, and it thus seems certainthat the same force is implicated in each and,furthermore, that the changes may be foundgenerally useful, both where the constitution

THE lot of the inventor has often beenhard, in that the successful applicationof inventions depended on better

material and more accurate workmanshipthan that available at the time. Thus.practical improvements have often laggedbehind the ideas of forward -looking men.The history of the steam, engine illustratesthis theme. The introduction of the com-pound engine was premature in that notuntil many years after could boilers be con-structed to withstand the higher pressuresteam necessary for the successful applicationof the idea of compounding. The earlyengines of Newcomen and Watt were verydependent upon the crude facilities availablein those days. The earliest of the Newcomenengines had brass cylinders as it was im-possible to procure cylinders of cast iron, thestate of the foundry industry being verybackward. Whilst foundry work was in itsinfancy, machining was unknown ! Thefirst cylinders that were successfully cast wereoften out of truth with regard to the bore,and it is recorded that Mathew Boulton,when making the - early Watt engines atSoho, wrote to James Watt who was still inEdinburgh, " My dear friend, congratulateme, I have just succeeded in making acylinder nowhere more than a quarter ofan inch out of truth."

Cylinder Boring DifficultiesThe cylinders for the early Newcomen

engines would not be machined in a boringmill or lathe, but were cast as near round aspossible, and finished by the followingmethod. The cylinder was laid on its sidein the yard and a block of lead, about two tothree hundredweights, was cast inside it ;to this was added about a bucketful ofemery and oil. Then two gangs of menpulled the block backwards and forwards,by means of chains, until they had scoured'the cylinder smooth. The cylinder wasthen turned round a little on the ground, andanother portion was 4toured smooth. Whenit is considered by what means the earlyengineers produced their cylinders --often

January, 1943

of matter is under consideration, and wheregravitic effects are suspected to be abnormal.

In the progress towards its far -distanttheoretic limit, electrogravitism enters theworld of practical things in the manner brieflyoutlined on page 138 of the February issueof PRACTICAL MECHANICS.

An electrogravitic age is surely dawning, itsfoundation such as I adunibrated in 1932(The Soul of an Atom):

" The structural plans of the atom andthe solar system are identical; each is heldtogether by the same universal force ; thesame mechanical principle modulates andsensitises their physical relations ; and thus,at different ends of the scale of nature, theyexemplify the uniformity of physicalprocesses which have entered into theconstruction alike of the great and the smallthings of the universe."

AcademicAgainst this structural plan and electro-

gravitism generally comes the whole force ofRelativity Theory. Inertial and -gravitationalmass are inseparable. The first is certainlythere, and must be incorporated in the theory,but it simplifies matters to drop gravity.Hence, there is no such force as gravity ; thereis only a geometric curvature of space-time.

Again, in Einstein's space-time continuum,


Reimannian geometry or Weyl's extension ofit, is no very secure place for electromagneticphenomena, even though these unquestionablyform a most important part of worldexperience.

Thus, at two points the fundamental con-cepts of electrogravitism differ from Relatival-it must have gravity, and is itself an exten-sion or refinement of electromagnetism.Also, it embodies the belief that through theelectrical theory of material constitution noenduring picture of our world can be obtained.It stresses the importance of structural detail,no less for the electron, than for the atom,the solar system, or the universe ; and thenthrough defining tentatively an electronicstructure, it finds a real physical differencebetween inertial and gravitic mass, gives SirJames Jeans his v2 r gravity, accounts for,and even anticipates, the Washington newattractive force, offers a new explanation ofthe "Coulomb repulsion,"" and hopes to buildon a strictly experimentalL-foundation a newand inspi ring world, a world of new expe-rience-the Electrogravitic World.

The Electrogravitic WorldWorld conditions are subject to no in-

fluence more productive of change than rapidtransportation, and in the electrograviticworld this influence will reach the limiting

129

possibility of speed. What will it be?800 m.p.h., who can say ?A day -return ticket to New York or otherequidistant centre will be bought at the ticketoffice with the same unconcern as at presentto Brighton. A long-distance move of a tonof freight by aeromotor will cost about thesame as on a railway at present. More powerwill have to be applied, but it will be for amuch shorter time. Ease of departure andlanding will cause to vanish the inaccessibilityof the poles, the mountain top, and the junglefastnesses of the equator. Internationalboundaries will have no more thangeographical significance, and freer inter-course will lead to better understanding, andto a less barbaric adjustment of internationaldifferences than the present totalitarian callto arms.

And from the slight movement of a compassneedle, obseryed by Oersted in 182o, all thisfollows.

It is worth mentioning that work on thisproblem was by no means continuous between1908 and the present. The heavy cost of theexperiments had to be financed, and this wasdone quite largely by development and saleof sundry inventions. This and other businesginvolved about twenty trips across theAtlantic, and two round the world duringthat time.

Practical Engineering in Bygone DaysSome of the Difficulties Which Had to be Overcome

By T. R. HARRIS

four feet in diameter and ten feet long-itis a wonder that their engines were as goodas they were. Necessity, always the motherof invention, soon demanded some betterway for preparing cylinders, and the boringmill followed. But here again perfectionwas difficult to obtain. The CoalbrookdaleWorks were pioneers in the casting andboring of cylinders, and as these increasedin size difficulty. began to be experiencedfrom the frequent breakage of the boringbars. It was desired in 1734 by the managingpartner, Richard Ford, to have for thispurpose " a wrought iron spindle, 12ft. longand full Sin. in diameter ; one end to beleft square for t8in. and ye other end to beleft square for 6in., and the remaining 'oft.be left round, but to be as true as may be, andto be made of right tuff iron and right sound."This was ordered from an anchor smith inBristol, and supplied at a cost of £26 Ios. od.in September, 1734. Another was obtainedin 1745, 15 cwt. 3 qr. 15 lb. at 8d. per lb.,£21 19s. 4d. From 1755 to 1765 JamesBrindley,the famous engineer,was frequentlyat Coalbrobkdale, and superintended themanufacture of a large engine sent toNewcastle -on -Tyne for the Walker Coal Co.in 1763. The cylinder was loft. long and74in. in diameter, and was said to be thelargest that had been sent to that district.It was also stated that the " bore was turnedperfectly round and well polished " and"the whole a complete and noble piece ofwork."

Introduction of the Boring BarThe accurate boring of large cylinders was

however still a source of anxiety. In 1751it was stated, " The 54in. cylinder for LordWard having been examined, was found to betrue and exactly bored, viz., within 1/16in.in all the working parts." In 1776 JamesWatt wrote to James Smeaton, " Mr.Wilkinson has improved the art of boringcylinders, so that I promise upon a 72in.cylinder being not further distant fromabsolute truth than the thickness of a thinsixpence in the worst part." This reference

is to John Wilkinson of Bersham, nea_Wrexham, who in 1775 contrived a newmachine for more accurately boring the insideof cylinders. A straight bar was fixed in theaxis of the cylinder which was made torevolve slowly around it, while a slidingcutter was caused to travel along the centralstationary bar. On the expiration of Watt'spatent in 1800 other engineers commencedthe manufacture of engines. Among thesewas Mathew Murray of Leeds, who becamea serious rival to the Soho firm of Boultonand Watt. A letter written by James Watt,Jun., from Leeds on June 15th, 1802, des-cribes Murray's Works. In the course ofthis letter occurs the following : " His(Murray's) cutter block is pushed forwardupon the boring rod by an endless screw,which, or some similar contrivance, we mustadopt,looth to guard against the negligenceof the borer and to save part of his wages."

" Casting Brass Burrs "A,Thus the early engineers hot only designed

and built their engines but had to deviseand construct their own tools and overcomenumerous difficulties. Not only were endlessscrews difficult to make-being hand cut-but the nuts or, as they were called, " burrsin which the screw worked also presenteddifficulties. These were mostly of brass andcast around the screw. A quotation from apublication of 1835 is a further illustration." Casting Brass Burrs. The usual method ofaccomplishing this object, is to place thescrew in a mould of the required form, andto cast the brass about it, by which meansa very perfect burr may be produced, but thereis frequently great difficulty in removing itfrom the screw. To avoid this a lead burris cast in the usual way (which may be easilytaken off) and used as a box for the formationof a sand core. After the box is filled, it issubjected for some hours to the heat of thedrying stove, and when its contents arefound to be perfectly free from moisture, thewhole is plunged into the melted lead, whichrobs the core of its casing, and renders thesand copy fit for use instead of the original."


Fig. 1-77teCompleted pump,and stand on apail of water,and ready foraction. Flexiblemetallic tubing isused for the

delivery hose.

IN designing the pump shown in theaccompanying illustrations, the writerhad in mind an inexpensive and light

appliance, which could be constructed in asmall home workshop, and which would bea satisfactory substitute for a stirrup pump.

Using a plain nozzle, the finished pumpcan, with little effort, project a &in. jetof water a distance of zoft., and will emptya pail of water (2 gallons) in three minutes.

It will be seen, with reference to Fig. r,and the illustration on the cover of this issue,that the pump is mounted on a wooden standwhich conveniently rests on an ordinaryhousehold pail. When using the pump theleft foot of the operator rests on the baseboard,the right hand working the pump lever, andthe left hand manipulating the nozzle.When dealing with explosive incendiarybombs two men would, of course, be required

*to handle the pump and nozzle.

General ConsiderationsThere are several novel features embodied

in the pump. For instance, an ordinarybrass garden syringe sawn in half providedthe two pump barrels. Hard red rubber tapwashers are used for the pump valves, andparts of a brass cycle -pump barrel are usedfor the cylindrical valve chambers. A copperscreening can taken off an old wirelesscoil forms the body of the air vessel.

Constructional DetailsThe first parts taken in hand were the two

valve chamb;rs which, together with thevalves; form the " heart " of the pimp.

Two 1 ',in. lengths of sin. outside diameterbrass tubing were cut from an old cyclepump, barrel, and the endS filed up square.'In one side of each tube, midway from theends, a ,^,, in: hole 'is drilled. In each holeis soldered a brass bush with a in.- internalthread. Next, two discs of kin. thicksheet brass were cut out as shown in Fig. 3,

MakinA a DuplexConstructional Details for a

A.R.P. Work and

after being markedout with compasses.The two tin. holeswere made with theaid of a carpenter'sbit. The holes weremade slightly undersize, and filed sothat the tubes werea push fit. Afterpressing these inplace so that theends projectedthe joints were wellsoldered. Fig. 4shows this part ofthe work completed.

Valve Seatings For making the

valve seatings, astrip of s6 gaugehard flat, sheetbrass sin. wide wastaken, and on thecentre line fourcircles were scribed(Fig. 5) of the same"dia"meter as theinside of the valvechambers. Fromthe same centresfour more circles

were scribed having a diameter of -kin.These smaller circles were then dividedinto six equal parts by scribing light linesthrough the centres, and the points of inter-section were centre -punched and -kin. holesdrilled through. A Ain. diameter hole isdrilled through each of the four centres andtapped with a kin. thread.

The brass strip is then divided into fourparts by cutting through with a cold chiselon the lines marked " a," using an olddomestic flat iron as an anvil (this method ismuch quicker than using a hacksaw). After

Siwle of /nays

Fig. 2.-Front, and. part -sectioned side elevations of pump, A sectionplungers is shown in the inset.

By A. J. BUDD

cutting off the corners with the cold chisel,each piece in turn is placed between lead clamsin a vice, and carefully filed down to thescribed circle. Each disc is then rubbedover the face of a smooth -cut hie to removeall burrs, and each disc finally filed round the

1 *-

. 2stFig. 3.-Details of valve chambers and support-

ing plate.

edge till it was a push fit in the end of thevalve chamber.

Valves and GuidesAs previously mentioned the valves consist

of rubber tap washers, and they should be lin.diameter and at least min. thick. Whenpurchased these will be found to have acentral hole a little over kin. diameter whichis just right for the purpose.

The valve guides consist of the shanks ofplated screw -hooks, of the pattgrn shown inFig. 6. Make sure when obtaining these

one of the. pump


Fire PumpSmall Hand -pump Suitable forOther Purposeshooks that the shanks are gin. diameter.Hold the screwed end of each hook in turn,in a vice (between lead clams, of course)and with a hacksaw cut off the turned -up end.File the end square and then, with a screw -plate, cut a 1,in. thread on the end for adistance of about gin. Now reverse theshank in the vice, and cut off the screwedportion to within gin, of the flange, as indi-cated in the sketch. File the end square,and then file two flats on opposite sides of theprojecting piece.

As the two suction valves ark inside totevalve -chambers, the former, with their guidlis,have to be placed in position before theirseatings are soldered in place.. After placingthe valves on the guides, screw the ends intothe central holes of the two seatings by

Fig. 7.-Part sectional view of valve chambersand outer casing.

gripping the squared ends in a vice. Fig. 4shows the finished seatings and guides, oneof the rubber valves ,being shown in position.

Press the two suction valve seatings inplace to within ;;;in. of the ends of thevalve chambers, and then solder in place.This must be carefully done so as not to allowany solder to run into the holes in the valveseating. The seatings for, the delivery valvescan now be soldered in place, and the guides,with the valves in place, screwed in. Aftersoldering in each valve seating it would be aswell to cool the part in cold water beforeallowing the rubber valves to come in contactwith them.

Valve Chamber CasingIt will be seen, with reference to. Figs.

7 and 8, that the valve chamber casing con-sists of three parts-the body and two ends.In the model illustrated, the body is made

from a potted meattin, while thedomed ends are ofdished block tin.The body isinside diameter andzin. deep. As analternative, flatdished brass stampsings could, withadvantage, be usedfor these ends, asshown in the draw-ings, Figs. 2 and 7.

Two 19, -in. diam-eter holes, diame-trically oppositeeach other, arebored .through thesides of the bodyto allow the endsof the connectingtubes to be screwedinto the valvecihambers, whenthese are assembled.

Through The centres of the domed endsgin. holes afe bored to take gin. screwedbushes, which form the suction and deliveryconnections. These bushes are well solderedto the ends on the inside.

Before assembling the valve chambers andcasing, well clean the inside edges of thelatter with fine emery cloth, and also the

ho/es

Sew off here

Friedridr

Screwed t

edges of the circular plates which supportthe valve chambers. Press the valve chambersin place inside the casing so that the circular

Fig. 4.-Valve chambers, supporting plates, and valve seatings andguides.

Fig. 5. - Markingout brass strip formaking valve

seatings.Fig. 6 (left).-Details

of valve guides.

Fig. View of the assembledpump, mounted on the backboard.

(Pump lever omitted.)

plates are equidistant from the ends of theformer, and alsb make sure that the screwedbushes coincide with the holes in the sideof the casing. When any necessary adjust-ments have been made the joints hetweenthe circular supporting discs and the inside

of the casing can be soldered.The next step is to well solder the

dished ends in position, removingany superfluous solder after coolingin cold water.

Pump BarrelsThe two pump barrels, which are of

brass, 61in. long and r?,in. outsidediameter, were cut from a disused

garden syringe, and the ends filed square.At a distance of gin. from one end ofeach barrel gin. holes are drilled, into whichthe ends, of the brass connecting tubes aresoldered. These tubes, which are Sin.long, have a thread cut on the other endsfor screwing into the bushes in the valve,chambers. The bottom ends of the pumpbarrels are closed with discs of sheet bras

thick, soldered in place.

Fig. 8.-The body and ends of the valve chantb..;rcasing.'

4

132

a

i--

Fig. 9.-Connecting-rod and eid

Plungers and Connecting RodsThe plunger taken from the garden syringe

was used for one pump barrel, and a similarplunger to match it was made as shown inthe detail sketch in Fig. 2. Two stout tinlids were obtained, a good sliding fit in thepump barrel, and a -kin. hole drilled' in thecentre of each. Three brass washers, T.in.diameter and lin. thick, are placed betweenthe tin lids and the whole clamped togetherwith a brass bolt, On. long, underthe head. A strip of -11, in. sheet brass,bent to a U -shape, is drilled and tapped toscrew on to the end of the bolt, as shown.A ;,in. hole is drilled through the upturnedends for taking the connecting pin. Afterscrewing it on tightly, the U-shaped pieCe issoldered to the bolt and to the top of theplunger. Details of one of the plungers aregiven in the inset in Fig. 2.

The two connecting rods are of brightmild steel, 4in. long and screwed at . eachend for a distance of in. On one end ofeach connecting rod is screwed a V-shapedpiece, A (Fig. 9), which is attached to thepump handle, the other end of each rodbeing screwed into smaller U-shaped pieces(B), which are attached to the plungers.

The larger parts (A) are bent to shapefrom pieces of 'in. sheet brass, in. wideand 4in. long, after marking out and drillingthe holes. A brasS disc, in. thick, issoldered to the underside of each U -Piece,and the central holes continued throughand then tapped to receive the screwed ends of

J-7:41

22t3.-Details of metal plates for

forming the trunnion bearings for the.pump lever.

the connecting Tods, which should be a tightfit. The smaller parts (B) are made in thesame way, and discs soldered on for thickeningpurposes. These ends are attached to theplunger lugs with in. bolts and nuts.

Backboard and FootrestAt this stage it is as well to prepare the

backboard on which the pump parts arefixed. For this purpose a piece of deal willbe required ictin. long, 9in. wide, and in.thick. Plane this on both sides, mark thecentre line, and pencil in the outline of the topedge (see Fig. it). With a hand -saw andcoping saw cut this edge to the requiredcontour, and smooth over with a rasp and


glass-paper. A part has to be cut away in thebottom centre of the board, as at C, to accom-modate the back of the valve -chamber casing.A shallow concave recess, D, is also made toallow for the back Of the air vessel.

The footrest, which is t5in. long, and yin.wide, is made of Ain. wood. In the centreof the front edge, a semicircular part is cutaway to take the lower end of the valve -chamber casing. The footrest is fixed to thebackboard with four brass countersunk screws,driven in from underneath, as shown inFig. 2. Two iron brackets are also screwedto the backboard andfootrest, at a distanceoft in. from the endsof the backboard.Before finally fixingthe footrest and back-board together itwould be advisableto assemble the pumpparts and screw thepump barrels to thebackboard. Fourclamping strips, each44in. long, are cutfrom in. by in.sheet brass, and holesdrilled in the ends totake -lin. copperedwood -screws in.long. These stripsare then bent to aU -shape to fit thepump barrel, the end

k "41

Fig.

January, 19 43

In assembling these parts the right-angledpiece is first screwed to the top of the back-board with two lin. round -headed wood -screws. It is also bolted to another angle piece,21in. long, which in tuirn is screwed to thebackboard. The tin. strip is fixed to the backof the board with a single screw, and is alsobolted to a small angle -piece, tin. long,which, in turn, is bolted to the base of themain angle bracket. The head of this boltis countersunk. This method of building upthe bearing brackets for the pump lever..results in a very strong and rigid fitment. The.

C

Ei.-Front view. of backboard, giving dimensions.

Fig. to.-The finished connecting -rods and U-shaped ends.

of the strips being also bent atright angles to form feet for screw-ing to the backboard, as shown inFigs. 2 and 52.

Bearings for Pump LeverThe next parts to claim attention

are the metal plates for formingtrunnion bearings for the puMplever. Aluminium sheet tin. thickis used for these parts, which aremarked out and finished to thedimensions given in Fig. t3. .Theright-angled plate is bent to shapeby holding it in a vice andhammering the projecting part

- over till the correct angle is formed. Holesdiameter are drilled where indicated

for the fixing bolts and screws, the tin. holesin the top ends being for the .pump levershaft.

drawings, Fig. 2, showclearly how the partsare positioned, d andscrewed and boltedtogether.

Pump LeverThe pump lever,

shown in Fig. 14, isplaned to the shaperequired, from a pieceof hardwood, 2ft. 4in.long, tin. wide, and

in. thick. Three holesare drilled through onthe centre line, thecentre hole being bin.in diameter and theother two each lin.diameter. A threaded

brass bush, tin. long, and with a pin. centralhole, is screwed into the hole in the lever,and a thin nut is screwed up tightly on theprojecting end. The two smaller holes arebushed with pieces of thick brass tube, abare lin. long, having an inside diameter of

inThe corners of the lever at the handle

end are chamfered for a distance of 4in.,as indicated, to make it more comfortabletOr the hand. .

Air VesselAs previously mentioned, the air vessel

is made from a copper screening can, 21in.dlameter, taken from a disused wireless coil.The bottom of the vessel consists of part ofanother screening can of slightly smallerdiameter, and this is well soldered in place,after having a central hole drilled through it,and a ;in. threaded brass nipple soldered in

2'4"

4.-Side elevation and plan of pump lever.

DUE to the high horsepower developedby modern aero-engines the problemof starting has been greatly increased.

The force required to turn high-poweredengines renders the use of some form of aux-iliary starting mechanism essential. Enginesof up to approximately 200 horsepower maybe started by hand swinging the propeller,but power units developing more than thisfigure are impossible to start, without mech-anical assistance. The main disadvantageincurred by fitting a self-starter is the factthat the engine weight is increased, and thusthe amount of payload that may be carriedby the aircraft is decreased. The size ofthe starter is limited by the space availableand this factor affects their design - to aconsiderable degree. The various methodsof starting and the equipment required willnow be described.Hand Swinging

The propeller hand swinging method is asfollows : The carburettor is flooded and theengine primed with the magneto switches inthe off position. The engine is then turnedover with the throttle slightly open, followedby switching on the hand -starting magneto,opening the throttle, pulling the airscrewover compression as quickly as possible andat the same time turning the hand magneto.When the engine fires, switch off the startingmagneto and switch on the main magnetos.

- The function of the auxiliary magneto is asfollows : The main magnetos do not operateefficiently at low turning speeds and poorsparks are produced. By fitting a handturned magneto a satisfactory -stream ofsparks may be obtained, the current beingdistributed to the correct sparking plugs byMeans of the main magnetos' distributor.Hucks Starter

An improvement on the hand swingingmethod is the Hucks starter. This consistsof an adjustable shaft mounted on a frame-work attached to a standard motor -car chassis.The shaft is driven by the car engine and maybe connected to the propeller boss by meansof a dog, thus revolving the crankshaft untilthe engine fires. The- dogs are designed soas to automatically disengage when the enginestarts. The disadvantages of this system,which is not used very much at the presenttime, are the facts that it is impracticable forlarge aircraft whose engines are mountedhigh above ground level, and that the startermay not be available at every landing ground.

Modern starters may be divided into fourclasses :

t. Hand driven starters.2. Electrically driven starters.3. Gas starters.4. Cartridge starters.

January, 19 43

This nipple screws into one end of a tin.brass T -piece, the other end of which is con-nected to the threaded nipple on top of thevalve -chamber casing. The centre part ofthe T -piece forms the delivery connection ofthe pump, and to this is connected one end ofa length of flexible metallic hose, to the otherend of which a brass nozzle, having a ,din.bore, is connected.

The suction pipe consists of a piece of redrubber tubing, one end of 'which is bound

.to the suction nipple of the pump bymeans of a few turns of enamelled copper wire.


Testing and FinishingWhen finally assembling the pump parts, a

little red lead or paint should be smeared onall the threaded connections to ensure air- andwater -tight joints when these parts are screwedtogether. After screwing down the pumpbarrels, and making any necessary adjustments,fit the pump lever in position, tighten up thehuts, and apply a little lubricating oil to thepivot bolts, and also to the plungers. Thepump is then ready for testing. -

Finally, wipe the pump and stand with aclean rag, and unscrew the pump barrels,

133

When quite dry, the backboard and footrestcan be given two coats of hard -gloss paint,allowing the first coat to dry thoroughly before.applying the second coat. The pump lever,valve -chamber casing, and the bands round thepump barrels are painted with bakelite paint-pillar -box red. The backboard and footrestare painted in dark green.

After the painted parts are allowed todry, the pump can be assembled again andit is then ready for use. -

Give the pump a try -out occasionally to en-sure the valves being in good working condition.

Aem-enAine Starting EquipmentThe Various Systems Used on Modern Aircraft

By T. E. G. BOWDEN, M.I.E.T.

Hand -operated StarterTaking the first of these various types, i.e.,

the hand -operated starter, two alternativedesigns are available, each with their ownadvantages and disadvantages, the inertiatype, and the direct turning type. The hand -driven inertia starter, illustrated in Fig. r,consists of a small but heavy flywheel whichis rotated by means of a handle and gearwheels. The energy stored when the flywheel

Attachment flan

flywheel

Detachablehandle

Engine

"inertiastarter \Se,-tmg

Jaw

Fig. 1.-Diagram of. the hand -driveninertia starter.

is rotating rapidly is transferred to the enginecrankshaft by a system of gears and a clutch.When the rate of rotation is approximately52,000 r.p.m. the clutch is engaged and theengine turned at approximately 8o r.p.m.The time taken to gain the required revolutionsis approximately 3o seconds and the numberof revolutions turned through by the engineis one or two. A safety ratchet to preventdamage should the engine backfire, and aslipping clutch which automatically dis-engages the starter when the engine fires,are incorporated. The clutch is usually ofthe spring loaded type. The speed of theflywheel ivy be judged by the sound causedby its high rate of rotation. A drive to the

Battery

Soleno;dswitch

Booster

Fig. z.-A typical circuit for an electrically -operated starter.

Coc,kpitSWAcn

Starter-,

ro distributor

booster magneto is usually incorporated to facilitate starting.

The direct turning starter consists of ahandle connected to the engine crankshaftby means of a worm and gear wheel mechan-ism. The gear ratio must be sufficiently lowto allow the engine to be turned over by amechanic of ordinary strength. A typicalratio is to to I. As in the case of the inertiastarter, a clutch and ratchet is incorporated.Electrically -operated Starters

Electric starters may be either of the directcranking or the inertia type and operate in asimilar manner to the hand -operated starterdescribed above. The electric motor takesthe place of the manually operated handle,thus saving much physical labour. Shouldthe batteries run down and thus render theelectric motor useless it is usual to providethe alternative hand turning mechanism tobe used in case of emergency or to conservethe batteries. The disadvantage is of coursethe increased weight involved. The timetaken to reach the required revolutions in theinertia type is reduced to approximately 7seconds by using an electric starter.

In order to save weight which would beincurred by running heavy cables (capableof taking the current) to the pilot's cockpitfrom the starter and battery, a solenoid switchis installed requiring only light cable to com-plete the circuit when the starter is required.A diagram illustrating a typical circuit isshown in .Fig. 2. The solenoid requiresonly approximately 5o watts and eliminatesthe danger of transmitting a high amperagethrough considerable distances. The switchthat closes the solenoid circuit is generally ofthe push-pull type, i.e., the switch is pushedin to start the electric motor and pulled toengage the starter to the engine when therequired speed has been attained.

The main disadvantage of the electrically -operated starter is the limited capacity ofthe battery. The size and weight must bekept as small as possible, and thus great careis necessary to avoid running the batterydown, especially in cold weather. A commonmethod used to partly overcome this dis-advantage is to employ an external batteryfor 'starting the engines. The battery ismounted on a trolley and plugged into theaircraft at a convenient position,*and thus thedrain on the aircraft's batteries is reduced.By using a special plug the aircraft's circuitis automatically broken when the externalsocket is plugged into the connection.

The batteries used are generally of the 4oor 25 ampere hours type, and are mountedso that inspection or replacement is as easyas possible. Both 12 and 24 volt systems arein use at the present time and various types

-134 NEWNES PRACTICAL MECHANICS January, 1943

of generators are mounted on the engine tocharge the batteries. A typical generatorrunning at 5,000 r.p.m. develops t,000 wattsat 24 volts. If the aircraft is of the aerobatictype non -spillable batteries must be used.

A booster coil is fitted which is brought intooperation when the electric motor is switchedon, and is automatically switched off whenthe engine fires and the starter is disengaged.

Electrically driven starters require verylittle maintenance. The brushes should beexamined. and the battery kept charged. Thelevel of electrolyte must be checked and ifnecessary the battery topped up with distilledwater. It is important that the cable connec-tions should be satisfactory. Practically nolubrication is required and care is necessarywhen applying oil or grease, as damage maybe caused if the manufacturer's instructionsare not adhered to.

Gas -starter SystemA gas -starter system is illustrated diagram-

matically in Fig. 3. The method of operationis as follows. Air passes from a storage bottle,is mixed with petrol and distributed to thecylinders in their correct firing order. Thecombustible mixture is fired by means of ahand starter magneto and thus the crankshaftis turned until the engine runs on its ownignition and induction systems.

The air is stored in a steel bottle at a pressureof zoolb. per square inch. An engine -drivenair compressor is often used, but alternativesources of supply are hand or foot pumps.One filling will normally be sufficient for fiveor six starts. A small motor -driven compressormounted on a trolley is usually available forcharging the bottle at all main airports.

The compressed air flows from the con-tainer, through the control cock, via a presscock to the atomiser. The press cock maybe operated by the pilot's hand or foot,

to ak compressor"

Co pressed sir bottle

Assmiser

Frain pipe

DistributorFig.

Press cock

aIND

Primmg pump(Auxiliary)

Frompetroltank

Ts

.an kTo cylinders

3. -The gas -starter system.

whichever is the most convenient, and itspurpose is to control the amount of air pasSedto the cylinders. The atomiser's function issimilar to that of a carburettor, i.e., thesupplying of a combustible mixture. Petrolis supplied to the atomiser by means of apriming pump or, if the supply tank is situatedat a higher level, by gravity. Excess petrolis drained by means of the cock fitted at theloiver end of the atomiser. The compressedair flowing past the jet, which is situated ina venturi, draws petrol from the atomiserin the form of a spray which passes along thepipe line to the distributor.

The distributor, as its name implies,distributes the combustible mixture to thevarious cylinders in the correct sequence.Non -return valves are installed in the pipelines leading to the cylinders to prevent themixture flowing back.

The actual procedure when starting is asfollows. The drain cock fitted to the atomiseris opened and the reservoir filled with petrol

by means of the priming pump until petrolflows from the drain pipe. The cock is thenclosed and the main fuel supply cock turnedto the on position. Following these opera-tions the induction system is primed in theusual manner and the cock controlling theflow of compressed air placed in the onposition. The hand -starter magneto is thenrotated and the press cock depressed. Whenthe engine starts up the cock is released andthe main ignition switched on.

Exhaust pipe

Filing switch

Combustionchamber

Engine

Fig. 4.-The cartridge starter.

A very efficient form of starter is thecartridge starter, which is illustrated in Fig. 4.An explosive cartridge is placed in a breechand fired (usually electrically). The gasesproduced travel along a pipe to a cylinder.containing a piston. When the piston isforced along the cylinder by the pressureresulting from the expanding gas the linear

Breech

motion is transformed into rotary motion bymeans of a screwed sleeve. This rotarymotion is utilised to turn the engine overseveral times. An exhaust valve opens whenthe piston has travelled a certain distance andthegas discharged. Due to the high pressuresreached, a safety disc is fitted which collapseswhen the safe pressure is exceeded.

A magazine is usually fitted so,that approxi-mately half a dozen cartridges are available.Different cartridges with varying quantitiesof explosive are available for starting upvarious engines in varying climates.

A variation of the above system is that inwhich the gases produced when the cartridgeis fired are led direct to the cylinders, thusforcing the crankshaft to rotate.

Summing up the methods of startingwhich have been described, it will be seenthat there are eight methods, i.e., handswinging, Hucks starter, hand inertia, handdirect, electric inertia, electric direct, gas,and cartridge starters. Each one of thesesystems has its own disadvantages andadvantages, and when deciding which one toemploy several factors should be considered.For low -powered engines an auxiliary starter,is not generally required. The advantages ofthe inertia starter are as f9llows : the engineis rotated fairly rapidly, the weight is reason-ably low and starting in cold weather is notaffected by the stiffness of the engine.

This EnliAlltenecl AbeBy LESLIE MADEN

DURING the past 5o.years there hastaken place one of the most remark-able and rapid changes in history.

Science, from being a strange new cult, stillgroping and struggling to clear away thecobwebs of ignorance -and superstition thatclogged and biased men's minds, has strivenforward surely and confidently, transformingon its way almost every sphere of life, andopeniffg up new and undreamt -of vistas.

Education, too, has made great progress,and now, more than ever before, ordinarymen and women have ample opportunity toform intelligent opinions of their own. Surelythen, this twentieth century of ours must bea very prosperous and happy period in whichto live ? There is so much to find Out ; somuch to perfect and improve ; so muchthat lies ahead of us. A golden age, indeed !

Yet, within the same short space of yearsthere has taken place a strange and ghastlyparadox, for while we have progressed, wehave also regressed. Side by side with all thescientific wonders of the age, there has marchedan extraordinary chaos of savagery and bkiod-shed unparalleled since the Dark Ages.Civilisation has cracked, and the orack hasbroadened into an ever -widening chasm thatthreatens to engulf us.

How did it happen ? How has this madnesscome about ? In large measure, surely, itmust be attributed to our financial system.When money was regarded merely as a con-venient medium of exchange, it did no harm,but, unfortunately, it soon became thepredominating factor in all business trans-actions, its original purpose, which was tofacilitate the exchange of goods, being re-versed by the practice of using goods tofacilitate the amassing of money.

This false financial development did im-measurable harm to the economic and socialsystem of this country, and to many others.The marvellous inventions of science beganto be exploited for purposes which were war-like and horrible, and the thoughts of manypeople became correspondingly warlike and

horrible. They shut their eyes to the obviousimperfections of the existing social ,system.Anyone possessed of sufficient moral courageto question harmful and frequently treacherousactivities was invariably shouted down bycries of " Red ! " " Bolshie ! " or " Don'tinterfere with the man at the helm ! " Thefact that there was more than one man at thehelm, and more than one helm, and thateveryone was steering full steam ahead fora head-on crash appeared to be generallyignored.

Well, now the crash has come. The past.lies behind us-a black record of greed andgraft, and utter irresponsibility of outlook bythe common people towards their own much -boosted " self-government." We shelved theresponsibility of that govemineht On toanybody who cared to take it, and ttie presentinclicitions of the disinteation of thecivilised world are the bitter ft:slidOf diI folly.The future stretches before us-grim, darkand uncertain. No one seems eager to tacklethe vast problem of post-war resonatuction.Instead, we are given smooth assurances thatit can quite safely be deferred until " thisHitler huainess is finished."

But wouldn't it be better to face it now ?Wouldn't it give us more zest for the struggleto know, once and for all, what we are fightingfor, what are our common aims ? At themoment- different people seem to be fightingfor different things, some for the perpetuationof the old regime, and some for an improvedsocial system which has, as yet, rio practicalfoundations. Wouldn't it be better to lay thosefoundations now, firmly and securely ? Afterthe war we shall all be so confused andexhausted that no one will have the energyor enthusiasm to apply to the working -out of Inew social order, and it will no doubt be 4ideasy matter to convince us that the old Systeril,with all its miserable weaknesses and in-justices, will be the most conyitsient. " Aftetall," the politicians will tell " 1 js estab-lished, it has been tried befor6"however, neglect to add " e

January, iY43 NEWNES PRACTICAL MECHANICS

Reclaim in Porous CastingsHow Defective Castings are Made Good with Special Sealing Solutions

IT is well known in engineering circles thatin spite of the utmost care in manufacture,metal- castings often show porosity, al-

though the defect is generally slight. Thisporosity, however, may be sufficient to causerejection of the castings with consequent lossof money, time and labour. In the case oflarge objects, this return to the melting potis much to be deplored, especially as an'efficient- and 'simple remedy can be found.A British product has been introduced in thiscountry by Bakelite Limited, of London andBirmingham. For overcoming -porosity, seal-'ing solutions are used, namely, BakeliteV.1845 and N.zto6. The former is a clearsolution of a special resin and is used in casesof fine porosity, whereas the latter is a solutioncontaining a finely divided mineral filler andis employed when the porosityis of a grossernature. These solutions may be used forboth ferrous and non-ferrous metals, andfactory trials have demonstrated conclusivelythat the results produced are. highly satis-factory.

Sealing SolutionThere are two main methods, one, for small

castings, by which the sealing solution isforced into the casting by external pressure,and the other, for large hollow castings, byWhich the solution inside the casting issubjected' to pressure, thereby forcing thesolution through the walls from the interior.The small castings can be treated by the wellknown vacuum -pressure process, in which thecastings are placed in a strong container fromwhich the air can be evacuated. When asuitable vacuum has been attained, the sealingsolution is allowed to run in from the storagevessel until the castings are covered, afterwhich pressure is exerted for a convenienttime. The solution is thus squeezed intothe body walls of the casting, filling the pores.After removal from the vacuum -pressurechamber, the castings are submitted to abaking operation to be described later.

For Large CastingsIn the case of larger hollow castings an

example may he taken of one having severaloutlets. All but one of these apertures areclosed, the opep one being used as a port forfilling the casting with the sealing solutionand as an opening through which pressuremay be exerted. The casting may be eitherin the trimmed or untrimmed condition, sincefinal machining can be carried our aftersealing, if desired. When the remainingexits of the casting are effectively pluggedand the hollow casting is filled with the sealingsolution, air' pressure is applied at the openport so that the solution is forced from theinterior into the pores of the metal. Anyavailable pressure from 5o up to 25o lb. persq. in. may be used. If any porosityexists, the solution is forced through so thatsweating occurs on the outside surface of thecasting ; although in the case of gross defectsthe solution emerges as a spray. While it isprobable that a casting showing such leakswould be returned to the foundry, it may bestated that even severe porosity can be curedby two impregnations of the solution N.21o6,followed by intermediate stoving.

. _

PolymerisationBy this impregnation process, which is

carried out at normal atmospheric tempera-ture some of the sealing solution remainswithin the walls of the casting,; the next stepis to " fix " it therein. The solution consistschiefly of a Bakelite synthetic resin which,

by the application of heat, is converted froma soluble and fusible substance into a solidwhich is no longer soluble or fusible, andwhich is highly resistant to nearly all formsof attack. This transformation is known aspolymerisation, and Bakelite in this curedcondition has no known solvent. The firststage of the baking process removes thesolvent, and further heating leaves the pores ofthe casting filled with a chemically inert solidwhich cannot be removed by any pressuresapplicable to the casting in service or on test.

In order to effect this polymerisation, thefollowing procedure is adopted, althoughmuch latitude is permissible :

r. After the pressure has been exerted forsome time as is considered necessary, thecasting is drained and lightly wiped with acloth moistened with a thinning solution(also supplied by Bakelite LimIted) in orderto remove the excess of material adhering tothe surfaces of the casting.

2. The casting is now placed in a suitableoven, well ventilated, at ordinary atmospherictemperature. Heat is applied so that duringthe first hour the casting is brought to atemperature of about 85 deg. C.

3. After the solvents are removed, thetemperature is raised to about r so deg. C. foran hour and finally raised to 135 deg. C. for a similar period.

When the stoving cycle is complete the

casting is. sometimes refilled with sealingsolution and again subjected to pressure.This second impregnation will test whetherall the pores are filled ; if any sweating canbe observed the casting is ready for a secondstoving; which, however, is seldom required.

Hydraulic TestsIt will be noted that the castings have not

been subjected to the usual hydraulic test ; noris this necessary, since the sealing solutionitself acts as a pressure test medium whichwill detect any porosity and at the same timewill charge the metal with the filling fluid, thuseffecting a great saving of time. In fact,water must not be used ; or if it were used as atest liquid, the casting must be dried thor-oughly before the solution is placed therein.Of course, after the process of impregnationand stoving has been completed, the usualhydraulic tests may be carried out.

This method of salvaging porous castingsshould be especially welcome under warconditions when time is so valuable and whenevery porous casting thus salvaged can be putinto service, instead of beng returned as scrapto the melting pot. The material is statedto be' inexpensive, and little is actually con-sumed by any casting, since any solution whichhas not entered the metal wall is returned tothe storage vessel for use upon subsequentoccasions.-Machinery.

WAR -TIME BATTERY THREE(Continued from page 527.)

plus in. turn up for fixing. We were ableto use a piece of thin aluminiwn, and this isto be recommended if available, but failingthis, zinc-plain or perforated-or a piece oftinplate could he used.

Little can be said about locating the com-ponents, as their relative positions are clearlyindicated on the plan drawing. A wordabout the screen and coils is, perhaps, advis-able, as it is essential for these to be fixedin the positions shown otherwise instabilitymight be produced, due to the fact that thecoils themselves are not enclosed in screeningcans.

After the valve holders, H.F. choke, two -gang condenser, terminal strips,' and com-ponent brackets have been fitted, the screencan be screwed in position, but only after thefour holes have been drilled in it to allowthe filament wires, the anode connection, andone lead to the fixed vanes of the front sectionof the two -gang condenser, to pass through.The fixing and wiring of the coils should beleft to last, otherwise there will always bepresent the danger of damaging them. Theirconnections are shown quite clearly on thewiring plan.

It is essential to see that all connections,escially those to earth, are electricallysound, and we strongly advise soldering. Apoor or intermittent connection can ruin theefficiency of any circuit, therefore, if terminalsare used see that their contacting surfacesare bright and clean, and that the head isfirmly screwed down.

Variable FactorsIt will have been -noted that the primary

windings of the aerial and R.F. coils are notthe same. This is due to the fact that theturns on the R.F. transformer were adjustedto give a degree of coupling satisfactory for acertain measure of selectivity and transferenceof energy.

The turns on the aerial coupling coil werelikewise governed by selectivity, bearing inmind the varying types of aerial with whichthe set is likely to be used, and the widelydiffering locations. If, therefore, in anyparticular district a greater degree of selec-tivity is required, a few turns can be re-moved from the coupling coil, but it mustbe remembered that signal strength will alsobe reduced.

Two separate .0005 mfds. tuning con-densers can be used in place of the two -gangcomponent, but if this is done then theymust be located so that the screen comesbetween them.

OperationAfter completing all wiring, have a final

visual examination and, if possible, applysimple continuity test to satisfy yourselfthat no short-circuit exists between the H.T.positive lines and the L.T. or earth, beforeconnecting batteries, etc.

For ILT. positive r use 12o volts H.T.,for H.T. positive 2, 6o to 7o volts, and withthe output valve specified .4! volts grid bias.After connecting aerial and earth, accumu-lator and speaker, set the reaction control(the right-hand variable condenser) to mini-mum setting and switch on by means of thepush-pull switch.

Rotate the two -gang condenser control untila transmission is heard ; open the aerialseries condenser to reduce volume, and thenadjust the trimmers on the ganged condenseruntil the best result is obtained. Now closeaerial condenser, and bringing up reactionuntil the circuit is just below point of oscilla-tion, search for a signal towards the upperend of the tuning scale, i.e., ganged condenserclosing. After making sure that no oscilla-tion is present, again adjust trimmers to see -ifresults can be improved. Repeat the pro-cedure on a transmission at the lower end ofthe tuning scale, the idea being to obtain themost satisfactory trimming adjustment forthe whole medium -waveband.

136 NEWNES. PRACTICAL MECHANICS JanUary, 1943

THE earliest races of mankind mustinevitably have been aware of the factthat some materials dissolve in water

whilst others obstinately refilse to behave inthis manner.

Common salt is an example of the firstcategory of materials ; sand is typical of thesecond group of substances.

Possibly, too, our remote ancestors werecognisant of the fact that soluble substancesdissolve more readily in hot water than theydo in cold, but, so far.as we can tell, they donot appear to have had any clear notionsas to what happens to a substance hen itenters the dissolved state.

Modern chemistry, when it was firstfounded in the z8th century, was far too busywith other matters to look into the questionof the dissolved state. That remained atopic which was only taken up and scienti-fically examined at a comparatively late stagein the development of chemical. science.Even at the present time, the .subject ofsolvents and the true nature of solution has byno means been thrashed out to its ultimateextent.

Gases in SolutionOrdinarily speaking, we are all apt to regard

a solution as a liquid containing a solid whichhas dissolved in it. There are other solu-tions, however. A gas can dissolve in aliquid to form a very strong solution. Anexample of this is the " ammonia " of thedruggists' shops and household stores. Thisis a solution of the gas, ammonia, NH,,, inwater. Perhaps, as some chemists maintain,some of the ammonia gas may have actuallycombined with the water to form a definitechemical compound, ammonium hydroxide,NI -14.0H, but that probable fact does notinvalidate the argument that this. " liquorammonia:" contains a large proportion ofammonia gas which has actually dissolved inthe water.

Hydrochloric acid, HCi, is another similarcase, for here we are confronted with a solu-tion of hydrochloric -acid gas in water.

It is also a fact that one solid can dissolvein another solid. Molten glass, for instance,can dissolve certain metallic oxides whichimpart to it characteristic colorations.Rocks, too, can contain metallic compoundsin the dissolved condition, and there areexamples, also, of solids containing dissolvedgases, although in the majority of., cases aliquid tends to expel its dissolved gases beforeit congeals or solidifies.

Wo 'see, however, that the peculiar natureof solution is not one which is confined solelyto solids and liquids. Given suitable con-ditions, any form of matter can enter intothat peculiar state of union with another formof matter to which we apply the term " solu-tion."

Salt and WaterIn modern chemical science, the substance

which exerts the dissolving action is calledthe solvent. The material which "is dis-solved by the solvent is known as the solute,and the substance or medium which resultsis termed the solution. Thus, in the case ofsalt .and water, the salt (sodium chloride) isthe solute, the water is the solvent .and theresulting liquid is the solution.

Let us now consider this common exampleof salt and water a little more closely. Every-one knows that if you stir a small quantity of

The Story of Chemical DiscoveryNo .18-The Study of Solutions, or Matter in its Dissolved State

common salt into a basin or a tumblerful ofwater the salt will disappear from sight. Ifit cannot be said to " vanish into thin air,"it can certainly, and with all truth, be main-tained to have " vanished into thin water."

What has become of the salt during thiscommon yet mysterious process ? Obviously,

Svante Arrhenius.

the salt has, in some way, mingled with thewater, because it imparts its own charac-teristic salty taste to the water. And further-more, if we evaporate the water by boiling,the salt remains behind after all the waterhas been driven off.

Still more, the salt is not in any waydestroyed by the strange disappearing trickwhich it performs during the act of solution,for if we dissolve an ounce of Salt in a pintof water and then carefully boil the water offwe shall get back exactly one ounce of thesame salt. Solution, therefore, is mostclearly and emphatically not a destructiveprocess.

Stippose, now, that to our basin or tumbler-.ful of water we keep adding salt in smallamounts at a time, stirring the liquid well

A typicalelectro - platingbath for smallobjects. Thetheory of -elec-trolytical disso-ciation explainsthe phenomenonof electro-plat-ing by assumingthat the electricpotentialapplied to thebath gives direc-tion to thelionsinto which thedissolved s u b -stance is split

up.

after each addition of salt to ensure that allthe salt has dissolved before a fresh quantityis added. We shall find, in this instance, thatwe can only go on making fresh additions ofsalt for a limited time, because, after acertain quantity of salt has been dissolved inthe water, the latter will resolutely refuse todissolve any more of the salt.

If, now, we take the solution of salt inwater which refuses to dissolve any furtheramounts of salt, and if we warm that solution,we shall find that it will again dissolve moresalt. But, if, afterwards, we allow thatsolution to cool, the extra amount of salt,which it has dissolved. at the higher tempera-ture will again appear in the liquid as thelatter cools, the salt, in this case, being" thrown out " of the solution.

" Saturated " SolutionsLiquids, therefore, can only dissolve a

limited amount of solid material at any onedegree of temperature. A solution whichcontains the maximum amount of dissolvedsubstance or " solute " is known as a " satur-ated solution." The precise strengths of allsaturated solutions depend upon the tem-perature of the solution, its chemical natureand, also, Upon the chemical nature of theft" solute " or dissolved substance.

Such facts are fairly well-known ones, andthey are facts which any seriously mindedexperithental amateur can easily confirm forhimself. They do not,. however, take usdirectly to an understanding of the realnature of the act of solution. In other words,they do not afford us a clear indication of whatthe fate of a teaspoonful of salt or sugarmay be when it is stirred into and dissolvedin a vessel of hot or cold water.

The clue to our present-day explanationof the problda of solution came in. a veryroundabout way. In or about the year 1877,a Gc-fman scientific wOrker, W. Pfeifer byname, a botanist, made a careful study of thecurious phenaiiiirn which occurs when apiece of paRhment or skin, is interposedbetween a solution of a salt and some plainwater.

If we tie or cement a piece of skin (suchas bladdef sjari) across the wide end of aglass fiuurs1 we 4011 have Whai is Called inchemical -science a " membrane " throughwhich water can freely pass; but one whichprevents the PaIsige through it of a dissolvedsubstance. Such a device is known as a" semi -permeable membrane."

January, 1943

Osmotic PressureNow, if we secure the funnel membrane

downwards in a jar of plain water, as indicatedin the illustration, pour into the funnel asolution of salt, and finally secure to theupper end of the funnel stem a bent tubecontaining a little mercury, we shall find thatafter the funnel has remained in this positionfor some hours the mercury in the opencolumn has been forced upwards, thusindicating the fact that a definite pressure hasbeen generated within the apparatus.This degree of pressure is now spokenof as " the osmotic pressure of the saltsolution " (Greek : osmos, " a push.").

Whence can this clearly -demonstrablepressure have arisen ? Investigation inall such circumstances reveals a verycurious action" to have taken place. . Theparchment or skin membrane passes waterfreely in either direction, but it, will notpass the dissolved salt. If the membranehad permitted the water and the dissolvedsalt to pass freely in either direction thenet result, after a time, would have beenthat some of the dissolved salt on one sideof the membrane would have passed throughthe membrane and would have diffused intothe plain water. Under these circumstances,this process would have continued until thebalance of salt and water had equaliseditself on both sides of the membrane.

In the case of a semi -permeable membranesuch as we have just described, however, arather extraordinary thing takes place. Since,owing to the presence of the -semi -permeablemembrane, the dissolved salt cannot get tothe plain water, the plain water actually goesto the dissolved salt. Because of the waterwhich passes through the semi -permeablemembrane to the dissolved salt, an extrapressure is generated on the solution side ofthe membrane, and it is this pressure whichis indicated by the pushing up of the mercuryin the bent glass tube.

Since this pressure (osmotic pressure) isclearly demonstrable without the least shadowof doubt, it is obvious that it must be causedby something. What this mysterious " some-thing " is was, for a long time, undecided,but the modem theory is that the pressure isactually the result of the mass -bombardmentof the particles of dissolved salt against themembrane.

Consideration of this and of similar experi-ments led a number of physical chemists tocome to the conclusion that the molecules orparticles of a dissolved substance exist in awidely -separated condition within the solvent.

Plain Water

Capillary Tube containingMercury alVBend

Mercury

kti Cork or Rubber Bung

Class Funnel

Funnel filled with SaltSolution

Parchment Membrane lightlyWired on to

Class -lerSimple apparatus for demonstrating the "existence of

pressure," or " solutionpressure."


In its solid state, the constituent particlesof common salt cohere together in conse-quence of their own mutual attractions. Butwhen the salt is " dissolved " in the waterwhat happens is that the salt particles arerelatively widely separated. Each salt particlebecomes, as were, a particle of its own, anindependent unit, and, as such, it celebratesits newly -acquired liberty by skelteringhither and thither throughout the liquid inmuch the same way as a particle of a gas

scurries here, there and everywhere withina confined space.

In the act of solution, the particles ofliquid have, as it were, interposed them-se.ves or infiltrated between the salt

Illustrating the nature of a saturated solution.A beaker containing water and crystals of achemical salt. The water has dissolved a maxi-mum amount of the crystals, and it will not dis-solve more. The resulting clear solution is there-' fore "saturated."

particles. Whereas, in the solid state, oneparticle of sa.t was adjacent to another saltparticle, in th'e dissolved condition hundredsof millions of liquid particles may existbetween one salt particle and the next one.

The liquid particles are more mobile thanthe salt particles. Consequently, when all

the particles of liquid aredriven offby, heat all thatthe salt particles can dois to fall together againand to assume their originalstate. They have beenviolently careering throughthe mass of liquid particles,but now that the latter haveforsaken them they mustnecessarily return onceagain to.their old state ofmutual captivity.

Electrolytic DissociationThe modern theory of

the dislolved state and ofthe nature of solution is,for the most part, due toa celebrated Swedishchemist named SvanteArrhenius. He was bornin 1859 and was, from theearly days of his student -

end of Funnel ship at-Upsala and Stock-holm, particularly interestedin theoretical and physicalchemistry. Like many

" osmotic others, he pondered longand earnestly over the inner

137

and the real nature of solution. It seemed tobe a problem so close at hand, so intimateand yet so difficult of elucidation.

In his own words, Svante Arrhenius tellsthe tale of his now famous " theory ofelectrolytic dissociation " :

" I got the idea on the night of the 17thof May, 1883, and .I could not sleep thatnight until I had worked through thewhole problem. I had deduced a rathergreat number of different properties ofsolutions which had not been explainedbefore, but I must say that this circumstancemade no very great impression upon myprofessor at Upsala. I came to my pro-fessor, Cleve, whom I admire very, much,and I said, ' I have a new theory of electricalconductivity as a cause of chemical reac-tions.' He said, This is very interesting.'Then fie said, Good-bye.' He explainedto me later-when I was presented withthe Nobel Prize for Chemistry-that heknew very well that there are so many

'different theories formed, and that they areall almost certain to be wrong, for, after ashort time, they disappear ; and, therefore,by using the same statistical manner offorming his ideas, he concluded that mytheory, also, would not exist for long ! "Arrhenius's theory of solution has, however,

lived down mak of its opposition. Briefly,Arrhenius pictured a particle of common salt(sodium chloride) splitting up into twoparticles immediately it enters into dissolvingunion with the water. In the dissolved state,the particle of salt (sodium chloride, NaC1)automatically divides up into a particle ofsodium and a prarticle of chlorine. Theseparticles are termed ions, an ion being anelectrically charged particle.

Thus, according to Arrhenius, whencommon salt dissolves in water, it undergoes aprocess of " electrolytical dissociation " orelectrical separation. It splits up into :onsof sodium which are positively charged andions of chlorine which are negatively charged.

The electric charges which appear on theions come from the actual molecules of thesalt (sodium chloride), the molecu'es beingelectrically neutral in the whole or unseparatedcondition but developing polarity in theircomponents when they are split up.

When we pass an electric current througha solution of salt in water, we give systematicdirection to the ions contained in the solution.The positive ions (of sodium) stream towardsthe negative electrode, whilst the negative ions(of chlorine) flow towards the positive elec-trode. Thus it is that if we electrolyse asolution of salt in water, we obtain theliberation of chlorine gas at the anode andmetallic sodium at the cathode. (In thislatter instance, the liberated sodium instantlyreacts with the water, forming sodiumhydroxide or caustic soda.)

Arrhenius has thus given us what is moreor less the present-day accepted theory ofsolution.

Prof. OstwaldSvante Arrhenius was quite an unknown

man at the time of his introduction of histheory of solutions. Like Cleve, his professorat Upsala, most of the famous chemists ofthe day gave him and his theory little encour-agement. There was one celebrated chemist,however,. who saw the germ of genius inArrhenius's notions concerning solution, andthis was Ostwald, one of the " fathers ofphysical chemistry," who was then professorin the Uniyersity of Leipzig.

Ostwald championed Arrhenius's ideas onthe difficult and abstruse, yet none the lesshighly important, subject of solutions and, toa large extent, it was due to the Leipzigprofessor that they gradually became accepted.

Arrhenius died in 1926 at the not veryadvanced age of 66.


THE ORLD OFMODELS By MOTILUS'

Gauge " 0" " Duchess of Montrose"locomotive -1938, and " Ajax " model

locomotive -1892.

Fifty Years of Model Locomotive ProgressTHERE is a line in a verse of one of the

lesser known poets-" We dwellunjustly in the past."

I suppose all those who have passed theage of 6o do dwell-but not always unjustly-in the past. Henry Ford has said that welearn nothing from history except that welearn nothing, but, however true this may beof political history, it is certainly not truewhen applied to science and engineering.

In the development of model making as ahobby or craft I would say there has been noimprovement for hundreds of years in realcraftsmanship. In fact, some of the work otthe Chinese of a thousand years ago is finerthan any work done by the western civilisationsto -day. It is in the commerciallymade modelthat progress has been so rapid during thepast 5o years, in the making of publicity andmuseum models, but more in the adaptationof new processes and inventions and methodsof production, which has enabled firms toplace within the public reach, at reasonableprices, fine models, equal to many of the hand-made ones.

"Ajax" and " Zulu "For the purpose of this article I would like

to devote myself to just one aspect of progressin models, and that is the model locomotive.When I was a boy, about so years ago, theonly model locomotives available for purchase

ones is illustrated here. They were not in theslightest way scientific in their design and,although they would probably work for ashort time, the boiler was never powerfulenough to generate sufficient steam to supplythe cylinders continuously.

Fig. L-A Birmhighatn-madc modellocomotive-date about 1895.

11=1 r=r1El. 2 . -An oscillating cylinder steam 70,0 -

motive of 1898 (continental made).

The early clockwork locomotives of thesame period were mostly French and Germanmake, were very flimsy and light in weight.

Fig. 3.-A continental steam model locomotivewith piston valve cylinders -1901.

in the shops were those early steam modelswith green boilers and brass wheels, whichborelittle resemblance even to the locomotivesof their day. The " Ajax " and " Zulu " werecheaper models, and one of the more elaborate

in the museums of several cities of England,About this period there were some very

good commercially made model fittings andparts on the market for the use of modelMakers. Firms in Birmingham, too, wereimproving to a small extent the design andconstruction of model locomotives, whichwere sold mostly by opticians in those daysFig. t shows an illustration of a Birminghammodel of the 1895 period.

Foreign ModelsAt the Paris Exhibition of 1900 the con-

tinental toy makers, especially the Germans,made a very fine display of clockwork andworking steam model locomotives, and Fig. 2shows an oscillating cylinder steam locomotivefor the continental gauge of 35 m.m. (knownas gauge o " (iin.) in this country). Thisand several similar locomotives, including anAmerican type passenger train which com-prised 4-4-0 locomotive and tender, two4 -wheel coaches, a bogie salbon coach and anAmerican pattern brake van, were made bythe firm of Carette & Co., of Nuremberg.M. Georges Carette was a Paris -bornFrenchman, and established a factory inNuremberg with a German partner, PaulJosepthal (both of whom, incidentally, arenow in retirement, the latter in Palestine andthe former near Paris). Another Nurembergfirm-Gebrfider Bing-were also showing a

Fig. 6.-Scale Model steam M.R. locomotive by Bassett-Lowke-31in. gauge --built mainly from castings.

and represented for the most part crudereplicas of continental types. There weresome excellent scale model locomotives ofthat period made by skilled engineers andamateurs, many of which are still to be seen

gauge steam locomotive " Black Prince "-Igo!.

fine collection of mechanical, electrical andsteam toys, including steam locomotives.About the year 1901 they introduced a specialpiston -valve cylinder reversing by means ofa steam block operated from the cab or the

4.,

;.-Mode[ steam locomotive, G.N.R., 8ft.locomotive, 2 Un. gauge (1902).

January, 19 43 NEWNES PRACTICAL MECHANICS 139

rail, which reversed the steam inlets from steamto exhaust, and Fig. 3 shows one of the firstof these models sold in this country. Messrs.Bassett-Lowke, of Northampton, who hadpreviously confined theinselves to hand -mademodels, fittings and parts, now turned theirattention to the production of inexpensivemodel locomotives, and the first one-madein 1900-was a 4-4-0 L. and Y. locomotive,driven by two inside oscillating cylindersplaced between the frames.

The " Black Prince "Later they made use of the continental

piston -valve cylinders, and the first model ofthis type was the 21in. gauge " Black Prince,"Fig. 4, which caused quite a sensation in themodel -making world.

A model engineering journal in 1901referred to this model in the following terms :

. . . a really creditable representation ofthe `Black Prince' L. & N.W.R. locomotiveand tender, with piston -valve cylinders andreversing motion, which is deserving of greatpraise as a genuine step in the direction ofmore realistic models than have often beensupplied by professional model makers. Aftera practical trial of a sample engine, we.wereable to commend Pits good running ability.One of the happy purchasers of a similarengine writes : ' With only four burnersgoing, and running light with tender only, itran without a stop for 4o minutes, and coveredover 3,000 yards . . . " From that pointprogress increased. The gauges for commercialmodels at that time most in use were in. and

except on the continent, where smallergauges were in vogue.

The construction of the "Black Prince,"was practically all sheet metal, the only cast-ings being for the wheels. These were not toscale but light in weight and construction.

The model introduced from the continentby Messrs. Carette was a G.N. 8ft. Single,No. 776 (Fig. 5), and here castings play alarger part in the construction. The side -frames, the splashers and front buffer beamswere fine iron castings, but the model was -nota' great success from the working point ofview because it was too heavy for the lowworking pressure of about 4016.. All thesesteam models had a plain cylindrical boiler

In the year 5903Mr. Bassett-Lowkehelped in an effort tosatisfy the taste ofthose who built theirown locomotives andrequired a full set ofworking drawings andcastings for a well-known type of Britishmodel. The Mid-land Compound ofthat time was decidedupon. Patterns weremade and it was certainly a mile-stone in the production of complete setsof castings and parts for the amateur.The gauge was 31in. and the scalewas gin. to the foot, and the model whencompleted and used with scale model per-manent way, made one of the finest scalemodel outfits that it was possible for theamateur to make, and placed the buildingof a model locomotive within the reach ofmany new enthusiasts. (Fig. 6.)

Progress was very rapid between this periodand the outbreak of war in 1914 and manyfine models were introduced, both in clock-work and steam, including a G.N.R. Atlantic

Fig. 9.-An inexpensive 4-4-0 filockworklocomotive-gauge " 0 "-introduced in 1926..

(Fig. 7) in clockwork and electric, a G.W.R.County class in steam and the -Midland Com-pound in gauge 1, also the L.N.W.R. "SirGilbert Claughton " and rolling stock in tin-plate in the various companies' style andcolours. The outbreak of the last Great Warbrought the production of all articles of thisdescription to a standstill, as it has done in thepresent hostilities.

" All -British " ModelsIn 1918, soon after the termination of the

last war, Messrs. Bassett-Lowke put down

Fig. 8.-Peckett tank locomotive in gauge " o " and '-clockwork.

and were fired by wick methylated spirit plant to enable them to produce " all British "lamps. made model locomotives, in clockwork, steam

and electric, and made themselves virtuallyScale Model Permanent Way independent of continental parts. (Fig. 8.)

The chief track in use at this time was the There was a great revival in the interest inwell-known tinplate track, but in the year model railways and this was well catered for1962 Mr. George Winteringham introduced by the introduction of many famous andscale model permanent way to a scale of -in. .inexpensive model locomotives, among whichto the foot, which was afterwards also pro- may be mentioned the 4-4-o clockwork loco-duced in Hn. scale and is also used to this day motive (Fig. 9). Another interesting modelfor gauge " o " and upwards. was the 2-6-o Mogul produced in L.M.S.,

L-lima_ 111

Fig. 11.-L.M.S. " Princess Elizabeth," gauge " o "-1936.

Fig. 7.-G.N.R. Atlantic type loconwiive in clockwork (gauge 1).

L.N.E.R. and G.W.R. types (Fig. to), whichwas made up as a set of parts at a later period,having for its predecessor the set of parts forbuilding the gauge I Midland Compound.Another type which contributed to the popu-larity of scale models in gauge " o " was theclockwork driven " Princess Elizabeth " whichwas also made in A.G. and D.C. electric.(Fig. ii.)Introduction of " oo " Gauge

-In the year 1926 there was introduced fromthe continent " oo " gauge, which was anothermilestone 'in model railWay history, its ' sizeand gauge being 4 mm. to the foot and gin.gauge (half " o " gauge). This Was laterdeveloped into the famous Twin Trix rail-way, which before the war had an enormousfollowing.

At the introduction of streamlining of ourmain line railways replicas in gauge " o "were introduced both in L.M.S. andlivery. In fact the L.M.S." Coronation Scotmodel (Fig. 52) was on sale in London theday the locomotive itself made its first publicjourney from Euston to the North. Following .shortly on this was the appearance of themodel L.M.S. " Duchess of Montrose," lastpre-war all -British model, recognised by allconnoisseurs of model ,locomotive productionas the finest commercial article then produced-at a reasonable price! (See illustration inheading.)A High-class Scale .Model

This brief survey of model locomotiveprogress would not be complete without areference to the fine 2 Ain. gauge model of the" Flying Scotsman," constructional details ofwhich were given in PRACTICAL MECHANICSduring the early part of 1940. The first com-pleted model was constructed at the North-ampton works of Messrs. Bassett-Lowke, whoalso supplied the castings and all materialsfor making the model. The finished locomo-

Pr Mogul locomotive in gauge " o "-produced in 1925.

tive was an example of the finest modelengineering craftmanship.

At this high spot we conclude the story,hoping that we may come back ere long tothose happy days of peace, when the makersof commercial models may go full speed aheadwith the experience they have gained, sadlyinterrupted by two major wars, to give us evenbetter productions and refinements that haveyet been thought of in the world of modelrailway operation.

- - - mk - -- --Fig. I2.-Model streandined locomotive " Coronation Scot "-

clockwork and electric -1937.


OurDevice for De-icingTACK FROST is a fifth columnist, so farJ as the propeller blades of aircraft areconcerned. The de-icing of these blades isthe subject of a recently accepted applicationfor a patent in this country.

The invention consists of a propeller bladewhich has conduits for de-icing fluid. Theseconduits are built into the structure of theblade.

A New Dress FormAN inventor has been devoting his attention

to the production of an effective dressform in order to assist the dressmaker to fither customers. It appears that many attemptshave been made to produce from a livingmodel a dummy which is an exact replica ofthe feminine human form. For example, ithas been proposed to mould the dress formby using Vaster of Paris, wet papier mach&glued paper tape and other materials. Butit seems that none of these substances isentirely satisfactory. When exposed to damp,they become distorted and, being fragile,they are easily damaged. Also, when madefrom the living model, they cause discomfortto the person upon whom they are shaped.

' Another idea for forming lay figures fromliving models has been moulds constructed insections. These may be made of modellingcompound such as is used by dentists fortaking impressions of their patients' mouths,or of any other soft substance which, whenheated, is plastic and, upon cooling, becomesrigid.

In this instance, each section is encasedin a close -fitting cover of pliable materialsuch as Jersey cloth. And the sections, afterbeing heated to render them soft and plastic,are then connected by spring clips. Lastly,the flexible mould is placed on the model,the sections are fitted and the mould, .whencompleted, remains on the model until itbecomes cold and hard.

Good FormTHE inventor of this improved device

maintains that it obviates the drawbacksassociated with previous methods and heaffirms that he has produced a light, tough,resilient form shaped accurately and withoutinconvenience to the living model.

His process consists in providing the modelwith a protective vest._ Upon this vest heassembles and moulds to the contour ofthe model a number of stretchable setdonsof thermo-plastic sheet material. This hasa fabric base impregnated with a compositionof vegetable wax, rubber, beeswax and resin,which has been heated and rendered plasticand adhesive. While plastic, the sheetmaterial is conformed to the living model,and the shell, thus shaped, is allowed tocool to room temperature and thereby stiffeninto a form which may be removed in sectionswithout distortion.

By means of this invention a woman mighthave made for her a kind of last in the shapeof her complete form. And, as a consequence,it would ensure a perfect fit with a minimumof visits 'to her dressmaker.

Glider ReleaseTO -DAY in the theatre of *war the glider

plays an important part, and a recentinvention relates to mechanism for the towingand release of these engineless aircraft.

The device comprises mechanism not onlyfor towing and releasing gliders, but also forsupporting and releasing bombs.

Busy InventorsBy "Dynamo

According to this invention, an attachmentplate has a recess into which a plug fits. Theplug has an eye for connection to the loador towing cable. It also possesses a hook -shaped head or projection engaging with apivoted hook mounted in a socket at the back

The information on this page is speciallysupplied to " Practical Mechanics " byMessrs. Hughes & Young, Patent Agents, of7, Stone Buildings, Lincoln's Inn, London,W.C.2, who will be pleased to send free toreaders mentioning this paper a copy of theirhandbook, " How to Patent an Invention."

of the attachment plate. The pivoted hook sassociated with a locking and release mechan-ism, by means of which the hook can beheld securely locked in one position, andturned to release the plug when required.

Air Mine

AS a defence against air -raids, it hasalready been proposed to suspend a

high explosive charge by a wire from a free

ject is to constitute a curtain of defence inthe aerial path of the enemy.

Fitted to the container are external fins.And in the event of the balloon being de-stroyed, the air mine automatically explodeswith safety, before it reaches the ground.This is caused by one of two methods or acombination of both. The increased airresistance, when the air mine 'drops, is usedto force a propeller and screw in contact witha percussion cap. Or the air velocity exerts apressure on a diaphragm at the base of themine and detonates the explosive.

The inventor states that the, approach ofaircraft will not disturb these mines pre-maturely ; but contact with one of themor a wire will cause complete destruction.Siamese -twin ShellsTT is claimed for a new form of projectile

that, while it can be fired from a gun ofordinary construction, it possesses a widearea of striking power. It comprises twoportions adapted to be separated, while in theair but to remain connected by a chain orCable. The two portions each contain a

bursting charge. Oneof them has a chambercontaining the chain orcable. These two por-tions are separated bythe action of heatand a delay -action fuse,and their charges areexploded by impactwith their target orby a separate delay -action fuse.Sealing Broken Gas

Mains

A model of k tank shown to the National Inventors Councilin Washington, which, according to the inventor, is more powerfulfor quick thrusts into all kinds of terrain than anything now beingturned out. It is also equipped with a bridge inside, which canbe let out in front when the tank reaches a narrow stream,

allowing it to go over instead of through the water.

balloon. The charge is designed to beexploded by enemy aircraft coming in contactwith it. In one such proposal the devicehas been furnished with an external slow -burning time fuse, whereby the mine is,exploded after some time has elapsed, if ithas not been contacted by a hostile 'plane.

An application relating to an aerial barrieragainst enemy aircraft has just been acceptedby the British Patent Office. The inventionprovides means to control the period of theaction of what is termed an air mine.

The contrivance includes a light con-tainer having within it a high explosive chargewhich is attached by a long wire to a hydrogen -filled coloured fabric balloon. This balloon isfitted with an adjustable automatic internalpressure -operated gas valve to release acertain amount of gas, when the devicereaches the various heights required.

The gas valves of a series of balloons canthus be so adjusted that the air mines willascend to different relative heights. The ob-

TN an air raid thefracture of gas mains

is an ever-present peril.To protect against thisdanger, an inventor hasdevised a means forstopping, or " baggingoff," gas mains brokenin air raids.

Broadly speaking, thedevice consists of anexpansible bag or bal-loon which can be in -inserted in a fracturedmain. This is self -inflated by the evolutionof a gas generated bythe interaction of suit-

able chemicals brought into contact by theinsertion of the bag.

Easy ShavingAMONG recent applications for a patent

in this country is one relating to dryshavers having free or floating blades whichrotate in contact with a shear plate. Thenew invention includes a support for a bladeof this character. In all its operatidths the edgeof the blade is in intimate wiping contact withthe shear plate. Not only does the bladeact as an efficient cutter, but, in addition, theedge is continually sharpened by a sort oflapping action which prevents shaving fromdulling the blade.

The device comprises a blade looselymounted in a rotatable support arranged sothat when the` supportbegins to rotate theblade tilts backwards, while the cutting edgetakes up an effective position with respect toa shear plate, behind which the support andblade rotate.


QUER1ESc.4ENQUIRIES

A stamped addressed envelope, three pennystamps, and the query coupon from the currentissue, which appears on back cover must be enclosedwith every letter containing a query. Everyquery and drawing which is sent must bear thename and address of the reader. Send yourqueries to the Editor. PRACTICAL MECHANICS,Geo. Newnes, Ltd., ToWer House, Southampton

Street, Strand, London, W.C.2.

Condensation' Troublej HAVE a sheet steel garage which, in" cold weather, has much condensationof moisture on its ceiling. I shall begrateful if you could recommend, aremedy to prevent this.-L. Cropper(Liverpool).THE condensation trouble which you

describe is a very common one.i It isalso a very difficult condition to remedy.The condensation is caused by the atmosphericmoisture condensing upon the cold surfaceof the sheet steel. Hence, anything whichyou can do to stop the conduCtion of heatthrough the metal will, wholly or partially,remedy the Condensation. For example, thesteel sheets might possibly be prote.-...ted-ontheir Outsides 'with tiles or asbestos sheet inorder to prevent or to inhibit the e cape ofheat from the interior of the garage. Thiswould go far to lessen the condensationtrouble.Some individuals have tried painting thetroublesome surfaces with paints containingfine asbestos, the idea here being to produce anon -conducting film on the condensation -laden surfaces. In some instances, this notionhas worked fairly satisfactorily ; but in othersit has failed.

We feel, therefore, that the most funda-mental advice which we can offer you is to.,the effect that you should make all, possibleendeavour to heat -insulate the surfaces onwhich condensation appears. If you caneffect this, the trouble will disappear, sincecondensation cannot make its appearance ona surface which is as warm as the air making

c. contact with it.

Wire for Spark CoilT HAVE on hand a quantity of No. 3oG

enamelled wire, about Ob. in weight.Would that amount of wire be suitable

° for making the secondary for aspark coil ? If so, what size of core andamount of wire, and gauge, will berequired for the primary ?-RobertDunting (Rochdale).THE quantity of wire you mention for the" secondary of a tin. spark coil js sufficient

in weight, but would hardly give a spark tin.long as its diameter is rather larger thanusual, and would, consequently, give in-sufficient number of turns. You may, however,get a sin. spark, and the relatively heavy gaugewill ensure a heavy current discharge, resultingin a " fat " spark. The size of iron corerecommended is lin. diameter by 7iin.overall length, composed of soft iron wireNo. 22 gauge. For connection to a 4 -voltaccumulator the primary should be woundwith two layers of No. 14 s.w.g. d.s.c. copperwire, and the condenser may consist of 6osheets of tinfoil 6in. by 4in., interleaved withwaxed paper.

Removing Ink SplashesT SHOULD be grateful if you could tell

me how to remove ink splashes froma much valued book without defacing thepage.-H. A. Burrough (Bristol).

WE might have been of more detailedassistance to you if you had told us

what type of paper the ink splashes have beenmade on ; whether they are large or smallsplashes, and whether they are made inordinary ink or with any special type of ink.However, assuming that the splashes are ofordinary writing ink on reasonably goodpaper you can eliminate them by saturating apiece of pure white blotting paper with asolution of sodium hypochlorite (ordinary" Milton " will do). The blotting paper isthen laid down on the ink splash and pressedfirmly into contact with it for a moment ortwo. After this, take a clean piece of cotton -wool, dip it into a weak solution (say, 5 percent. solution) of hydrochloric acid (spirits ofsalt), and wipe it lightly over the ink splash.The latter will disappear almost instantly.The area of paper where the splash has beenshould now be carefully wiped over withanother piece of cotton -wool which has beendipped into hot water, and then -wiped over apiece of soap. ThiS final treatment removes

OA.

Diagram of two -pole field magnet of the iron-clad type for a synchronous motor.

the trace of acid from the paper, which acid,if it were not removed, would slowlydisintegrate the paper.

The above two solutions (i.e., sodiumhypochlorite or " Milton " and 5 per cent.hydrochloric acid) should be procurable fromyour local druggist. Or, if you prefer thishighly efficient two -solution ink -eradicatorcan usually be obtained from manufacturingstationers and dealers in office supplies.

We must again stress the tact_ that, afteryou have removed the ink stain, you musttreat the paper gently with soap and water inorder to remove all traces of acid.

When performing the operation of ink -stainremoval always take the precaution of havingone or two sheets of waxed paper under thesheet undergoing treatment in order to keepthe solutions from making contact with theunderlying papers. Use all solutions assparingly as possible and do not attempt

to dry the paper by ironing or by heat. Allowit to dry spontaneously. Then, when it isdry, you may iron it in order to flatten it andto smooth it off.

Commutator -type RectifierT AM thinking of constructing a small

synchronous motor to drive a commu-tator type rectifier, and I should be obligedif you could help me by clearing up a fewpoints.

I want this motor to run off a 52-20 V.5o cycles supply at a speed of 3,000 r.p.m.,and to develop enough power to drivethis rectifier, which has four brushes.It will have to be a two -pole job, andI want to make it self-starting if possible.

(t) What size and shape should I makethe laminated field magnet ?

(2) Will one coil be sufficient for thewindings, and how many turns, and whats.w.g. wire will be necessary.?

(3) How wide and what length shouldthe rotor be ?

(4) Of what material should the rotorbe constructed ?

(5) Will shading" opposite halves ofeach pole face with a copper band makethe rotor self-:staiting ?=-J. Burnell(Barnstaple).TF the 4 -brush rectifying commutator runs

freely without a 'great deal of frictionalresistance from the brush pressure an armatureof the H -type, zip. diameter by x- in: long,should, suffice for the synchronous motor.'Both field Magnet and 'armature must belaminated, the former being of the "2 --poleironclad pattern to the dimensions- of .accom-panying sketch, the two field coils beingwound each with 45 turns of No. 18 s.w.g.d.c.c. copper, for operation on a 20 volts A.C.circuit. As regards self-starting this presentstoo many difficulties to be practicable onsuch a small scale, and is hardly necessary, asa spin of the shaft with the fingers in eitherdirection should cause the rotor to run up tosynchronous speed if the brush pressure isrelieved momentarily. The starting torquederived from "shaded " pole -tips by meansof copper loops is negligible for such smalldimensions.

Chemical Cigarette LighterCAN you please give me any informa-

tion about the chemical (non-electric) cigarette lighters, as used byquit,: a large number of Americansoldiers ? I understand that to light acigarette one has merely to insert tip ofcigarette into a special opening provided,and to draw in ; the chemical compositioninside lights the cigarette, due to the airpassing over it.-F. Peover (Maccles-field).

QUITE a number of " chemical " cigarettelighters have been attempted from

time to time, but none of them have everbeen very successful for the reasons that, so

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far, their action has been, to say the least,highly erratic. They often manage to con-taminate the cigarette with the taste orflavour of traces of chemical, and none ofthem is without danger.

You do not state the actual make of lighterwhich you refer to, but, from your descrip-tion, we should judge that the gadget com-prises a metal case enclosing asbestos packingwhich has been impregnated with red phos-phorus in a finely -divided state. When theend of the cigarette is inserted into thecontainer, it picks up a trace of the phosphorus,which latter, due to the friction created bythe withdrawal of the cigarette, ignitesmomentarily and so lights the cigarette, thisaction being aided by inhaling a current ofair through the cigarette when it is in positionin the lighter.

None of these lighters is manufactured ormarketed in this country, so that we have notavailable the precise details of the lighterconstruction which you require.

Noisy Gas FireHOW can I make a five -element portable

gas fire burn without noise ? Gasfires supplied by the companies burnsilently. Why ?-W. J. Welchman(Harrow).THE cause of noise with your gas fire is" probably due to one or more of thefollowing faults :

(i) Single -hole gas discharge orifice in theinjector. For silence this orifice should haveseveral (to -12) small holes in the form of adouble cross.

(2) The gas discharge orifice in the injectorhas a short channel compared with its dia-meter. A thin -walled orifice is generallynoisy.

(3) The gas discharge orifice is not con-centric with the mixing tube.

(4) The mixing tube has been left rough-cast; it should be reasonably smooth inside.

(5) The aeration is too keen. The bluecones at the burner ports should be fin. tolin. long. Adjust the air shutter to obtainthis result.

(6) The burner ports should preferably bemade of fireclay, and be divided into severalsmall holes.

(7) Excessive gas rate. When cones arehalf to three-quarters of an inch long the flameshould reach three-quarters of the length ofthe radiants.

First check points 5 and 7. When correct,this condition will give the quietest possibleoperation without making alterations to thefire.

Concrete FillerCAN' you give me any information

regarding the new concrete whichcan be sawn and nailed like wood ? Iknow that sawdust and cement is used,but do not know in what ratio. Is thereany chemical used to treat the sawdust ?If so, what is it, and where can it beobtained ?-Geo. Thomson (Leven).'THE special form of concrete to which you

refer is probably that made with a" filler " consisting of a mixture of sawdustand asbestos. You can make -such a con-crete in the following manner :-

Asbestos powder .. .. 58 partsDried clay .. .. 42 partsSawdust .. too partsIntimately mix the above ingredients in the

dry state. Then add four parts of the abovemixture to one part of dry Portland cement.Mix well and slake with cold water to form asloppy paste.

If you have any difficulty in obtainingsupplies, or if you are in need of furthertechnical information, we would suggest thatyou communicate your requirements toThe Associated Portland Cement Manu-

facturers, Ltd., Portland House, TothillStreet, Westminster, London, S.W.I.

Re -plating Accumulator PlatesIHAVE re -plated a number of lead

acid batteries, and find that thecompound is gradually coming off theplates although it has only been on for ashort time. I use the 40-60 formula,but I may add that the litharge and redlead is the ordinary commercial type,and not the special battery quality.Could I improve my compounding whenmaking the next batch of plates-if so,could you give me directions ?-PatrickO'Neill (Clare).THE cause of the paste failing to hold in

the lead grids is usually attributable toits being applied in too moist a condition. Avery stiff paste is essential, and if it can beapplied under pressure so much the better.Use brimstone acid only, for mixing the paste,not commercial oil of vitriol. A lengthyexperience in such work is essential to obtain

entirely successful results. Many usefulhints will be found in the handbook " ElectricAccumulators," by A. H. Avery (Cassell& Co.).

Winding Heating ElementsT SHOULD be very grateful for any

information you can give me regard;ing a machine for the winding of spiralsfor electric hot -plates, fires, etc.

The sizes of wire I intend to use are.0148, .0201 and .0179.

4 have constructed a machine, but amnot satisfied with the method adoptedfor feeding the wire on the mandrel, andI feel sure there must be some way toprevent it running back.-C. Shaw(Penarth).A METHOD of winding small spirals on

the lathe in gauges between Nos. 26and 36 s.w.g., which answers very well inworkshop practice, is shown in the accom-panying rough sketch. A hardwood or fibreT -piece A is provided with a metal bush atC of the same size as the silver -steel mandrel Don which the spiral is to be formed. Thecross piece B carries two eyes from which acord runs over two pulleys convenientlyfixed at centre height to some stationaryarticle, the cord carrying a weight H at thelower end which gives a steady tension end-wise on the spiral as it is wound.' Tension onthe wire is provided by a double washer andcompression spring L. The tail end of theT -piece slides easily between the two sidesof the lathe bed to prevent it from rotating.Close -wound spirals up to nearly i8in.overall length can be wound by this device,with ease and certainty, and afterwardspulled out, either hot or cold, according togauge of wire and spacing required.

Moulding PlasticsT WISH to carry out some experiments

on the moulding of plastics. Iintend to use steam or gas heated mouldsof dental plaster of Paris, and wouldtherefore require low-pressure and tem-perature thermosetting, or thermo-

plastic moulding powders. Is it possibleto obtain such moulding powders, and ifso, where can I obtain them ?

o you think I could obtain sufficientdetail, such as printing, and thin lines, byusing cellulose acetate in either sheetor powder form ?-J. Lloyd (Keighley).PLASTER moulds are not at all satisfactory

for compression moulding. Suchmoulds crack under heat and may only beused for sample or pattern making. If theidea is to cast these moulds, then lead maybe used, but still such material is not satis-factory for production purposes. Such mouldsare used only for casting either resins or coldmoulding compounds. If experiments arerequired to be carried out a plaster cast canbe used for casting back both male andfemale in aluminium alloy.

-Re-purifying French ChalkI HAVE about 6lbs. of French chalk

(talc) that is not 'quite clean. Willyou please inform me as to how I could

re -purify it ? - F. G.Harding (Churchdown).WE cannot give you

specific advice re-garding the cleaning ofyour French chalk, unlesswe know exactly what typeof contamination it isaffected with. Is the chalkgreasy, or contaminatedwith colour pigment, soot,carbon, dust or grit.

You say that the chalk is" not quite clean," and,

therefore, we assume that it has undergonesome sort of dust or dirt contamination. In thiscase, your best plan, first of all, will be to rubthe chalk through some coarse -mesh fabric, and' afterwards through some finer fabric. In allprobability this may completely remove theimpurities. If this treatment fails, try bringingthe chalk to red -heat in a suitable earthenware(not a metal) vessel. This may serve to -burnout the impurities (which may be com-bustible), after which treatment the chalkshould be sieved as before.

It may also be possible to " wash out "the impurities by stirring the chalk into a largevolume of water and then allowing it to settle.With this treatment, the impurities will mostprobably rise to the surface of the water andwill thus be readily swilled away. If youadopt this treatment you will, no doubt,have to repeat it several times before all theimpurities have been washed away.

v.

Simple device forwinding the wirefor heater

elements.

Slow-speed GeneratorT HAVE a Rotax dynamo (x2 v. xo amp.)

and I wish to use it as a wind -charger.Can I have it re -wound as a slow speeddynamo (about 45o to 800 r.p.m.) to givexo amp. output ?-C. Kemp (Enfield).you cannot rewind any dynamo to give

its normal full output at only a fractionof its normal speed, even by specially re-winding. If you reduce the speed of thepresent car dynamo from, say, 1,200 r.p.m. toboo r.p.m., as suggested, the result will be 4

either half normal volts, namely 6 volts Toamperes, or half the current output, namely52 volts 5 amperes. You ,can slightly lowerthe usual speed by specially rewinding thefields with a larger gauge of wire, but it wouldreduce the efficiency and call for considerablymore driving power, which is a disadvantagein the case of wind -driven generators. By re-winding the armature with more conductorsand leaving the fields unchanged you canobtain the 52 -volt output at a lower speed, butat the expense of output in current, since thearmature wire will necessarily be of smallersize than originally, in order to get the extraturns per slot.


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MORSE KEYSPractise on a regulation size Tapping Key. Ourheavy brass model is mounted on a wooden base,has an adjustable gap and nickel contacts. Key la ,wired to work buzzer or flash lamp by using a 41 -voltbattery or the transformer described above,BRASS KEY, 0/9, Chromium plated, 7/6. W.0 .Mode/ with heavy brass bar and the addition of afront bracket, 9/6. chromium plated, 10/6. Theabove keys are supplied to the Services for Morseinstruction. Slightly smaller Key, 5/, Junior Key,mounted on a bakellte base together with a buzzer.5/... Should you feitdre a complete outfit, our D.X.2Set consists of a heavy key mounted on a largepolished board, 10in. together with a buzzer,flash lamp, bulb and holder with two switches tobring either into circuit. Terminals are also providedfor distant vending and recehing, 19/, post Sd.

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WHY WORRY?.

WORRY tti,ei art immenseamount of vital force. People

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What do you suppose wouldhappen if a person who was puttinghinfself into mental, moral, andphysical bankruptcy by worrying,were to convert all this worryenergy into constructive 'action ? Inno time at all he, would have accom-plished so Much that he would havenothing tO" worry about. s

Nothing is more discouraging toa worrying person thah to havesomeone say, Oh, don't worry, itwill all come out right " ?

This is not reassuring at all. Theworrying one can't see how it isgoing to come out all right. But ifthe men and women who worrycould. be shown how to overcomethe troubles and difficulties that causeworry, . they soon would ceasewasting their very life -blood inworrying. Instead, they would begindevoting their energies to a 'con-structive effort that would gain themfreedom from worry for the rest oftheir lives.

You say that sounds plausible, butcan it be done ?

Half feesfoservilg embers ofHis Forces

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It can be done, and is being done,by Pelmanism every day in the year.This is all the more remarkable be-cause to -day the whole world is its anupset condition and people areworrying to an unusual extent. Yet,every mail brings letters to thePelman Institute from gratefulPelmanists who have ceased toworry.

People to -day are all too prone tocomplain that they just have toworry. But once they becomePelmanists they cease this negativeform of thought.

Remember-Everything yon do isprededed by your attitude of mind

The Pam= Course is fully des-cribed in a book entitled "TheScience of Success." The Courseis simple and interesting, and takesUp very little time ; you can enrolon the most convenient terms. Theliook will be sent you, gratis andpoit free, on application to :-

Pelman Institute,(Established over 40 years)

130, Albion House, New Oxford Street,London, W.C.1.

Readers who can call at the Institute will beweleomed. The Director of Instruction will bepleased to have a talk will' them, and no feewi.11 be charged for his advice.

PELM A N (OVERSEAS) INSTITUTES:NEW YORK, 271 North Avenue, NewRochelle. MELBOURNE, 395 FlindersLane. JOHANNESBURG, P.O. Box 4928.DURBAN,- Natal Bank Chambers (P.O.Box 1480). . DELHI, 10 Alipore Road.CALCUTTA, 102 Clive Street.

January, 1943 THE CYCLIST 25

VOL. XI

THE

5 I( .07Editot F. J. CAMM

cisJANUARY, 1943 No. 251

All letters should be addressed tothe Editor, "THE CYCLIST,"George Newnes, Ltd., Tower House,Southampton Street, Strand, London,

W.C.2.Phone : Temple Bar 4363

Telegrams : Newnes, Rand, London

Comments of the Month By F. J. C.

The Roadfarers' Debate on Road SurfacesNEARLY so members of the Roadfarers'

Club were present at the ClarendonHotel, on Saturday, November 2Ist, for

debate on road surfaces, which was precededby a luncheon. Lord Kenilworth was in thechair, and other important members includedMr. C. G. Grey, Major .Frank Bale, O.B.E.,A. Logette, A. H. Bentley, A. H. Burgess,W. G. James' Capt. F. C. Day, J. DudleyDaymond (chairman), C. A. Smith, W. J.Mills, Maurice Newnham, Dudley Noble,H. Boon, T. D. Osborn, R. A. West (secre-tary), V. S. Bowman, J. L. Callway, E.Coles -Webb, E. P. Richford, J. E. Rawlinson,and J. A. Masters. Sir Henry Maybury, whowas to have opened the debate, was ill andtherefore unable to attend.

Lord Brabazon, the president of the Road-farers' Club, had prepared a paper whichLord Kenilworth read in opening the debate.In the course of this paper he said : " I supposethere are more different road surfaces herethan anywhere else in the world. No oneseems decided as to the best. When I was atthe Ministry of Transport, I discovered thatin the north of London they were pulling upwood blocks and putting down granite sets,and in the south of London they were pullingup granite sets and putting down wood blocks.But why wood blocks ? Originally to preventthe noise of horses' hoofs, but if that is thebasis, then I wonder we don't put straw downeverywhere as we used to do for invalids.

Starting from London as you come onto the Kingston by-pass there are patches'of bitumen mixtures, each bit about 30o yds.long, which merit the attention of road users.As far as I remember, the fourth stretch isthe best, but they all show that bitumenwith its proper mixtures need not be slippery.Straight asphalt is a death trap, however, andis self lubricating. Some roads remain drylooking even in rain, others are always wetand seem to sweat under certain conditions.The construction of such should be avoided.

".The change when motoring from onesurface to another without notice is sometimesvery dangerous, as what is a perfectly safespeed on one surface may be unsafe on an-other.

" One word as to the ' hard ' or plainconcrete road. Is the 'alternate Bay formof construction essential, as it gives a poorride and often 'gets' in tune with the naturalup and down spring period of a car, when themost extraordinary results occur. Surely,as even on railway lines they are startingto do without breaks for expansion, longerstretches of concrete roads could be indulgedin.

" As to camber. Could instruction begiven as to which is the right way to ' bank'a road, or super -elevate it, as they call it, asI know of some examples of severe bankingwhich, under icy conditioni, are exceedinglyunpleasant.

Finally, why elevate kerbs ? Is this forornament, to keep the water on the road, orjust to keep the accident rate up ? "

Lord Kenilworth expressed the view withwhich many will agree, that the roads of this

country are, generally speaking, good, and hedisagreed with one of the speakers who thoughtthat borough surveyors were responsible forsome of the bad road surfaces. Lord Kenil-worth displayed great knowledge of roadmatters and road policy, and very ably con-ducted the meeting.

Another famous road authority expressedpleasure that the Roadfarers' Club has in thevery early stages of its existence realised thatroad surfaces are one of the most importantaspects of our difficult road problems. "Asa member of this very important organisation,which I am certain will perform valuablework, I believe that if we can make the roadssafe for all, and consider the especial needs ofeach section of roadfarer, another great objectof the club will be achieved, Namely animprovement in the friendliness with whicheach will use the roads." Bitterness resultswhen one particular section uses roads to thedetriment of the other.

"There can be no doubt that our road policymust be brought into line with modern trafficneeds. It is useless to plan 'new roads unlessgreat care is expended on the nature of theirsurfaces, with intelligent anticipation as tofuture developments of road policy. TheKingston by-pass is a good example of whatI mean. Originally built as the last word inroads, it had to be reconstructed and wideneda few years later.

" The Government has realised a long timeago that road surfaces are not all that isdesired, for they formed the Road ResearchBoard, with an experimental stretch of roadat Harmondsworth, and a laboratory closeby. It has investigated a large number ofproblems connected with different types ofroad surfaces, the causes of skidding, and thedurability of road surfaces, all inter -relatedproblems, for not only must the surface bereasonably skid -proof, but it must remain sounder heavy traffic conditions and the rapidwear which that brings, and under a varietyof weather conditions.

" These experiments and the conclusionsdrawn from them are made known to boroughsurveyors; but unfortunately the Ministry ofTransport has not the power to compel theiradoption, except in so far as the main roadsare concerned.

" The colour of the surfaces has a verymarked effect upon road safety. We cannotsay that money has been lacking to bringabout many obvious reforms. The RoadFund has produced millions every year, butthe money has gone in other directions,although when the Road Fund was introducedby Lloyd George he said that it would be usedfor no other purpose than the making andupkeep of roads.

"Whether the Fund after the war will revertentirely to that purpose no one can say.But whatever reforms on road surfacts areproved to be necessary money will be requiredin abundance to carry them out. It will alsotake years to bring them into effect."

Other views expressed concerned the colourof roads, whilst Mr. J. A. Masters thought

that a surface which may be good for motorists,such as a rough macadamised surface, was notnecessarily the best for cyclists.

Mr. V. S. Bowman thought that theproblem should be attacked from the tyre

. point of view, and he mentioned that onecompany had produced a method of treatingtyres which made them absolutely skid -proof.

It is not possible here, to report all theremarks and opinions expressed, but they arebeing submitted as a memorandum to theMinister of Road Transport.

The . toast of the Club was proposed byMr. A. Logette, with a reply by Mr. C. G.Grey ; the Visitors and Press were toastedby Mr. F. J. Camm, with a response byMr. W. J. Mills ; whilst the toast of theChairman was proposed by Mr. J. LindsayCallway.

New members of the club include theMarquess of Donegall ; Mr. H. G. Wells(writer of the famous cycling novel, " TheWheels of Chance," which was serialised inthis journal just before the war) ; Lt. -Col.Charles JarrQtt, O.B.E. (founder of the Auto-mobile Association) ; Leonard Ellis (Secre-tary of the R.R.A.) ; Prince Birabonga(famous racing motorist under the name ofB. Bira) ; Col. J. A. A. Pickard, O.B.E.(Secretary of the Royal Society for Preventionof Accidents) ; H. Samuelson (Secretary ofthe R.A.C.) ; Major Frank Bale, O.B.E.(one of the founder members of the Orderof the Road) H. Morgan (Junior Car Club) ;H. Boon (Chloride and Electrical StorageCo., Ltd.) ; W. J. Bassett-Lowke ; TheMarquess of Queensberry ; Sydney Camm(Designer of the Hurricane, Typhoon, etc.) ;and Trevor T. Laler.

The club already has made considerableprogress, and is representative of all sectionsof road users. It hopes to play an importantpart in post-war road policy and to avoidthe clashes which occurred before the warbetween rival road interests. From time totime, the club will issue memoranda on varioustopics affecting the roads and road users,and it will submit them to the Ministry ofTransport.

The club does not intend to work in oppo-sition to existing organisations but to adopt anindependent and helpful policy in its effortsto find solutions to pressing road problems.

When the war is over. we cannot go back tothe old system, and it is a wise move tofound the club during the war when the roadsare comparatively free- from traffic, and tohammer out a policy which will make roadtravel a pleasanter thing than it has ever been.As a national body the Roadfarers' Club willtake its place as the only Roadfarers' Parliamentrepresentative of all road users, fair to all,and not favouring any particular section.

The next meeting of this Roadfarers'Parliament takes place on Saturday, February6th, when there. is to be- a debate on Roadand Vehicle- Lighting. Membership of theclub is by invitation only. The secretaryis R. A. West, 32, Elm Bank Gardens, Barnes,

THE CYCLIST

AG RAM S

12akeLoolors 111111414%

Lights OutTHE city of

automaticplease copy!

Cuikry and CrockeryUSERS of hostels in North Wales must now carry

their own cutlery and crockery.

Map Re -issuedHE youth hostel map of England and Wales has been

re -issued in a revised edition.

New Channel -Paris RoadTT has been reported that the Germans are making a

new 13oft. road from Paris to the Channel.

Ordnance Maps AgainORDNANCE Survey maps, which have been in

short supply, are now'available in greater quan-tities.

To Wales by Bridge?AT a meeting of caterers in North Wales, a road

bridge from the Wirral across the Dee estuaryinto \Vales was advocated.

Surfacing New RoadsMO avoid the use of imported bitumen, experimentsA are being made with quick -drying compressed

concrete for surfacing new roads.

Regular Hostel, WeekendsTHE Scottish Y.H.A. is askjng cycling, clubs to

organise regular youth hostel- week -ends as ameans of keeping hostels open during the winter.

Surcharges Go'QURCHARGES for the use of fuel are being abolished" at youth hostels. The latest areas to drop sur-charges are the South Coast and the West Riding.

More Hostel Users -

DURING 1942 a.total of 31,158 visitors stayed at thehostels of the Y.H.A., Manchester Regional

Group, compared with 24,656 in the previous year.

Cyclists and New Tyne TunnelENGINEERS planning a new tunnel under the

Tyne between Howdon and South Shields aregiving consideration to a scheme for escalators forCyclists using the tunnel.

More London HostelersMEMBERSHIP of the Y.H.A. in the London

Region was 22,760 at the end of the financialyear, compared with 30,875 in 1939, 16,896 in 1940,and 16,199 in 1941.

Stole Vicar's BicycleAMAN who stole the Vicar of Newnham's bicycle

was sent to prison for fourteen days at Hitchin.He was said to have sold the stolen machine to anAmerican soldier.

New Youth HostelsTWO new youth hostels are to be opened in the

Manchester area shortly. 'They are situated atWhitehough Grange, near Barley, close to the famousLancashire landmark, Pendle Hill, and at The Hall,

' Castleton, the Derbyshire resort.

Better Bicycle FacilitiesTHE L.N.E. Railway is to fit bicycle stands at

' suburban and country stations to accommodatethe machines used by passengers travelling to and fromstations. Existing facilities have become inadequate.

"110't -i141;4,

14 1(1111114$

French Prices Con-trolled.

TICH-Y. radio recentlystated that the prices

of bicycles in France are tobe controlled. The controlapplies to both new andseChrid-hand Machines, andto wholesale as well as retailprices. Second-handmachines must not be soldat prices which exceed thosefor new. ones of the sametype.

.44-.4407r,-7-4--"7=240. New High RecordA NEW high membership" record has been madeby the Scottish Y.H.A.During 1942 a total of29,032 members was en-rolled.. Previous figuresWere : 1939, 18,720 (highestpre-war membership); 1940,15,870; and -1941, 21,594 -Most of the newcomers areyoung cyclists.

Bicycle v Tram.at York A BOY who stole the bicycle of a Glasgow insurance

day vlilleecitasr was ourlaisdirnotgintlemachine netthas decided to put out all its" "et:traffic signals. Other towns and cities seized the bicycle and the boy, but, the latter made bff

0n''a tram, only to be followed and caught by theowner.

Rail Vouchers CancelledTHE Ministry of Transport has cancelled the point-

to-point rail vouchers issued to cyclists by thenational cycling bodies, and the youth hostels associa-tions. Members using these vouchers were permittedto travel by rail to one station and return from another.

" Bitterly, Ashamed"AT a meeting of the Town and Country Planning

Msociation in London, Mr. W. H. Atwell, presi-dent of the Royal Institute of British Architects, said :" The ordinary citizen is bittetly ashamed of theslaughter on our roads, particularly of children, anddemands that the new planning shall devOte itselfseriously to dealing with this blot on our national life."

Most Popular Scots HostelOCE again,, LocleEck youth hostel, in Argyllshire,

is the most popular youth hostel in Scotland.During 1942 it had 10,349 overnight visitors. Otherhostels with good attendances were : Creag Dhu (9,466),Glen Loin (9,208), Strone (7,979), Edinburgh (7,745),Fintry (7,330), and Ledard (7,090). All these hostels,except Edinburgh, arc in the popular Loch -Lomond -Trossachs area.

Round the Top of the WorldQENDING his congratulations on the opening of the" new Alaskan -Canadian military highway, Mr.Henry Wallace, vice-presi-dent of the U.S.A., pre-dicted that the new roadwould be " part of aneventual highway servingthe New \Vona from thesouth of South America toSiberia," and went on tosay that in the , not toodistant future it will bepossible to travel overlandfrom Buenos Aires toMoscow.

Famous HostelClosed

DERWENT HALLyouth hostel, opened

by the Prince of Wales in1932, has been closed. Itssite is to be covered by anew reservoir. The week-end the hostel closed, some16o cyclists and hikersheld a party, and next dayhelped to dismantle andpack the hostel's equip:ment.

Increase at ManchesterA T the annual general meeting of the Youth Hostels" Association, Manchester Regional Group, it wasreported that during 1942 the total membership hadgrown to 10,448, an increase of 34 percent. over thepreceding year.

Famous Pilgrimage RecalledraNE of the most famous pilgrimages by bicycle is- recalled by the death of Lady Elspeth Campbell.In 1895 she led a party of Campbells into Glencotin an effort to overcome the hatred which had been feltbetween the Macdonalds and the Campbells since theMassacre ih 1692. Lady lilspeth rode through Glencoeon a bicycle, one of the first women riders to do this.Forty years later,she was a passenger in the first vehicleto traverse the new Glencoe road.

January, 1943

Deserter Steals BicycleAA

DESERTER who stole a bicycle from a Falkirkworks was fined £t recently at a local court. It

' was stated that the man rode the machine to Glasgow,where he tried to sell it, kit the roan to whom it wasoffered was suspicious and notified the police.

Vice-president's Golden AnniversaryFOUNDER member and first secretary of the

Finsbury Park C.C., of which he is now a vice-president, Mr. A. C. Crane has celebrated -the goldenanniversary of his wedding. He is president of theNorth Middx.. and Herts C.A., and'. a member of the1%0:P.C.

A Clubman's Death in Action1190BERT ATTEWELL, Nottingham Wheelers, lostJ.% his life when the submarine on which he wasserving was sunk by enemy action. He was only 21and was winning prizes in road time trials when hewas 17.

Their CenturyrIVER too Sheffield Phcenix members are serving'1/41 with the Forces.

Zenith Wheelers' LossDAVID BURNESS, Zenith :Wheelers and West of

Scotland road and track champion, has died ofwounds in Libya. He served with the H.L.I.

A Good RecordFORTY members of the Fulham and Kensington

section of the National Clarion C.C. are in theForces. Two are prisoners Of war.

Lion Road Club Re-formsAFORMER fairly prominent North London club,

the Lion Road Club, has re-formed. It ceasedactivities two years ago owing to dearth of activemembers.

Clubs CombineDYRAMID ROAD CLUB and Abbotsford ParkA Road Club-both, of Sheffield-are combining .to provide open sporting events during the winter.

Smith Parker's " Tour"QMITH PARKER,. Cheshire Road Club, joint" holder of the London -Liverpool tandem tricyclerecord, is with the Royal Navy. Since his entry he hasmade at least one trip round the world.

In Japanese Hands''JEWS is to hand that Tommy Craigie, Barnesbury1-.4 C.C., who was posted missing months ago, is aprisoner of war in Japanese hands.

No Luck !FIVE members of the Kensington and Fulham

Section of the National Clarion C.C., made an

Seen by the wayside : The Telford Memorial seat, at Westerkirk, nearLangholm, close to the famous roadmaker's birthplace at. Glendinning.

attempt on their club's London -Guildford -Londonrecord. Only two finished and both failed.

A Novel ClubBRITISH prisoners of war in an Italian camp have

formed a cycling club which has become affiliatedto the National Cyclists' Union.

D,F,M. for Leeds Clubman ,

QERGE.A,NT-PILOT FRANK ALLISON, Leeds" Clarion C.C., has been awarded the DistinguishedFlying Medal.

Cumnock RallyATIONAI, conditions permitting, the famous

Cumnock Rally will be held this year during theweek -end June 26-27.


Lord

Around the heelworldBy ICARUS

Kenilworth speaking at the Roadfarers' Club lunch reported on page 25.

B.S.A. and Cut Chain WheelsC. A. (BATH ROAD) SMITH, who fors-" many years has been advocating correcttooth form for chain wheels, and has taken thematter up with many manufacturers, writes :

" After all these years of my claiming thesuperiority of gear ' cut ' wheels, B.S.A.Cycles, Ltd. write me that I have' their fullpermission to inform the Press that theirchain wheels are now gear cut to B.S.I.specification. With such a lead those is nodoubt that the trade will forsake the idea ofstamping out gear wheels. It may be alittle cheaper, but look at all the troublefrom replacement of gears, chains breaking,and discontent generally. The B.S.I. (BritishStandards Institution), formed in 1901 as theEngineering Standards 'Committee, gave thecycle trade all information re Steel RollerChains and Chain Wheels,' and recommendedthe trade to cut the chain wheels. What didthe trade do ? They ignored the blessingsof free advice and said cutting chain wheelswas too expensive. And yet they spent noend of money on B.S.I. services, to which Ihave called attention before. The chairmanof a big company recently wrote me how heenjoyed his cycle trips and how his friendsjoined in them, and all remarked how nicelythe machines ran ! In the July number ofTHE CYCLIST diagrams were given of theseremarkable gears showing how they differedfrom the correct form of tooth form !

" I hope that the other large concerns willgo into the matter, and, as I have said before,the small firms here have a chance of intro-ducing cut' gears to the enthusiastic cyclistswho support them. Start on these clubriders and it will not be long before the word' cut' gears will be on everyone's tongue.I believe ' cut' gears to be as big an improve-ment as the pneumatic tyre was to thebicycle 4o years ago. (I started to cycle onsolid tyres in 188; !) "

The New Lamp Masks

FRANK URRY tells me that the new lampmask for cycle headlamps, which is

supposed to be designed to give more light,is a complete failure. He finds it givesless, much less. This funnel -shape design isthe best the combined Ministries of WarTransport and Supplies can do, apparently.

Road AccidentsTHE number of fatal road accidents

occurring on the roads of Great Britainduring the black -out in October, 1942, hasgreatly increased.

Figures show that out of a total of 697persons killed, 285 lost their lives in the hoursof darkness. In the previous month the totalwas 553, of which deaths during the black -out

only 158.The figures point to the need for greater

caution on the part of all road users. Pedes-trians are again reminded that it is not safeto rely on drivers seeing them. They shouldact rather on the assumption that driverscannot see them. They can also help toprotect themselves by wearing or carryingsomething light in colour.

Drivers are urged to regulate their speedso that they can pull up within the range oftheir vision, and to see that their lamps areproperly adjusted.

The increase of fatal accidents to pedalcyclists in the blackout from 14 in Septemberto 38 in October should underline theimportance of seeing that lights and brakesare in proper working order.

The figures for October contain a warning-but they also contain a message ofencouragement. Deaths in the black -out inthis month since the beginning of the warhave steadily decreased. -They are asfollows

October, 1939-5611940-501

!) 1941-3781942-285

Record PassedLEONARD ELLIS, secretary of the R,R.A.,

informs me that the record claimed byR. Morford, of the South Western Road Club,and G. E. Lawrie, of the Viking Road Club,for the tandem tricycle four-hour record, inrespect of their ride of 2321 miles on July26th, 1942, has been passed by the R.R.A.Committee.

The Cycle and Motor Cycle Trades andthe Red Cross

WORKERS throughout the country arecontributing £5o,000 a week to the

Red Cross through the Penny -a -Week Fund.

A great effort is now being made by industryto secure at least similar regular supportfrom employers.

H.R.H. The Duke of Gloucester, presidentof the Red Cross and St. John Fund, a shortwhile ago asked Sir Harold Bowden, Bart.,G.B.E., to make an appeal to the cycle andmotor -cycle trades; and Sir Harold gladlyconsented to do so. Immediate and enthusiasticsupport was forthcoming from the BritishCycle and Motor Cycle Manufacturers andTraders' Union. An extremely strongcommittee was formed under Sir HaroldBowden's chairmanship, consisting of Mr.Gilbert Smith, Major Frank Smith, Mr.Herbert Goodwin, Mr. C. E. Wallis andMajor H. R. Watling. The committee thusincludes the president and director of theUniOn and the two surviving immediate pastpresidents.

Sir Harold Bowden has sent a letter to alarge number of those engaged in the twoindustries concerned, asking for their generoussupport for " The Cycle and Motor CycleTrades Red Cross Fund."

It is recognised that many firms andindividuals are already supporting the RedCross, and indeed some have contributedhandsomely to the Red Cross Sports Appealrecently directed to those interested in cyclingas a sport. The committee feels, however,that in spite of this fact the cause is sodeserving and the need so urgent that theresponse to this further appeal will beimmediate and generous.

Most of the activities of the Red Cross inwar -time are common knowledge. What is notso well known is that the Red Cross is theonly agency through which parcels, includingfood parcels, can be sent to prisoners of war.In this service alone the annual expenditure is£4,500,000-a figure which cannot diminish,and may be expected to increase as majoroperations develop. On the basis of its currentexpenditure and commitments the Duke ofGloucester's Fund can only just make bothends meet.

A feature of Sir Harold Bowden's appeal isthat subscribers are being urged to contributeannually, under covenant, for the duration ofthe war. The Red Cross, which is exempt fromincome tax, thus obtains double benefit fromeach subscription without extra cost to thecontributor. This Fund is exclusive to thecycle and motor -cycle trades. It constitutesmore than an opportunity to assist a greatcause-it is a challenge to these industries.

Subscriptions or inquiries should beaddressed to The Cycle and Motor CycleTrades Red Cross Fund at St. James'sPalace, S.W. t. Lists of subscribers will bepublished each week in the cycling and motor-cycling press.

N.C.U. Diaries for Members Serving AbroadCLUBS wishing to send a copy of the

N.C.U. Diary to members servingabroad may purchase the diaries in lots ofnot less than one dozen at 2s. per copy insteadof 2S. 6d.

In making application for this concession,a certificate must be sent to the Union,signed by the secretary, certifying that thediaries are definitely required for membersserving abroad only.

Too Much Camouflage

THE N.C.U. has just settled an interestingcase in favour of one of its members.

In some part of England the roads were being_camouflaged with an apparently sticky sub-stance, and the N.C.U. member skidded and

(Continued on page 28)

28 THE CYCLIST January, 1943AROUND THE WHEELWORLD

(Continued from page 27.)sustained injuries. The defence of the con-tractors was ,that he had passed over this roadmore than a number of times and knew thatthese operations were taking place, and inconsequence, therefore, the fault was his.The Union's submission was, however, thatthey had 'no look -out man and no warningnotice, and that their member could notpossibly be expected to conclude that theroad was in a dangerous condition if no warn-ing to that effect was given, and further, thatthe contractors were evidently saving theexpense of a look -out man and in consequencethe cyclist sustained injury. The Union'ssubmission proved to be a good one, anddamages were awarded to the member.

R.A.F. to Get 170,000 BicyclesSIX bicycle manufacturers, have now com-

pleted the delivery of 170,000 standardmachines for use on airfields. Pilots, amongothers, now use them to cycle to and fromtheir aircraft and so save petrol. A proportionof the new machines are painted white forsafety in the black -out. .

Bicycle Thefts in America \

MR. J. EDGAR HOOVER, Chief of theFederal Bureau of Investigation, re-

cently commented on the great increase ofthefts in bicycles and accessories in America.As in this country, when the theft is reportelithe owners are unable to give a descriptionof their machines. Very, few are able to givethe serial number. Many American muni-cipalities have adopted licensing of bicycles,and this has resulted in a reduction in thefts.

Need or Shall?THE Lighting Restrictions Order for 1940

states that it is illegal for any light to be

displayed otherwise than in a roofed building,closed vehicle, or other covered enclosure,and states that in the case of a bicycle itshall display the lights required by the RoadTransport Lighting Act, 1927, which saysthat only a single lamp showing a white lightto the front instead of two such lamps needbe carried. A cyclist was recently prosecutedand convicted because he carried two head-lamps showing a white light. He was fined5s. The case on appeal.was heard in the King'sBench Division, and Lord Chief Justice ofEngland Viscount Caldecote upheld thedecision. Thus, the word need in the Actmeans shall. Yet the same Act states that acyclist wheeling a bicycle after dark may do soprovided he keeps to the left-hand side ofthe road and need not show a light. By in-ference, therefore; this must mean he shallnot show a light.

Notts Centre Massed Start MeetingTHE affiliated clubs of the Notts Centre

met on December 1st, 1942, in Notting-hamshire to discuss the Emergency Com-mittee's massed start circular. The chairwas taken by Mr. Jack Holdsworth, the lateNational Organiser for Cycling, and thesecretary of the Union, A. P. Chamberlin,was present. After a meeting of considerableinterest, any questions were the order of theday, but no proposition desiring an alteration ofthe present rules of the Union was submitted.

N.C.U. Centres and Massed Start RacingUP to date, five centres have held special

general meetings to discuss the Union'smassed start circular. They are :

South Yorks and North Derby;Birmingham and Midland ;London ;Devon and Cornwall ;Nottinghamshire.

The secretary of the Union, A. P. Cham-berlin, has attended all of these meetingswith, the exception of the Devon and Corn-wall Centre, where the date clashed.

All these centres have decided to upholdthe 'present rules of the Union, and noresolution has found favour in which anyalteration of rule has been suggested.

,"Massed' Start MeetingASPECIAL general meeting of the Birming-

ham and Midland Centre was held at theFriends' Institute, Birmingham, at 5.30 p.m.on Saturday, November 28th. Mr. A. E.Taylor Was in the chair, and was supportedby the secretary of the Union, A. P. Chamber-lin. At the outset of the meeting the chairmanexplained that every possible latitude wouldbe given to delegates to thoroughly explorethe matters referred to by the N.C.U. Emer-gency Committee's statement on massed startracing.

At the commencement of the meeting onedelegate expressed the opinion that it was notnecessary for the statement to be read again,because all the clubs should have had theirinstructions as to which way to vote. Thechairman ruled, however, that the statementshould be read paragraph by paragraph, andany questions arising therefrom would beanswered by the secretary of the Union.This was done, and much lively discussionresulted.

Mr. Chamberlin was able to explain everydetail of the controversy from the beginningto the present date to the meeting, and aresolution was moved by Mr. M. P.McCormack : " That the Birmingham andMidland Centre supported the EmergencyCommittee's statement on massed startracing, and agreed to abide by the rules of theUnion." This was carried (delegates onlyvoting) by 27 to 9. -

What the Clubs are DoingRoller Contest for Glasgow ?THE Douglas C.C. is making an effort to hold an

open roller contest in the Glasgow area this spring.

Now C. SIM.ASHBURNER, a founder of the Crawick

A Wheelers, is now a Company Sergeant-Major:n West Africa.

New Scots PromotionsVOR the first time since the club's inception, theA St. Christopher's C.C., of Glasgow, will be

. holding two opens, at 25 -and so miles, this season.

More Scots EventsGLASGOW'S new cycling body, the Belle Stir

Road Club, is -to add to the 1943 list of openevents beholding four time -trials, two for men and twofor women.

Douglas Men in ForcesTHREE well-known members of the Douglas C.C.,

of Glasgow, have just joined the Forces. Theyare James Renwick, Nelson Robertson, and RobertGibson.

Briggs in Scotlandmu ALTER BRIGGS, former C.T.C. official in

Yorkshire, has been stationed in Scotland re-cently, and has made good friends amongst the localcyclists.

Third Man's PromiseJAMEST SCOTT, Crawick Wheelers, 17 -year -old

brother of Bill and David Scott, the South ofScotland cracks, has promised to take time-trialingseriously during the coming season.

More Record Attempts?ThUNCAN McCALLUM and Joe Macrae, Douglas4- C.C., holders of the Glasgow -Dundee -and -Backtandem record of the R.R.A., of .Scotland, have designson ,the Glasgow-Oban-and-Back record.

Scott in. EnglandBILL SCOTT, Crawick Wheelers, holder of the

Scottish 25, 30 and so records, is at presentstationed in the North ofEngland. Although he is acolliery worker, there seems noimmediate prospect of his releasefrom the Royal Engineers.

Shotts Riders Called upFIVE prominent members, of

the Shotts Wheelers, aLanarkshire club, have beencalled up. They are J. ,D.White, S. Grahom; G. Stewart,W. Corbett and A. - Glen.Champion of the club is T.Tucker Brown, and novicechampion W. Corbett.

Not so long ago this little machine was the toy of playboyson one of the beaches of America. To -day it serves a usefulpurpose in London, transporting parcels of hospital essentials.

Scots Star a MinerTACK CONNER, , the youngJ St. Christopher's C.C.,Glasgow, road star, is nowworking at a West of Scotlandcolliery. He registered for theRoyal Marines, but later electedto become a miner. He is nowtime -trials secretary of his club.

Cyclists' Information BureauTHE .National Clarion C.C., Glasgow Section, has

opened a Cyclists' Information Bureau at itsclubrooms at a, Northbum Street, Glasgow, C.4.Members will attend every Wednesday evening andanswer questions relating to all aspects of cycling.

Hundred at Royal Albert GatheringOVER too members and friends attended the annual

prize -giving of the Royal Albert C.C. at Lark -hall. " Lion " of the gathering, was -Alex. Gilchrist,3o -year -old rider who is the fastest man the club hasproduced. He won club championship, as well as theveteran's trophy and the club's open 25.

South Scotland SuccessSUCCESS attended the annual prize -giving of the

Upper Nithsdale C.C., of Kirkconnel, when overtoo members and friends 'were present. Mrs. Wilson,wife of . Lieutenant -Colonel Wilson, presented theprizes, and principal recipients were Alex. Gilchrist(Royal Albert C.C.), David Scott (Crawick Wheelers),and A. Adams (Upper Nithsdale).

Meeting of Scots CyclistsTHE special general meeting of the Scottish Kmateur

C.A. to consider an executive proposal to revertto the 5939 constitution has been called for Sunday,January 17th, at 1 p.m., at Bo'ness, West Lothian.All affiliated associations and clubs are being circularisedby the secretary, Harry Price. The S.A.C.A. is thecontrolling body of road, sport in Scotland, and has areciprocal agreement with the Road Time TrialsCouncil.

Nelson Wheelers DineTHE annual dinner of the Nelson Wheelers C.C.,

held on November 21st at Nelson, Lanes, wasattended by 6o members and friends, who voted theaffair the best of the series to date. Rex Coley (" RaggedStaff ") travelled specially from London to be present,and congratulated the club on its wonderful achieve-ments. Miss Gwendolen Stiff, the " Wheelers' "secretary, who organised the dinner, received a specialcup for her performance in the Bon Amis " too "last season.

Fastest. Mid -Scotland RiderBEST Mid -Scotland cyclist of 1942 is Alex. Gilchrist,

Royal Albert C.C., who broke club records at25 and so miles, with times of hr. 3 mins. 46 secs. and2 hr. IS min:s. 5 secs. respectively.


I Ride in the Hcray CountryBy PETER LINCOLN

The Town Hall, Newtown, Isle of Wight. Originally the old capital town, it is nowjust a quiet, almost forgotten corner of the island. Its old inn, The "Noah's Ark"

(centre) is closed, and the Town. Hall held in trust and used as a Y.H.A. centre.

WE often talk of " local atmosphere "when we are discussing novelistsand the writers of books, and it is

always interesting to the tourist, whether hecovers the ground on foot, or on a cycle, tolinger in a district where an author of renownhas lived, and where places and place-namesmay be linked with books and episodes inbooks: Now, I wonder whether -any authorever put so much- strong and vivid " localatmosphere " into his works as ThomasHardy ? His Wessex novels abound in the" atmosphere " of real places in his belovedDorset, and there is an added interest intouring around in an area which is so closelyand wonderfully associated with a greatwriter. Dorchester, the county town ofDorset, is the " Casterbridge " of the Hardynovels, and the novelist lived in the town forsome years. Now Dorchester is an ancientplace indeed ; in it, we may slip right backto Roman times, and we may see a Romanamphitheatre just outside the town. And ifwe feel that Roman times are too far back forour fancy, then let us take a ,peep at a quaintold building, still known as Judge Jeffreys'sLodgings " on account of the fact that thehouse was used by that fierce and blood-thirsty judge at the period of the " BloodyAssize." Always make a point of looking atany statues in a town, and here in Dorchestersee the one erected to the memory of thedialect -poet of Dorset-William Barnes, whodied in 1886.

We have only to ride out to Upper Bock-hampton to see the birthplace of Hardy-agrand old thatched house which seems afitting place in which such a great interpreterof the village, and the life of rural people,should first have seen the light of day. Bythe way, if you are interested in earth -works,and things prehistoric, slip out some threemiles from the town of Dorchester, and youwill see the mighty prehistoric earth -work ofMaiden Castle, crowning a hill.

SalisburyWe must think of Dorset and Wiltshire

together if We are to get the essential atmo-sphere of Hardy and his work. And we just

cannot be in the Wessex districts withoutjourneying to Salisbury, where the greatcathedral (unique because it is the only oneof our English cathedrals built throughout inthe one style) stands as a wondrous shrine,keeping watch, as it were, over the wholearea. The " one style " is Early English, andthe central spire rises like a finger pointingto Heaiien-a marvellous landmark to thetraveller crossing Salisbury Plain. I knowof no English cathedral which has such aperfect setting as Salisbury-the Close isjust as you would wish a Close to be-peaceful,dignified, with stately houses and an atmo-sphere which breathes beauty above all thesordidness, the clamour, and the cheapnessof the world. The 15th -century " PoultryCross " is something else which Salisburyoffers to the traveller with seeing eyes andunderstanding heart-and if perchance youhappen to visit the " George " Inn, in HighStreet, you may see some interesting 15th -century woodwork.

Blandford is a Dorset town which I love ;it has Georgian dignity and an air of stateliness.There was a great and ruinous fire in Bland -ford in the year 1731, and much was destroyed,but the " Old House " in the Close survivedthe tragedy, and you may still admire itsmoulded chimneys, its red brick structure, andits spreading eaves. Blandford, in the oldendays, was called Blandford Forum, and in theHardy novels it becomes " ShottesfordForum."

Old " Shaston "Let us to Shaftesbury, or to give its old

name, " Shaston." It occupies a wonderfulposition on a hill-a hill overlooking the lovelyVale of Blackmore--of which Hardy gives agreat and moving picture in his " Tess of thed'Urbervilles." It is surprising to thinkto -day that there was a time when sleepy old" Shaston " was a busy, thriving town,possessing a great abbey, a royal mint, and noless than a dozen churches. Only three of thelatter survive, but there are still some remainsof an ancient abbey.

My best memories of Wessex centre. around

old Wimborne, where the Minster is surelyone of the very noblest shrines in our land.Unlike Salisbury Cathedral, one cannot saythat Wimborne Minster offers us one purestyle, for the central tower is Early No/man ;the east end is Early English, while the westend shows 16th -century characteristic's. Butit is not a " muddle "-and one feels that inWimborne Minster one is in a place of hal-lowed stones, of wondrous atmosphere, andthere is a sense of awe associated with theplace which is akin to that one experienceson a first visit to York Minster. In a niche ofthe south choir aisle, the visitor may see thestone coffin of one Anthony Etricke, a manwho imagined that he knew exactly the yearin which he would die. Evidently a man whobelieved in " having everything ready for anyevent" he had his coffin made, and evenwent to the length of having the date inscribedon it-the date 1691. But the great reaperwas tardy in coming for Anthony, and he didnot actually die until the year 1703. So thedate had to be altered on his coffin, and youmay quite clearly see the alteraton to thefigures to -day ! Here in Wimborne Minsterone may see one of those amazing astronomicalclocks-similar to the one in Wells Cathedral.This one at Wimborne is said to have beenmade by Peter Lightfoot, in 1325. The clockis connected to a figure in the wall outside thechurch (like " Jack " at Wells) and appearsto strike the quarters on bells, but I believethat the striking is really performed byhammers which are hidden from view.

" Saudbourne "Thomas Hardy called Bournemouth " Sand -

bourne " and one can imagine that under thenovelist's name the famous place would havebeen just as famous-and gay posters on ourhoardings would have lured us to " Sand -bourne " just as easily, and as surely, as theytempt us to take a " Southern express " toBpurnitnouth, there to bask in sunshine, andto derive benefit from the pine woods, andgaiety from all the amusements which anenterprising municipality provides. But wemust not imagine that Bournemouth hasnothing ancient and historic to offer us;one may seek the quietude and peace of agrey old Norman Priory, in a lovely settingbetween the Stour and the Avon at Christ-church. And Christchurch Priory is a greatbuilding ; its architectural beauty is one ofvery high order ; it stands as a wonderfultribute to Norman builders, and he who ridesto Bournemouth, and fails to ride on toChristchurch, is foolish indeed. There issome particularly rich work outside the northtransept, and the, reconstructed choir, in thePerpendicular style, is wondrously light andbeautiful. The chantry chapels are well worthtime and attention, and there is one built byMargaret Pole, Countess of Salisbury, whowas beheaded in 1541.

WeymouthOur little tour of the Hardy country comes

to a close, but if time permitted we wouldjourney to Weymouth and look long atold Georgian houses ; we would note thefigure of King George III on horseback, cutin the turf off a hillside. We would go toCorfe Castle, between Wareham and Swanage.But we will not forget Sherborne, on thenorthern borders of the Hardy country-andnamed by the novelist " Sherton Abbas."And here we may see an Abbey Church insplendid preservation - showing variousarchitectural styles, from Norman to Per-pendicular. ar

30 THE CYCLIST January, 1943

Before you take your cycle out on tothe road, if only for a short journey,see that your tyres are pumped up hard. 99°/0 of pre-mature cycle tyre failures are caused by under -inflation.Today, every ounce of rubber is precious ! Cycle tyresmust last longer. By keeping them hard when in use youwill make sure of obtaining maximum wear from them.

Got tote hardthese days

fr-----Th/ Repair slow punctures

and renew faulty valve

rubber immediately.

KEEP UP THE

PRESSURErfit331.111t

2/1 323

Cycling in Kent, the Garden of England,you will feel safer on such fulls asCudham with its gradient of one infour, if your brakis are fitted withFerodo Blocks. These brake blocks areefficient in wet or fine, and combinesmooth, silent action and lasting servicewith a wide margin of safety. On suchhills as Cudham . . .

ks

THAT'S WHERE YOU NEED

aee.weatize2t BRAKE BLOCKS


WAYSIDE THOUGHTSBy F. J. URRY

The old church at Wisley, Surrey, ire winter garb.

The Right MethodIHAVE always contested that the majority of bicycles

are over -geared, with the result that cycling can behard work when an autumn wind-or any other forthat matter-goes prowling across the land from thedirection in which you want to proceed. In OctoberI wanted 4o spend a week -end with an old friend ofmine who has turned farmer amid the delectable countrythat lies in' the Clun Valley, amid the highlands ofSalop. I gave myself just six hours of daylight to dothe 6o -odd miles, expecting, or at least hoping, fora mild day of mellow- sunshine, when I- knew thejourney would he a joyful and easy massage. Butthough the day was mild enough,, it was, very muchalive with a nor'wester that flung the leaves of waysidetrees at me as I passed by, and made my passage amatter of circumspect pedalling on a 6oin. gear intothe gale, and taking the slope summits on a 45in.As far as Bridgnorth the wind was pressing my leftshoulder, and the shelter of the hedges was gracious:but I knew that after an early tea in the " Loyal Town,"when I turned into the funnel of Come Vale, that windwould riot straight down the road over which I wasbound. It did. But my little gears kept me going at asteady to m.p.h. without any feeling of weariness, andthe few riders I passed by, struggling with their 7oin.ratios, probably wondered why the grey -headed ridercould make ground so easily. Just full use of the anklescombined with a low gear-only that and nothing more.It was one more lesson-if one were needed-of thevalue of very moderate gearing for ordinary touringpurposes ; 6a Miles of windy riding through comelycountry, and an appetite of marvellous proportion atthe end of the journey.

The Jolly CountryHAT was a glorious week-and spent in the con- -

genial company of farmers, cattle dealers,auctioneers and men of the soil, hard as nails, andpossessing thirsts which made my tea -drinking exploitsseem completely feeble. Another friend of mine,who has recently bought a small estate adjacent toClunbury, took us for a ride on a glorious Sundaymorning over Titter Hill, at the foot of which standthe ruins of Hopton Castle, one of the Border strong-holds. Up we went thropgh the colOured woods, andout among the heather and bracken to the windy ridge,whence the visions of the land from this 1,300 footeminence were sunny, misty pictures of loveliness.This man, who led the way on the most expensive ofbicycles, said theSe were the roads he loved to roam,these upland ways over the top, for this was cyclingwith the flavour of real adventure. When he wantedto go fast in normal times, there was the car for thesatisfaction of quickness ; but it was a soulless businessmopping up miles in a hurried phantasmagoria. Andbeing a nationally noted photographer, he should know.Plums, apples, damsons, mushrooms, nuts-they allcame within the menu of that week -end : in additionto jugged hare, roast partridges, and that speciality ofthe country, grilled ham and eggs. Surely these farmersare working hard in these urgent times, but at leastthey have the solace of good feeding, and the open air.Lucky you will count me, and lucky I am to claim suchfriends ; but when you have been wandering this landon a bicycle for more than half a century, you wouldbe but a poor individual if the spirit of comradeshiphad never strayed outside the immediate hotine circle.Those three days were good, and I will go again in thedays to come.From Over the WaterFOR some weeks now I have been riding an American

bicycle, not the type you so frequently seeillustrated in the press, but a machine built on English

lines, and equipped with English saddle, tyres, brakes,and Cyclo gear. It came about like this. Some monthsago Mr. Frank Schwinn, one of the big cycle manu-facturers of Chicago, U.S.A., and an old friend of mine,sent me a pair of racing hubs and asked me to trythem. I told him I could not get a bicycle worthyof these excellent hubs until the war was over, fndhis response was to send me a frame and fittings (chain -wheel, forks, etc.) which, remarkable to relate, cameto hand a few weeks ago, for to be quite candid I didnot expect it would find travel room. It took me. uitea long time to discover the needed oddments to makea canplete biCYcle,hut my trade friends searched theirstores and 'finally I was fixed up -with an outfit, com-pleted by a Cyclo gear giving 45M., 6oin. and 68in.,through the good offices of Mr. Louis Camillia ofthat Company. It is a beautiful machine, moderatelylight, very easy running, with most comfortable positionand steering. The only special thing about it is that asteering lock is concealed in the column, and with theturning of a Yale key the steering is firmly locked.This is the neatest, lightest and most serviceable cyclelock I have seen, and I unds-stand one of our bigEnglish marers has taken over the British rights ofproduction. This type of safety lock will become veryPopular, for it is foolproof, cannot be tampered with,and is reasonable in cost to produce. The hubs, too,are a very fine job, built forssix days' racing with duralflanges, using short spokes, and the set -out is on thehighest plane. In its first zoo miles of travel the machinehas charmed me.

The .$hort AnswerA MAN who passes me regularly" on the way to work stopped hiscar and asked me why I seem toride a bicycle so easily. In a wayit wa.s'a compliment, but I am afraidmy reply was terse and to the point,for I just said, " regularity, a lowgear, and the best bicycle I canbuy." But considering the matterat leisure, I am not sure that thatimmediate response to the querywas not all that was necessary, forit does contain the secrets :of easyriding, if secrets they be. Howdifficult it is to convince people thatsuch is the case, and I am remindedof the ancient saying that 'advicegratis seldom great is," yet in thiscase it is at least true that if anindivual wants to ride in ease andcomfort he or she must have theright bicycle positioned correctly,and must be in practice-I won't sayfit, because that word denotes someform of athleticism, and that iscertainly not essential to easy riding.I have found from time to timewhen in the company of beginners,that they are too anxious to " getthere," to push on with the fixednotion that achievement is the onlything, and often enough to ignorethe need for feeding. If you wouldride for the sheer joy of travel,achievement is the last thing to beconsidered, just because it will comeall in due course without worryingabout it ; but feeding-susteriance-is important, and should not beignored, because curiously enoughone does not feel hungry whencycling, but when one does eat is

frequently surprised at the quantity of food necessaryto assuage appetite. If people will only grant themselvesan intelligent approach to cycling, they will be mostagreeably astonished how much cycling has to offer inreturn. It grows on you : its healthiness, its freedom,and its individualism.

The Terse Response'THE pity is that to -day we cannot buy the very best+ type of bicycle, unless we are lucky enough to pick

up a second-hand machine of our size and kind ; andthat indeed is the beat way of bicycle buying now.But such machines are not easy to obtain, for ownersknow their worth as articles for their own pleasureand convenience, and are not keen to sell even if theythemselves are unable to constantly use them. .1know numerous lads in the Forces who could obtainextraordinary prices for their machines, but will notpart with them because they want their service andpleasure when leave time comes round. I know, too,an old cycling acquaintance with a real love of thepastime and the posselsor of several high-class machines,who is also a golfer, and a fellow member of his clubasked him to sell one of his mounts. " Right," saidhe, " you can -have one, but I'll choose it." " Howmuch, the would-be cyclist asked. " Seventypounds," was the staggering reply, " and remember Ihave not asked you to buy it. Three years ago Itold you to buy a bicycle, the best you could get,and you laughed at me, and said I was a cycling crank.Perhaps I am, but at least I am travel free to -day, withthe best possible piece of machinery of pm -war vintageunder me." .1 cannot record what the other fellowsaid, and perhaps it is as. well. If you are fortunateenough to have a decent machine, that true little taleis worth remembering, for until the war is over thebest type of bicycle will not be obtainable, and, if Iread the signs aright, even the war -time utility typeare most difficult to get. Therefore, take care of yourproperty ; keep the tyres decently hard, the bearingsadjusted and lubricated, and you have a jolly goodservant with which to go roaming.

This Fine Thing'THERE is another thing I should like the world to

know in reference to this cycling business, andit is just this : There are still among the public somepeople who think cycling is beneath their social dignity.Why, heaven knows, but there it is. I can understandpeople not liking cycling, but for the 'life of me -Ifail to realise why it should be considered infra dig.The simplest method of mechanical locomotion cannotbe infra dig.; and to hold such an opinion seems tome a form of snobbery utterly unworthy. After all,let us consider the matter objectively. Certainly thebicycle was the great emancipator in the sphere of roadtravel for both men and women, and it did more tobreak down old-fashioned prejudice than any othersingle movement. It was the forerunner of moderntransport, and linked country to town at a time whenboth were in danger of isolation, and were beginningto forget how dependent they were on each other. Itopened wide the door to a deeper and truer sense ofunderstanding and encouraged a love of country thatno patriotic platform could ever hope to equal. Noris the pastime in any whit diminished because it haslost its one-time domination in speed ; for it is stillthe most silent and healthiest manner of travel, possess-ing a freedom that has no compeer. When you hearanyone traducing cycling with the unconscious snobberyof the thoughtless, tell him these things because theyare true, and do not be afraid of his self -acquiredsuperiority, for you can be quite sure he is a veryordinary mortal with no more sense than to see himselfas he would wish others to see him.

An Egham greyhound owner gets over his transport difficulties.He used to take his dogs by car, but owing to petrol shortagehe now takes them for a ride to the track in this cycle -drawn

ambulance.

32

we/ /zee e ,3-/W,e?

My Pointof View

St Mary 'Ks e Vitgirk.

Optical DelusionAREAL live knight, in a letter to The Times, suggests

that all military vehicles be fitted with rearreflectors, so that, when " standing stationary " (sic)without a rear light, their existence might be indicatedto other drivers. But one always understood thatthese reflecting deices cannot be seen, despite thefact that they are extensively used on telegraph poles,kerb -stones, roadside signs, and advertisements.Possibly; however, it is only when fitted to cycles thatreflectors become invisible-a sort of optical illusion-or delusion !

" Closed"T T is anew and unpleasant experience for cyclists toA be greeted with a notice -board bearing the word" Closed," when they roll up to a familiar tea -housein the country, with the confident hope of being able,as usual, to obtain a well-earned meal. In someinstances the arrangement is only temporary, arisingprobably from the necessities of shopping not aneasy matter in these days, so I am told-and no doubtit is a case of " business as usual " in a few hours'timer when the caterer has returned front the ordealof confronting rude shop assistants, and hearing aheavy burden of purchases. That circumstance,however, is small comfort to the hungry cyclist, whosefirst impulse is to gnash his teeth. (His second impulse-much more practical, this !-is to decide on thenext step, so that the urgent requirements of the innerman can be dealt with.) On a bleak November Saturday,after doing a substantial mileage whirls had made meready for tea, I drew two blanks from familiar housesof call, each of which displayed the forbidding message

Closed " at the front door. Fortunately, there wasa town within two miles, an my hope of being suc-cessful there was- quickly realised. Nevertheless,there are grim possibilities about war -time cateringconditions, and, having these in view, I seldom venturefar afield without arming myself with an iron ration,comprised of either chocolate or cheese.

More About TyresDOSS IBLY another word or two may be prOfitablyA said on the subject of tyres. The need for adequateinflation is being strongly emphasised by the manufac-turers, and I am in -full agreement. It appears that a'very- high percentage of tyre troubles arises from under -inflation, but I do not think that much can be done aboutit, seeing that an equally high percentage of cyclists isquite unconcerned-and never sees the cycle press,where tyre advertisements are published, What Ideem to be a typical case of under -inflation was broughtto my notice the other day, when a friend arrived at myhouse for tea. She came per cycle, and, as I put hermachine away, the flabbiness of the tyres attracted myattention. Permission to inflate them correctly wasreadily given-it would have been taken in the absenceof assent !--and the visitor ultimately went honkriding on hard tyres, thus gaining comfort and greaterimmunity from punctures, while my good samaritanaction would help to prolong the life of the tyres.

Another point in connection with this matter is theneed for a regular examination of tyres, not only in orderthat penetrating foreign bodies may be removed beforedamage is done, but also to watch for wear. Twicerecently my system of examination has saved me from-well, there's no knowilig, but I visualise a front -tyre burst at speed with disastrous results, or a cata-strophe in either tyre occurring at a particularly awkwardmoment. When contemplating the purchase ofrenewals along the road-and it is well to recall that aburst tyre may mean the obtaining of a new tube aswell as a new cover-one should bear in mind that theposition of affairs is not nearly so favourable for cyclistsas in pre-war days. For one thing, there is a shortageof tyres. For another thing, some of the garages, etc.on which we could depend for supplieS have closeddown " for the duration." Additionally, when troubleoccurs -in the black -out, the early suspension of businessis a factor of vital importance. There is a fourth point

which specially affects a cyclist of my type : I ride in

WAYARE12#eced'

outlandish places where a breakdown would beextremely annoying. Inability to use mybicycle; lack of public transport; absenceof putting -up places-I would indeed bebunkered, and my reputation for punctuality(I usually travel without a time -margin)would be a thing of the pasta So thatthere is a lot to be said in 'favour of givingperiodical attention to one's tyres. It isa policy which pays.

Those Friendly Lights .

NE portion of Mrs. Roosevelt's recentO B.B.C. talk was calculated to strike theimagination of cyclists. Referring to the hlack-but,which she described as " total," the .speaker saidthat " the countryside loses all that friendly feelingwhich twinkling lights that shine out of a window giveyou at you walk along a country road in the dark.Here% country road is dense blackness. A paisink caris a black object with two tiny lights.; This is aquality of blackness which no one who ha% not

' known it can possibly imagine." Mrs. Rooseveltwas apparently lucky enough not to meet Ai, of themotor -cars which are again carrying dazzling lights ;and it is well to remember that the normal cat-di/ion ofa country road, per se, is velvet black. (I gather thatthere are actually neople in this land who, in days ofpeace, would like to have bilious and other flood-lighting applied to all country roads. May Mad dogsbite such people I)'

We night -riding cyclists are conscious of having lostthose friendly lights which shone out at us al we

THE CYCLIST January, 1943travelled through the darkened countryside .in pre-wardays-or, rather, nights. The lonely cottage with itssquare of light-sbmetimes unscreened, sometimescovered With red or white blind-always made a friendlysignal to us ; and, as we melted into the darkness, wemight idly fancy the little family gathered round the

"fire, talking over the day's work, or reading the news-paper, Or listening to the radio. Now and again, whenthe curtain viral not draWn, we might catch a glimpse ofthe cottage interior, with the firelight dancing on thebeamed ceiling, and a distant voice singing " Love'sOld Sweet Song," or some other favourite that provokedmemories. Friendly ? Yes, very.

'And then there was the little cottage which you wereaiming to reach in the hope of being able to' obtainaccommodation for the night. You had not booked, andyou had been delayed on the way. You recalled that theywere early goercto-bed at that cottage. If no lightshone through the night as you approached, then thepeople of the house had retired, and you would have toseek elsewhere for supper, bed and breakfast. Theproblem would be to know where to try your luck, and-alt ! thank Heaven ! a friendly square of light glowsthrough the darkness, and you know that all is well.Yes : we cyclists miss the greeting of the " twinklinglights that shine out of a window," with all the friendlyfeelings they appear to connote. But these days of gloomwill pass, and, in happier times that are yet to be, weshall see the welcoming square of flame, and the fire-light dancing on the beamed ceilidg, as we speed by inthe blackness of the night.

Return to DutyWHAT a joy it has been recently to see some of our

signposts back on the job, and " doing theirstuff " ! It is a sort of homecoming of old friends-friends to whom we invariably give a passing glance,notwithstanding the fact that we are travelling infanailiar country. They are friends we have greatlymissed, and it is good to know that a small selection ofthem have now returned to duty.

ExplanationNEWER readers may welcome a little word of

explanation with regard to the picture which sooften ornaments the heading of my contribution onthis page. The` matter' is simple. On the borders ofNorthamptonshife and Oxfordshire are three finechurchea which are said to have been built by threebrother's. An' antiein adage speaks -of " Bloxham forlength, AdderburY for strength, and King's- Sutton forbeauty." Incidentally, these churches, which arequite close together, are well worth inspection.

Notes of a HighwaymanBy LEONARD ELLIS

Wherefores of White HorsesT OFTEN wonder why so many of the celebrated hillA carvings of Britain, are congregated in Wiltshire.Assuming that the necessity or the desirability ofeffecting these monuments has been estaWshed, it isobvious that certain characteristics are necessary inchnosing the site. -The slope of the ground must lenditself to the presentation of these pictures in semi -elevation. To carve them on the flat would be merelyto present the birds with a fine view,of mari!s handiwork,and there was no thought of aerial observation in thosedays. The ground. therefore must offer smooth slopesof about 45 degrees; steeper than this would probablymilitate against the success of the project as sereeswould form and constantly obliterate the outline. 'Theabsolute (vertical is of course ideal from a visibilitypoint of view, but in the first place enormous exendi-ture,would be necessarS, to erect the scaffolding in orderto reach the job at all. The vertical would also befar easier from the point of view of plotting, and Isuppose that few people have ever stopped to thinkof the diffictilties in the way of laying out one of thesegiants. It is impossible to stand well back and drawthe outline ; the designer has to work at a an& thatgives him no view \ at all of the rest of his work. Hehas also to bear in mind that the figure when carvedwill not be viewed 'fiorn an angle of qo degrees, butacutely, and as a consequence he must distort theoutline so that, the distant viewer will get a reasonablyaccurate picture of what he is trying to portray.

Further ConsiderationsQO much for the contour. It is obvious also that one

L-1 other consideration must weigh- heavily with thedesigner. He must choose a spot where, havingremoved the top layer of turf, he will expose a subsoilthat will permanently offer a sharp contrast to the greengrass. Chalk hills are therefore the obvious answer.We tan see that Wiltshire is as suitable as anyWherein England, but it is by no means the only county,In fact, it is not the only place in which carvings arefound, as there are instances in Bucks, Sussex, Dorsetand Berks. There are probably others, and in all oasesthe same set of circumstances applies. But why somany in Wiltshire I do not know the answer, andcan only assume that the power of suggestion andimitation had something to do with it. We may findan answer in the reasons that led to these carvings,and in considering this we may divide our figures intothree groups.

Genuine Antiquities and Others'(`HERE are first of all the real antiques, then the

numerous memorials of 200-300 years ago, andlastly the efforts of our soldiers seeking relaxation

during the int4-18 war. The first class cannot beMistaken. It contains the oldest of them all, the oneon the Berkshire downs overlooking Uffington. Thisis supposed to date back to the Iron Age, and theoutline is so crude that, although called a horse, it mightbe anything froth a snail to a whippet. By reason ofits design we Cannot dcgibto.. that the giant of CerneAbbas is very old. Whiteleaf and Bledlow Crosses inBucks 'go back to the days of King Alfred, and com-memorate battles with the Danes. The Long Man ofWilmington, in Sussex, althOugh outlined with whitebricks -in 1874, is generallY supposed to be very ancient..The Wiltshire carvings'are nearly all in the secondclass, except that the Britton Horse,*near Westbury,is the oldest and may' gb back to Alfred's days. TheCherhill White Horse was cut in 1780; MarlboroughHorse was made by boyS of the scnool about too yearsae,.. The one at Alton Barnes was executed in ifita,

'and the figuiq near Broad Hinton is alsci comparativelyrecent. in this same class we may put the equestrianfigure overlooking Weymouth, as this commemoratesthe visit of George III.

Cherhill Witite Horse, Wilts.

.00

ELECTRADIXBARGAINS

HANDCOMBS- -Govt. AC -metal Field Hand -

combs, Micro -telephones erTransceivers for portable orfixed telephones. These arethe famous No. 16 Hand -comb, used in.so many fieldsets. Sturdily built withmike finger switch. Brandnew with .4 -way cord, 111/-.Limited number available.

handeombs less centre switch anduo cord, 7/6. 4 -way Cords. 2(6. A HomeGuard can make a compiete pocket tele-phone with these, a mike transformer andbuzzer with a torch battery.PLUGS AND SOCKETS. Radio twin -

Belling type midget socket and plug.Cd. pair. Sockets mounted, 476 sloe. pairs.5 pair strip panel, 3/, 5 -pin plugs, withpanel socket and cords, midget type, 4/6pair. 14 -way plug and socket with cord,7/0. 1-in..Aluminiuni Panel, drilled 13 -in.x 3/-. Bakelite ditto, ;NIL x

2/3.MICROPHONES. Metal -

clad mikes, can beused as they are, or in case,5/-. Mike Buttons,specially selected (as illus-trated), V&

UZZERS,etc. AL Mains IbIzzers for

6 volts, A.C. House Bell, 6 to 8volts, 2.1in. gong. gia. Compirtation A.C.Bell and Mains Transformer, 74T76. Prac-t ice 'Buzzer, Bakelite case, 5/-. Squarebrass case, 4/8: Heavy -type Bakelitecase, 5/6. Dill double core /matt -woundBuzzers, less contacts, 53 The famousTiny Townsend Buzzer, it,MAGNET& The Wonder Midget 2 oz.

Permanent Magnet. Discs of AlniSteel. Tremendous magnetic, Mree aridonly 13/16in. dia. by 1in. thick with softcentre for drilling. One leaps off the tableto meet another. Uses : Any magneticduty, metal separation, magnetic chireksand lifters. Cur -out i-ore,solenoid cores, headphone reinagnet izers,etc., 216 each or 4/0 pair.

TURNTABLES. 'take-lite, 4kin. dia-

meter, steel till bear-ings, 2/- post paid.

CHUCK JAWS (new). 100 sets of 3 -jaw,self -centring Cushman type scroll.

Three sizes, 21in. set td 3 jaws, Bi-.; 3in.jaws, 8/- set. Size 4in. jaws, 10/-, set ofthree.

2/6 RHEOSTATS to 1 Outland-fifi off, carries 4 amps for any

current regulation sub -circuit bat-tery charge or for dimming on 6to 12 volts. One bole fixing withplated bracket for tattle or rack.Translucent .pull -oft knob hasbulb socket. U.S.A. make. Newin carton, 2/6. Well worth 5'-.

ryYNAMO BAMIAINS. Hot ax, 6-12-" volts, 8( amps., D.C., 3rd brush size.sin. x 41in., 1111i., cost £10, unused, 1T/0(carriage paid England and Wales). B.E.C.Double -current Dynamos, 6 volts and 6(10volts, ball -bearing, 1.71bs., new, 27/8(Carriage paid England and Wales).CIRCUIT BREAKERS, ironclad ; any- amps. from 11 to it amps., 25/,Mains Contactors, 35/-. Auto -cutouts Instock.AC. SLOT HOUSEMETERS for shillings:

new Chainberlain and Hookham, 10amps. for fuel controlling.

PUMPS.Stuart. motor pumps, centri-

fugal C.D. sheltet. 12 volts D.C. or230 volts A.C. in stock. Twin -pistonpumps with or without, motors, for sudsor Water. Nevi Beresford centrifugalcoupled tp h.p. A.C. motor, 1111. suctionam delivery, 300 gals. per hr. on 40ft.head, 217/10/,WATER- TANKS for engines, storage,

1`.1 etc. 1r kW. Stuart galvo iron, .

1114, 14iti.Clia., with, pipe unions; only 40; -.

Small oil or suds tanks, square,TANKS.plate, 6Iin. x 3M. x lin., 1/6, post 641.

Welded steel, - high press.. containers forliquid gas or refrig., pint size, 81in. xnew. Make good model boiler, 3/6, post 6d.Please add postage .on -all meil.orders, andgent- stamped envelope for replies to

enquiries.

ELECTRADIXRADIOS

19, Broughton Street,Battersea, London, S.W./3

Al.zeaulay 2159 aimmins

YOU CAN TIN ANY METAL QUICKLY AND EASILYwith

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JUST CLEAN THE JOB AND FOLLOW DIRECTIONS

Heat the work and just sprinkle the powder evenlyupon surface to be tinned. The flux should " boil "and its cleansing action will be assisted if the surfaceis scrubbed with a wire brush at this stage. Whenflux has all melted and the surface is tinned evenlyall over, remove from heat hnd wipe with a clean rag.

Price 6f- per II). nett carr. paid.HOYT METAL CO. of CT. BRITAIN, Dept. PM, DEODAR RD., PUTNEY,

LONDON, S.W.IS

RATCHET & REVO-LUTION COUNTERS

For Range of ModelsSend For Leaflet 18 2

B. & F. CARTER & Co., Ltd.BOLTON, 5.

WILL TEACH YOUTO PLAY THE PIANO

Without Drudgery. Fatigue orhaat% Even if you are ofmiddle age and do not knowa note. San -clear, fascinat-ing Mom* ustng ordinarymusical notation, 110 fr.kishmethods. BY POST, in yourhome, making failure impos-

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MR. H. BECKERBritish by Ibir to and Deseent,

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ESPERANTOBLAZES THE TRAILTO INTERNATIONAL

UNDERSTANDINGand everyone knows hownecessarythis will be after the war.

Esperanto is the international auxiliarylanguage already in wide use throughoutthe world. It can be learned in afraction of the time required for anyother language. A correspondencecourse, including textbook and cor-rection of exercises, costs only St-.

Write to -day for full particulars.THE BRITISH ESPERANTOASSOCIATION, INC., Dept. P206,

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SCALE BUILDING PAPERSFOR ALL LINESIDE STRUCTURESGauge Uo or Gauge (I, state which required. Sheetof General Railway Station Notices, 6d. Sheet ofDoors, Windows, ed. Slate Roof Sheet. ConcreteBlocks. New Brickwork. Window Paper (Black orSliver). Red Tiles. English Bond Brick. YellowAbble. Old Stonework. Smoky Brickwork.Red Freestone. Bovril Adverts. (20 different).3d, per sheet. POSTAGE 1-11 Sheets 21d. extra.

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MATRICULATION&Naps/Jaws,P-exelWhatever your age, you can now

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MINIATURE PETROL ENGINES forAeroplanes and Snead Boats.

Send 3d. for particulars.

COPPER INSTRUMENT WIRE32 S.W.G. Double Cotton Covered. 9'- per lb.34 S.W.G. Double Cotton Covered, 10.6 per lb.36 S.W.G. Double Cotton Covered. 12/8 per lb.30 S.W.G. Enam. and D.C.C.. 8/11 per lb.2;25 S.W.G. Enam. 8> D.C.C. Twin, 5/10 per lb.28 SAV.G. Double Silk Covered, 7/6 per lb.40 S.W.G. Doodle Silk Covered, 21/- per lb.42 S.W.G. Single Silk Covered, 19:8 per lb.45 S.W.G. Single Silk Covered, 36'8 per lb.46 S.W.G. Single Silk Covered, 454 per lb.L. WILKINSON. Reels, ed.. postage 7d.204, Lower Addiscombe Rood. CrossiGW.

GOLDEN HINDA SHEET OF DE-TAILED DRAWINGSWITH DIRECTIONSTHAT WILL EN-

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WANTEDANY Dix, Dublo or Marklin 00 railway

purchased. Every offer acknowledged.-Box 139, cio " Practical Mechanics,"Tower House; Southampton Street, Strand,London, W.C.2.

It's as easy as A B/ C

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