Janu.\ry 28, 19 1 5] 



NATURE 



609 



Kunth (5. guaranifictim, Hassler) from the sys- 

 tematic point of view. 5. Caldasii and S. etuberosum 

 have been reg^arded by Berthault as identical species. 

 The author points out their differences, and stat''s 

 that the only point they have in common is the fact 

 that they both occur m Chili. — F. Bompiani : The 

 geometry of Laplace's equation. — J. Cabannes : The 

 diffusion of light by air. A beam of light from a 

 quartz mercury lamp was examined at right angles 

 to the path of the beam, and measurements made 

 both optically and photographically of the intensitv 

 of the diffused light. No diffusion occurs when the 

 beam is in a vacuum, and Lord Rajieigh's diffusion 

 formula was quantitatively confirmed. — L. Gay : The 

 expansibility product. — CEchsner de Coninck : The 

 molecular weight of the oxybenzoic acids. The 

 method is based on the determination of the calcium 

 in the calcium oxybenzoates, these being obtainable 

 in a state of high purity. — J. Repelin : The prolonga- 

 tion towards the east of the Senonian synclinal of the 

 Plan d'Aups, Saint-Baume. — Jean Chautaud : The 

 origin of the petroliferous mounds of Texas and 

 Louisiana. Contribution to the stud}* of the origin 

 of petroleum. The hypotheses put forward to account 

 for the formation of these mounds are not in accord 

 with the geological structure of the region. These 

 hypotheses are criticised in detail, and it is shown 

 that the mounds have an origin which is independent 

 of orogenic or . eruptive actions. The processes of 

 formation suggested by the author are sedimentation 

 in an intermittent lagoon, followed by a hydrocarbon 

 decomposition of the organic debris, the transforma- 

 tion of the anhydrite into gypsum, with resulting 

 compression and the migration of the petroleum 

 under the influence of the pressure exerted on the 

 mother rocks. — X. Arabu : Studies on the Tertiary 

 formations of the basin of the Sea of Marmora. The 

 Vindobonian in Thrace. — .A. Boutaric : The polarisa- 

 tion and absorptive power of the atmosphere. Ob- 

 servations carried on during three years confirm the 

 views of K. .\ngstrom that the absorptive power of 

 the atmosphere should depend on the diffusion and 

 qpantity.of the absorptive gas present, mainly water 

 vapour. The main factor is shown to be the dif- 

 fusion. From observations of calorific intensity, 

 polarisation, and hygrometric state carried out at a 

 given station for some years, it is possible to predict 

 the calorific intensity at different times on a given 

 day from measurements of the polarisation and hygro- 

 metric state, or even from a simple polari metric 

 obser\-ation alone. — .\. Goris and Ch. Vischniac : Tor- 

 mentol, a principle extracted from Potentilla tor- 

 meniilla. The substance is crystalline, contains no 

 nitrogen, and has the composition CjjH^oOio. Its 

 constitution has not been completely worked out, but 

 it is an ether-alcohol. — F. Bordas : A new arrange- 

 ment for the disinfection of clothing. .\ description 

 of an apparatus, easily put together, capable of dis- 

 infecting with steam at a temperature of 105° to 108° 

 the clothes of five hundred men per hour.— Victor 

 Henri : The possibilitv of phosphorus being carried 

 into wounds produced by the projectiles of the German 

 artillerv (see p. 598).— \V. R. Thompson : An intra- 

 cuticular parasite of Hamemalis virgiuiatia. 



January 18.— M. Ed. Perrier in the chair. — 

 Maurice Hamy : The exact determination of the 

 collimation of non-reversible meridian telescopes. It 

 is shown that the usual method of adjustment with 

 two collimators may be affected by a systematic error 

 and the substitution of two plane parallel mirrors is 

 suggested, their diameter being at least equal to that 

 of the objective of the instrument. Such mirrors can 

 now be made with high precision, and a method of 

 adjusting them to exact parallelism is given.— M. 



NO. 2361, VOL. 94] 



Guichard : Surfaces such that the centres of the spheres 

 osculating the lines of curvature of a series, shall be 

 a paraboloid of revolution. — F. Gonessiat : Results of 

 the observations of two occultations of the Pleiades 

 by the Moon. Details of observations made at Algiers 

 on September 20 and December 11, 1914. — B. 

 Jekhowsky : Observatibns of Delevan's comet, 1913/, 

 made at the Observatory of Paris, with the equatorial 

 in the western tower ot 30-5 cm. aperture. Positions 

 are given for December 18, 24, 26, 28, and 29, both 

 of the comet and the comparison stars. On December 

 29 the comet appeared as a rounded nebulosity 

 40 seconds diameter with a nearly stellar nucleus of 

 65 magnitude. — G. A. Miller : Sylow's theorem. — 

 Foveau de Courmelles : Determination of the position 

 of projectiles in the human body by radioscopy. Two 

 methods based on the use of a fluorescent screen are 

 described. — ^J. Bougault and Mile. R. Hemmerle : The 

 tautomerism of phenylpyruvic acid. In a previous 

 communication J. Bougault suggested that phenyl- 

 pyruvic acid might exist in two tautomeric forms, 

 enolic and ketonic. Further proofs of this isomerism 

 are now given, based on the differences in reactivity 

 of the acid and its alkali salts towards acetic acid, 

 potassium permanganate, and semicarbazide. The free 

 acid has the enolic form, C,H,.CH : C(OH).CO,H,, 

 Xhe neutral salts being ketonic, CsHj.CHo.CO.COjM. 

 The conditions for passing from the one form to the 

 other have been studied.— Ch. J. Gravier : A pheno- 

 menon of multiplication by longitudinal scission in a 

 Madrepore, Schizocyathus fissilis. — Alfred Angot : 

 Value of the magnetic elements at the Val-Joyeux 

 Observatory to January i, 19 15. — Alfred Angot : The 

 earthquake of January 13, 1915. From the records of 

 the seismograph at Pare Saint-Maur; the position of 

 the epicentre was easily fixed at about 1300 kilometres 

 S.E., that is, in Italy. The displacement was much 

 less than that caused by the earthquake in Russian 

 Turkestan on January 3, 1911. — ^J. Danysz : The treat- 

 ment of wounds by solutions of nitrate of silver of 

 strengths i in 200,000 to i in 500,000. A demonstra- 

 tion of the advantages of using certain antiseptic 

 substances, especiallv silver nitrate, in very dilute 

 solution. 



BOOKS RECEIVED. 



Smithsonian Miscellaneous Collections. Vol. Ixii., 

 No. 6. Smithsonian Physical Tables. Prepared by 

 F. E. Fowle. Sixth revised edition. Pp. xx.xvi + 355. 

 (Washington : Smithsonian Institution.) 



Egvptian Government. Almanac for the Vear 1915. 

 Pp. viii + 250. (Cairo: Government Press.) P.T.5. 



The South African Institute for Medical Research. 

 Anthropological Notes on Bantu Natives from Portu- 

 guese East Africa. By G. D. Maynard and G. .\. 

 Turner. Pp. 35. (Johannesburg : South African In- 

 stitute for Medical Research.) 2s. 6d. 



The Case-Hardening of Steel. By H. Brearley. 

 Pp. XV+ 169. (London : Iliffe and Sons, Ltd.) ys. bd. 



African .\dventure Stories. By J. .\. Loring. Pp. 

 X + 301. (London : G. Allen and L'nwin, Ltd.) tts. 

 net. 



The History of Melanesian Societ)-. By \V. H. R. 

 Rivers. Vol. i. Pp. xii + 400. \'ol. ii. Pp. ()io. 

 (Cambridge University Press.) 2 vols. 365. net. 



Macmillan's Geographical Exercise Books, iii. The 

 British Isles, with Questions by B. C. Wallis. 

 Pp. 48. (London : Macmillan and Co., Ltd.) 6</. 



A Shilling Arithmetic. By \V. M. Baker and A. A. 

 Bourne. Pp. xiv+192. (London: G. Bell and Sons, 

 Ltd.) IS. 



