1 64 



NATURE 



[June 6, 1878 



and if t be the time occupied, T the absolute temperature, p^ p^ 

 the pressures, and a and y3 constants, they find that— 



t=aT(T + ^V 



Chemical Society, May 16. — Dr. Gladstone, president, in 

 the chair. — The following papers were read : — On the detection 

 and estimation of free mineral acids in various commercial pro- 

 ducts, by Peter Spence and A. Esilmann. The method is based 

 on the fact that peracetate of iron even in dilute solutions has a 

 distinct yellow colour, not perceptibly altered by acetic acid or 

 solutions of persulphates, but instantly bleached by free sulphuric, 

 hydrochloric, and nitric acids. The solution is made by dissolving 

 ten parts of iron alum and eight parts of crystallised acetate of 

 soda in 1,000 parts of 8 per cent, solution of acetic acid (25 per 

 cent.). — The action of hypochlorites on urea, by H. G. H. 

 Fenton. The author has found that when urea is acted on by a 

 hypochlorite in the cold, in the presence of a caustic alkali, only 

 half the nitrogen is evolved. From various experiments it was 

 proved that the nitrogen remains behind as a cyanate. — On the 

 behaviour of metallic solutions with filter paper and on the 

 detection of cadmium, by T. Bayley. The author has investi- 

 gated the action which takes place when drops of metallic solu- 

 tions are placed on filter paper, the extent to which the splutions 

 spread being tested by sulphuretted hydrogen. In some cases 

 the solution seemed to concentrate itself in the middle, in others 

 round the edge of the spot. Dilution, temperature, and the kind of 

 filter paper used, have an important influence on this phenomenon. 

 The salts of silver, lead, &c., when moderately concentrated, give 

 a wide water ring containing no metal, while the salts of copper, 

 nickel, cobalt, and especially cadmium, must be much more 

 dilute to present the same appearance. This property of cadmium 

 to spread itself over the whole drop is so marked that it affords 

 an elegant means of detecting it in the presence of metals whose 

 sulphides are black. — On essential oil of sage, by S. Siguira and 

 M. M. P. Muir. The oil consists mainly of two terpenes, one 

 boiling at 152-156° the toher 162-167°, an oxidised liquid and a 

 camphor. — A small quantity of absolutely pure sage oil has been 

 examined, and consists mainly of a terpene boiling at 264-270°, of 

 a dark emerald green colour. — On the action of bromine upon 

 sulphur, by J. B. Hannay. The author has investigated the 

 evidence as to the existence of any compounds of these two 

 elements by boiling points, the spectrum of the vapour, specific 

 gravity, and vapour tension. He concludes that the action of 

 any quantity of bromine or any quantity of sulphur is an action 

 on the whole mass and not in multiple proportion, but that if at 

 low temperatures the compound containing one atom of sulphiu: 

 to two of bromine meets a body with which it can form a mole- 

 cular combination, eg., arsenic, it assumes the crystalline form 

 in conjunction with such a body.— On the determination of high 

 boiling-points, by T. Carnelly and W. C. Williams. The 

 authors have determined the boiling-points of various substances 

 by observing whether or not certain salts fuse when exposed to 

 the vapour of the boiling substance. The melting-points of the 

 salts have been determined by Carnelly. The salts are contained 

 in capillary tubes. — On high melting-points. Part IV., by T. 

 Carnelly, D.Sc. The author has perfected his (specific heat) 

 method of determining melting-points, and eliminated two 

 sources of error. In the present paper he gives the melting- 

 points of over one hundred substances. He promises a paper em- 

 bodying theoretical results deduced from the above observations. 

 Paris 



Academy of Sciences, May 27. — M. Fizeau in the chair. — 

 The following among other papers were read : — On the produc- 

 tion and constitution of chromised steels, by M. Boussingault. 

 This memoir gives experiments proving that chromium, without 

 the presence of iron, does not communicate to pure iron the 

 properties of steel ; analyses of cast chromium steel ; experi- 

 ments on the temper, and resistance to shock and traction, of 

 chromised steel ; mode of preparation of it and ferrochrome, &c. 

 — On the action of anaesthetics on the respiratory centre and 

 cardiac ganglions, by M. Vulpian. In chloralised dogs faradisa- 

 tion of the upper cephalic segments of the cut vagi stops the 

 respiratory movements just as in dogs not ansssthetised ; but 

 whereas, in the latter, the respiration in general easily and spon- 

 taneously commences again, spite of the electrisation being con- 

 tinued, it is not so with the former, and the animals die unless 

 electrisation be stopped and artificial respiration be produced, 

 aided, it may be, by energetic faradisation of the trunk. The 

 heart, too, may finally stop in such a case. M. Vulpian thinks 

 this explains certain accidents in clinic ancesthesia. — On the origin 



of the excito-sudoral nerve-fibres in the sciatic nerve of the cat 

 by M. Vulpian. Those in the abdominal cord of the great sym- 

 pathetic come from the spinal cord, chiefly by the first and 

 second lumbar nerves; but there are others, and more, which come 

 directly from the spinal cord by the roots of the sciatic nerve. 

 An analogy with the nerves of the salivary glands is indicated. — 

 M. de Lesseps gave details of the pacific conquests, made in 

 the name of the Khedive of Egypt, by Gen. Gordon, and quoted 

 from an official Egyptian report on Capt. Burton's recent im- 

 portant discoveries in Arabia. — Transparent hydrated silica and 

 hydrophane opal, obtained by action of oxalic acid on alkaline 

 silicates, by M. Monier. The experiment should be made with 

 500 to 600 grammes of silicate of 35° or 40° B ; the oxalic acid 

 is diluted to only four degrees. Letting the acid act six months 

 at ordinary temperature, a transparent silicious layer was ob- 

 tained, which, after heating to expel hygrometric water, took 

 the milky colour and the hardness of opal. It becomes trans- 

 lucid again in water. — On the cost of establishment of lightning- 

 conductors, by M. Melsens. He proves that his system of 

 numerous free conductors and multiple earth-connections is 

 generally less expensive than the construction of the ordinary 

 lightning-conductors. — On a disorder, not hitherto described, of 

 wines of the south of France called vins tournh, by M. Gautier. 

 This appears after warm and rainy autumns. The wine becomes 

 troubled, its surface irisated ; the colouring matter passes from 

 red to violet-blue, and is precipitated, the supernatant 

 liquor being yellowish-brown, and having a baked odour and an 

 acidulated and slightly bitter taste. These changes are worked 

 by a parasite which appears in filamentous form in the deposit. — 

 On the production of the luminous sensation, by M. Charpentier. 

 Where we find less red substance in the retina, we observe a less 

 luminous sensibility, and wherever the red appears in excess this 

 sensibility is exaggerated. It is concluded that the luminous 

 sensibility, defined as the simple and original reaction of the 

 visual apparatus to all luminous excitations of w'hatever nature, 

 is in relation to the degree of photo-chemical action exercised on 

 the red of the retina by all the luminous rays.— On the 

 physiological properties of conine, by MM. Bochefontaine and 

 Tiriakian. Conine pure, or bromhydrate of conine, is not a 

 very formidable poison, and not to be compared with hydro- 

 cyanic acid (as has been supposed). 65 centigr. of pure conine 

 introduced under the skin of a dog weighing 7 kil. odd killed it 

 in a little over twelve hours ; 50 centigr. sufficed for a similar 

 dog when introduced into the stomach. The chlorhydrate 

 and bromhydrate are always more active than the pure conine. 

 M. Mourrut has separated from the conine furnished as 

 pure in shops a resinoid matter, which, like curare, paralyses 

 the motor nerves. — Rdle of auxiliary acids in etherification ; 

 thermal experiments, by M. Berthelot.— On some peculiarities 

 presented in the arrangement of fire-damp in pits and old works, 

 by M. Coquillion. 



CONTENTS pITe 



Modern Naval Architecture. By E. J. Reed, C.B., M.P., 



F.R.S „• 137 



Tropical Nature. By Prof. E. Perceval Wright 140 



Letters TO THE Editor: — ^ . t . 



Extinct and Recent Irish Mammals.— Prof. A. Leith Adams. . 141 

 Hints to Workers with the Microscope.— F. A. Bedwell . . . .141 



The Virial in Thermodynamics.— Prof. A. S. Herschel .... 142 



The Meteor of May 12.— J. Edmund Clark 142 



"Divideetlmpera."—E. W.White, F.Z.S., S.S.Z. A 142 



A Quadruple Rainbow.— Henry P. Dowling 142 



Classes for Women at University College.— Talfourd Ely ... 143 



Prof. Joseph Henry, LL.D ^43 



Major-General Sir Andrew Scott Waugh 14S 



The Harvey Tercentenary i45 



Our Astrono.mical Column : — 



The Transit of Mercury '47 



The Zodiacal Light and Sun-spot Frequency ••■•'„•• ^'•'^ 

 The International Geological Congress. By Prof. 1. S terry 



Hunt, Secretary of the International Committee 140 



A Kinematical Theorem. By A. B. Kempe 140 



Old Maps of Africa (With Mafis) •■■■•• u • A ■•' ^^"^ 



Cosmic Meteorology, II. By John Allan Broun, l<.K.b.. . . 151 



The Nutrition of Drosera Rotundifolia. By Francis Uarwin 153 

 Physical Science for Artists, V. By J. Norman Lockybr, 



F.R.S. (With Illustrations) '54 



The Microphone in Surgery ^57 



The ReijeLecture. ' By Prof. Clerk-Maxwell, F.R.S i59 



Societies and Academies • -^^ 



Errata. -In Prof. Lankester's review of Balfour's " Elasmobranch 

 Fishes " vol. xviii. p. 114, 2nd column, line 22 from top, for /^.;«^^^«^^/« 

 read homogenetij \^ Dr. Siemens' letter on the microphone p 129 1 

 1st columnf lines 25 and 28 from top, for '.corpuscular bodies read cor-^ 

 pnscular matter. 



