June i8, 1896] 



NA rURE 



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compare A with C, «e have a del'miie parallelepipeil whose 

 edges remain unchanged in direction. — Mr. R. C. Mossman 

 gave the first part of a communication on the meteorolog)' of 

 Edinburgh, in which he dealt with the mean values of the 

 climatic elements for each day of the year, basing his inquiry on 

 over a million observations. The non-instrumental records 

 extended over 125 years, and the daily sunshine means over 

 30, the average of the nineteen classes of observation being 

 about So years. As regards pressure, the maximum was 

 from April 7 to July 3, and the minimum on November 26. 

 For temperature the maximum was an average of 59°'3 on 

 August S, while January 8 was the colilest, the mean temper- 

 ature being 36"'o. The curve of rainGill showed that the seven 

 days ending April iS were the wettest days in the year, thus 

 confirming the popular belief in ihi- Lammas floods. Mr. 

 Mossman described in detail the climatic features of each 

 month, and showed how these reacted on each other. An 

 interesting result was the recurrence <>f similar types of weather 

 at the same time each year. — Mr. Malcolm Laurie read a paper 

 on the nutrition of the embryo in scorpions. The variation in 

 the modes of development in different genera of scorpions is 

 very large. The primitive form seems to be a large egg with 

 nuich food yolk, and is found in Eus(orpius and the Biithidii. 

 This egg develops in the ovarian tube. In other Jicrz(l<c the 

 egg is yolkless, though appearing to be a considerable size 

 owing to the surrounding embryonic membranes. In the 

 Scorpionidit the egg is entirely without yolk, and develops in 

 a diverticulum of the ovarian tube. \'arious contrivances exist 

 for the better nourishment of the embryo during the later stages 

 of development. Nourishment, secreted by the cells of the 

 diverticulum and by a .solid cord of cells (appendix) in which it 

 terminates, is always taken in through the mouth, which is early 

 developed. In addition to this, in Ischniirtis, the chelicerce 

 grow into long root-like processes which lie among the cells of 

 the appendix, and seem to absorb nourishment from them. In 

 Hormtirtis a similar function is performed by the chelse, 

 while in the Scorpioiniii the chelicerie grasp a cord of cells 

 coming from the centre of the appendix, and masticate it. In 

 these la.st forms there are also present dorso-lateral out-growths 

 of the segments of the body, which appear to act as surfaces for 

 absorbing nourishment directly from the surrounding maternal 

 tissues. This arrangement is carried still further in OpisihopJi- 

 thalmus, where there are two long processes, one from the 

 prostomium, and the other from the back of the carapace, which 

 run out among the maternal tissues. 



Dublin. 

 Royal Irish Academy, June S. — Dr. J. Kells Ingram, 

 Vice-President, in the chair. — Mr. Charles J. joly read a paper 

 on quaternion invariants of linear vector functions and 

 quaternion determinants. This was a supplement to a paper 

 read before the Academy in December 1895, and published in 

 their Transactions (vol. xxx. part 18). From given linear 

 vector functions others are derived by repeated multiplication in 

 any order. The Hamiltonian and other quaternion invariants of 

 these new functions are expressed as the quotients of two deter- 

 minants with vector constituents. Their scalar parts having 

 been considered in the previous paper, their vector parts are now 

 reduced to the results of operation on the spin-vectors of the 

 given functions, and of one function of each of certain cyclical 

 groups of the derived function.s. Examples and interpretations 

 are also given of determinants with quaternion constituents in 

 the expansion of which the order of the rows is preserved. — 

 Mr. Henrj' Dixon read a paper on the osmotic pressures in the 

 cells of leaves. The method adopted for estimating the osmotic 

 pressures existing in the cells of leaves, consisted in enclosing a 

 branch bearing a number of leaves in a strong glass cylinder, 

 capable of resisting high gas pres.sures {f.g. 50-100 atmospheres). 

 The ends of this cylinder consist of sltiut bra.ss castings, drawn 

 together on the cylinder by means of bolts and nuts. The upper 

 end is furnished with suitable couplings for connection with an 

 air compression pump or an iron bottle containing liquid CO.,. 

 The lower end is perforated and admits of the branch, to be 

 experimented with, being sealed into it. The cut end of the 

 branch dips into a vessel containing a weighed amount of water, 

 which is placed below the glass cylinder. When the pressure in 

 the cylinder is raised, it is found, that at a certain pressure, the 

 leaves begin to collapse and lose their turgescence, and that 

 water is forced down from them into the vessel beneath. By a 

 series of experiments on each branch, a certain critical pressure 



NO. 1390, VOL. 54] 



is found which just balances tlie osmotic pressure of the cells, 

 but which neither causes their colIap.se nor permits of their 

 drawing up water from below. 



Paris. 

 Academy of Sciences, June 8.— M. A. Cornu in the 

 chair. — Theory of the flow cif water in conduits, by M. J. 

 Boussinesq. — On the effect produced by the ring in iron "in 

 dynamo-electric machines. Reply to the note of M. Potier, by 

 M. Marcel-Deprez. — Study of melted vanadium and its carbide, 

 by M. H. Moissan. Vanadium pentoxide, reduced by carbon 

 in the electric furnace, yields an ingot of metal which always 

 contains an appreciable amount of carbon. If the time of heat- 

 ing is as short as possible, a metal containing only 5 per cent. o. 

 carbon can be obtained ; by prolonging the time of heating the 

 percentage of carbon increased to i8'5 per cent., indicating the 

 formation of the carbide VC. The carbide is not attacked by 

 water at the ordinary temperature. Vanadium forms alloys with 

 iron, copper, and aluminium, but not with silver. — On a new 

 method of prepaiing alloys, by M. H. Moissan. Alloys of 

 refractory metals can be prepared by projecting a mixture of the 

 oxide with powdered aluminium into a bath of liquid aluminium. 

 The heat set free by the oxidation of the aluminium is suflicient 

 to carry on the reaction. Alloys of aluminium with nickel, 

 molybdenum, tungsten, uranium and titanium have been 

 obtained in this way. — On the nature of the chemical processes 

 involved in muscular action, by M. A, Chauveau. Summing 

 up the results of a series of experimental researches on the 

 relation between the energ)^ given out as muscular work and 

 the energy absorbed as food. — On the value as food of bread 

 made from screened flours, by M. A. Girard. Analyses of flours 

 of various qualities, from which the conclusion is drawn that the 

 ideas generally held concerning the inferior nutritive power of 

 fine white bread as compared with brown bread, are fallacious ; 

 both kinds of bread containing ])ractically identical amounts of 

 gluten and of phosphates. — On the theory of gases, a letter 

 from M. Boltzmann to M. Bertrand, continuing the discussion 

 concerning the validity of Maxwell's formula for the distribution 

 of the velocities of the molecules at a given instant. — Reply to 

 the preceding by M. Bertrand, by whom Maxwell's theorem is 

 held to be obviously inaccurate. — The influence of the tempera- 

 ture of the freezing mixture upon cryoscopic measurements, by 

 M. F. M. Raoult. Starting from simple considerations an 

 expression is obtained giving a correction for super-cooling in 

 cryoscopic measurements. This formula is identical with that 

 given by MM. Nernst and Abegg, but the practical application 

 of it given by the latter, is open to criticism. A very simple 

 and accurate method is given by M. Raoult, who shows that the 

 temperature of the bath is without practical effect upon the laws 

 previously published. In the few cases where the correction is 

 necessary, it is ea.sily measured and applied. — On difterential 

 equations of the first order, by M. P. Painleve. — On the regula- 

 tion of motors, by M. L. Lecornu. — Observations on the errors 

 due to variations of temperature in geodesic instruments, by 

 H. F. A. Aimo. A discus.sion of the effect of temperature upon 

 the size and shape of the air-bubble in levelling instruments. — 

 On the spectra of metalloids in fused salts, by M. A. de 

 Gramont. Measurements of the lines due to sulphur in metallic 

 sulphides. — Contributions to the study of ab.sorption by porous 

 bodies, by M. Lachaud. An experimental study of the amounts 

 of quinine, methyl-violet, salicylic acid, tannin, dextrine, and 

 gelatine remaining in solution after treatment with animal 

 black. — On the estimation of potassium, by M. Charles Fabre. 

 The platinochloride is reduced in warm aqueous solution by 

 magnesium powder, and the resulting chloride titrated with 

 standard silver solution. — On the heat of vaporisation of formic 

 acid, by Miss D. Marshall. By comparison with benzene as a 

 standard substance, the value for the latent heat of vaporisation 

 of formic acid was found to be I20'4, a number practically 

 identical with that (l20'9) calculated from M. Raoult's formula 

 containing the rate of variation of vapour pressure with tempera- 

 ture, the absolute boihng point, and the molecular lowering of 

 the vapour pressure as the experimental data. — Combinations of 

 antipyrin with oxybenzoic acids and their derivatives, by MM. 

 G. Patein and E. Dufau. — On lighting by acetylene, by ^L G. 

 Trouve. A description of the methods used for the practical 

 preparation of acetylene for lighting purposes from calcium 

 carbide. — On the composition of the red pigment of Amanita 

 miiscaria, by M. A. B. Griftiths. — On the larval metamorphoses 

 of the Phoronis sabaticri, b)' M. Louis Roule. — Description o. 

 a new genus of simple Ascidia, Gamaster Dakarenis, by M. A. 



