March i i, 1909] 



NA TURE 



59 



e.g. if skin, led off by electrodes A and B applied to its 

 external surface, is warmed at B there is a current in 

 the galvanometer from A to B (" ingoing " current at B, 

 or B " negative " to A). If it is excited at B there is 

 current in the galvanometer from B to A (" outgoing " 

 current at B, or B " positive " to A). The internal surface 

 is ineffective. Both surfaces of scalded skin are in- 

 effective. Conclusion. — In muscle (and in nerve) where 

 the electrical efTect of local excitation is " negative," the 

 effect of moderate heat is " positive." In the skin where 

 the electrical effect of local excitation is " positive," the 

 effect of moderate heat is "negative." Excessive heat, 

 producing injury, gives a " negative " effect in muscle (and 

 nerve), a " positive " effect in the skin. Thus in all three 

 cases — muscle, nerve, and skin — the electrical effect of 

 moderate heat is of the opposite sign to that of excitation. 



Royal Microscopical Society, February 17. — Sir E. Ray 

 Lankester, K.C.B., F.R.S., president, in the chair. — The 

 " red snow " plant (Sphacrella nivalis) : Dr. G. S. West. 

 — A German-sjlver portable microscope made by Powell in 

 1850 : A. A. C. E. Merlin. — The measurement of very 

 minute microscopic objects : E. M. Nelson. — The trans- 

 formation of certain insects : F. Enock. — The fresh-water 

 Crustacea of Algeria : Mr. Gurney. 



Edinburgh. 

 Royal Society, February is.— Prnf. A. Gray, F.R.S., 

 vice-president, in the chair. — The electromotive force of 

 iodine concentration cells with one electrode saturated with 

 iodine : Principal A. P. Laurie. The paper dealt with 

 the question as to what was the distribution between 

 iodine ions and I, ions in saturated solutions of iodine 

 and potassium iodide, the strength of the latter being in- 

 creased up to normal. This was determined by measuring 

 the electromotive force of iodine concentration cells with 

 a known and very small quantity of iodine round one 

 electrode and a saturated solution of iodine round the 

 other, the potassium iodide being of the same strength in 

 both ca.ses. With the view of correcting the error due to 

 contact electromotive force between KI, and KI, an inter- 

 mediate solution of ten normal ammonium nitrate was 

 introduced. The results show that up to a strength of 

 normal potassium iodide there are no higher polyiodides 

 formed beyond KI,, the increasing solubility of iodine 

 being due to an alteration in the ratio of the dissociation of 

 I, into 1, and I. — The magnetic properties of certain copper 

 alloys : A. D. Ross and R. C. Gray. The paper was an 

 investigation of the effects on magnetic quality of anneal- 

 ing, quenching, baking, and liquid-air tests on manganese- 

 aluminium bronzes, in which the relative proportion of 

 manganese and aluminium was constant, while the content 

 of copper varied. Comparison was rhade with similar 

 effects in manganese, manganese bronze, manganese steel, 

 aluminium bronzes, and very pure copper. It was shown 

 that the effects obtained in Heuslcr's alloy present a sug- 

 gestive similarity to those in free copper.— Some low- 

 temperature experiments in magnetism : J. G. Gray and 

 Hugh Higrsins. According to Dewar and Fleming, a 

 specimen of steel when magnetised to saturation at room 

 temperature, and then cooled and warmed alternatelv 

 between —190° C. and 5° C, arrived at a reversible con- 

 dition in which its magnetic moment at — 190° was 

 greater than its magnetic moment at 5°. In the present 

 paper the specimen was magnetised at - iqo° and subiected 

 thereafter to the same treatment. The reversible condition 

 was arrived at after the first warming, and the percentage 

 increase then brought about by cooling was much greater 

 than that which held for the specimen when magnetised 

 at the room temperature. — Lagrange's equations of motion 

 and elementary solutions of gyrostatic problems : Prof. 

 A. Gray. The first part of the paper was a new dis- 

 cussion of the difficulties in applying Lagrange's equations 

 to what are known as non-holonornic systems. The 

 modified form of the equations which can he applied was 

 given. The elementary solutions depended upon the 

 generalisation of a theorem the fundamental nature of 

 which could be indicated bv the rule that the norma! 

 force on a particle moving in a circle was equal to the 

 momentum multiplied by the angular speed of the radius 

 vpi-for. 



NO. 2054, VOL. So] 



Paris. 

 Academy of Sciences, March l. — M. Eniile Picard in 

 the chair. — The supposed effect of crystallisation for 

 modifying the properties of the solution of a body result- 

 ing from the direct union of two solutions : D. Gernez. 

 The author has repeated an old experiment, according to 

 which a solution of the double tartrate of sodium and 

 ammonium, or of sodium and potassium, possesses a 

 different rotatory power according as the substance has 

 been crystallised out or not. This result is not confirmed ; 

 the rotatory power of the mixed tartrates is not affected 

 by crystallisation, followed by subsequent solution. — A 

 physico-chemical method of sterilising in the cold and at 

 a distance : A. Bilion-Daguerre. The ultra-violet rays 

 from an arc lamp kill Stapliylococcus pyogenes aureus in 

 five or six seconds. — The monogenic function of a hyper- 

 complex variable in a commutative group : Lton Autonne. 

 — The hypothesis of positive electrons. Reply to the note 

 of A. Dufour : Jean Becquerel. The experiment described 

 by Dufour is not a repetition of the one given by the 

 author. While not supposing that the hypothesis of positive 

 electrons is the only one capable of explaining the observed 

 facts, it is worthy of consideration, since it coordinates and 

 explains a number of magneto-optic phenomena.-r-Mole- 

 cular volumes, densities, and atomic weights : A. Leduc. 

 From the formula given in a previous paper the densities 

 (oxvgen taken as unity) of twenty gases are calculated, 

 and the calculated numbers compared with the experi- 

 mental figures, The atomic weights deduced from these 

 figures (0 = i6) are: — H = i-oo75, N= 14005, C = i2-004, 

 01 = 35.463, and 8 = 32.072. — Equilibria between the liquid 

 and solid phases in the mixture NaCl+H,0. The fusion 

 of snow : Camille Matigrnon. The complete curve for 

 the lowering of the melting point by the addition of 

 NaCI is given. The eutectic mixture contains 30-7 per 

 cent, of salt, and solidifies at — 2i°-3. — The determination 

 of some physical constants of the peptones : L. Lematte 

 and A. Saves. The peptones used contained i6-S per 

 cent, of nitrogen and 0-756 per cent, of chlorine as HCl. 

 Solutions of concentrations between 09 per cent, and 

 10 per cent, of peptones were examined for freezing point, 

 density, and refractive index, and the results given in a 

 fable.— The action of gaseous hydrochloric acid on amor- 

 phous silicon : A. Besson and L. Fournier. In this 

 reaction the .authors have isolated two new products, 

 SiH,Cl (boiling point about -10°) and SiHXl (boiling 

 point about + 12°). — The ammoniacal iridium sulphates : 

 Marcel Delepine. — The action of carbon monoxide upon 

 chromium, nickel, manganese, their oxides and alloys : 

 Georges Charpy. At 1000° C. nickel is practically with- 

 out action on carbon monoxide ; manganese gives a mix- 

 ture of MnO and carbon, and chromium resembles 

 manganese, but the action is slower. — Researches on the 

 occluded gases contained in some common metals : B. 

 Deiachanal. The metals examined were aluminium, 

 magnesium, zinc, tin, spongy platinum, platinum foil, and 

 platinum-iridium. Analyses of the gases evolved are given. 

 — The condensation of the mcsoxalic esters with aromatic 

 hydrocarbons : A. Guyot and G. Esteva. The condensa- 

 tion of mesoxalic esters with benzene and its derivatives 

 under the action of sulphuric acid takes place in two 

 stages, an aryl-tartronic ester, X.C(OH).(CO,R),, being 

 first formed, and then a diaryl-malonic ester, X;.C(CO,R)„. 

 Numerous preparations are described showing the gener- 

 ality of the method. — Elaterine and some of its derivatives : 

 A. Berg- — The action of semicarbazide on chlorinated 

 aldehydes : .Andr6 Kling:. — New very sensitive reactions 

 for the detection and identification of glycerol : Georges 

 Denizes. The glycerol is oxidised by bromine water to 

 dioxyacetone, and application made of the various colour 

 tests described in a previous note. — The experimental pro- 

 duction of white and black tubercles, starting with seeds 

 of pink radish : Marin Moiliard. — The antagonism of 

 sodium and calcium citrates in the working of the heart 

 and its moderating nerve apparatus : H. Busquet and 

 V. Pachon. — The course of the oxidation and hydrolysis 

 of starch and its constituents under the action of hydrosen 

 peroxide : Mme. Z. Gatin-Gruzewski. There are distinct 

 differences between the modes of transformation of 

 amylose and amylopectin by diastases and by hydrogen 



