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the symptoms makes it certain that the spinal cord isdiseased, although, of course, such a view does not excludea concomitant morbid condition of the peripheral nervesand of the muscles. The existence of a lasting alterationin the function of muscle, depending ultimately on somenutritional derangement, is shown by a change in the elec-trical and mechanical irritability, as well as by the experi-mental facts adduced by Drs. Ringer and Sainsbury, showingthat even after the nerve terminations are paralysed bycurara, a condition of muscles similar to that which occurs inThomsen’s disease may be produced by certain drugs. But,on the other hand, the symptoms in the case point to analteration in the action of the motor cells of the cord. Itmust be remembered that these cells, even when themuscles are at rest, are still active, as the tone and theadjustment of the muscles must still be provided for.When the call to voluntary activity comes from the brain,this voluntary excitation subdues, as it were, this more orless automatic activity of cells, but in conditions likeThomsen’s disease it may be supposed that this automaticactivity persists temporarily, in spite of the will, yieldingafter a time ; yet in the case described in this paper, thewill was unable, even after a time, effectively to counteractthe condition. The persistent condition of the muscles, thehardness and tenseness may conceivably be the result ofprolonged disturbance of the action of nerve-cells, a viewwhich receives support from the fact that Thomsen’s diseasesometimes shows itself in adults, and in most cases is

slowly developed.’ 1 -

NEW SYNTHESIS OF TARTARIC ACID.

SOME light on the natural formation of tartaric acid isafforded by the recent discovery of a simple way in whichthis acid may be synthesised. A French chemist, M.Genresse, starts with glyoxalic acid-an acid found in

gooseberries, grapes, and other fruits-and acting upon itwith nascent hydrogen liberated from a mixture of zincdust and acetic acid obtains eventually tartaric acid, or

rather the optically inactive form of it known as racemic

acid, equal molecules of the dextro and laevo varieties beingapparently produced. The explanation of the action is verysimple. Two molecules of glyoxalic aeid are merely broughttogether by two hydrogen atoms. Glyoxalic acid is

C2H2Og, while tartaric acid is C4H606, a formula which, aswill be readily seen, contains two molecules of the formeracid joined together by two atoms of hydrogen. It ’iswell known that oxalic acid, C2HzO4, is formed most readilyin vegetable tissues, and is closely related to glyoxalicacid. Having regard, therefore, to the reducing ten-

dencies which are known to characterise" chlorophyll, it isnot improbable that the natural building up of tartaric acidmay be thus explained. --

COMPULSORY VACCINATION IN BOMBAY.

WE have already had occasion to notice the creditabletone of the discussion on the second reading of the Bill forsecuring compulsory vaccination in the Bombay Pre-

sidency, as it has long been secured in Bombay itself. The

only difference which arose was on the part of thosewho think that some great risk lurks in arm-to-armvaccination as involving the transmission of objectionablediseases. They objected to the clause which gives authorityto the Governor-General in urgent circumstances, and,where animal lymph cannot be obtained without dangerousdelay, to authorise the use of human lymph. The chiefexponent of this objection was the Hon. Mr. Javerilal W.Yajnik. He was well answered by the Hon. Mr. J. R.

Naylor and others, who declared that there had been nocomplaint of the action of human lymph. Mr. Naylor,in particular, said that in thirty years’ experience of

litigation and complaints of all sorts in the Mofnssilno complaint of this kind had come within his knowledge.The Governor, however, and his colleagues had no difficulbyin suggesting a modification of the clause, common to thisBill and the Bill of 1878, for Bombay itself, authorising thegovernor to panction the use of human lymph with whichMr. JaveriIalW. Yajnik expressed himself as quite satisfied.It had reference to the provision of regulations as to the sourcefrom which the lymph is to be obtained, and the meansby which its purity is to be maintained. This littledifference being adjusted, the adoption of this beneficentBill was practically settled, and a lesson was givenin reasonableness to less enlightened opponents of suchlegislation at home. While we are confident that the

dangers of arm-to-arm vaccination are greatly exaggerated,it is interesting to note that in Bombay for fourteen orfifteen years it has been found practicable to conduct publiccompulsory vaccination with calf lymph alone.

THE DANGER OF COUNTER-IRRITATION INLOCALISED TUBERCULOSIS.

ACCORDING to Parrachia Anacleto, counter. Irritation inlocalised tuberculosis is attended with great danger. Miliarytuberculosis spreads so rapidly from one organ to anotherby way of the veins and lymphatics that any irritation setup at the seat of the primary mischief cannot fail to increasethe tendency of the disease to become general. Four caseswhich have recently come under his notice show this in aremarkable degree. Tuberculosis progresses slowly, but itallows of no violent remedies, and, he thinks, until somemethod of treatment more successful than either the injec.tion of tuberculin, or cantharidateof potash, or the applica.tion of blisters has been discovered, the danger of causinggeneral infection by their adoption will still remain.

THE DOUBLE CYANIDE OF ZINC ANDMERCURY.

solution ot zinc suiptiate is aaaea to a solution or mercuric

potassic cyanide, or when mercuric chloride is added to asolution of zincic potassium cyanide, a white precipitate isformed, which does not consist, as stated, of a doublecyanide of zinc and mercury of the formula ZnHg (CN)4.Further experiments, an account of which was given by Prof.Dunstan at the meeting of the Chemical Society on the17th ult., indicate that this precipitate is in many respectsa remarkable substance. The quantity of mercuric cyanideretained is dependent on the amount of water presentduring precipitation, as well as on the proportion in whichthe salts inheract ; the maximum quantity retained is 38’5per cent. Zinc cyanide, having this percentage of mercuriccyanide attached to it in such a form that it cannot be re-moved by ordinary washing with cold water, is precipitatedwhen cold saturated solutions of the two salts are mixed in

equimolecular proportions. A series of experiments, in whichthe masses of the interacting salts were varied, proved thata compound of the two cyanides is formed, and suffers

decomposition to a greater or less extent, depending onthe relative amounb of water present. Examination led

subsequently to the inference that the composition of thedouble salt is expressed by the formula Zn4Hg(CNho’Such a salt contains 40’6 per cent. of mercuric cyanide. Itcannot be obtained pure, since it is decomposed by water,and it can only be produced by precipitation of aqueoussolutions. All attempts to prepare the double cyanide bymethods other than that of precipitation have failed.There was no forthcoming evidence of the existence of anyother compound of the two cyanides than that described,nor could sny similar compound of zinc cyanide with othermetallic cyanides than that of mercury be obtained. It is