March 20, 1913] 



NATURE 



— Et. Delassus : The equilibrium and small movements 

 of systems submitted to linkages of any order what- 

 ever. — Andre Blondel : The internal power and syn- 

 chronising couple of synchronous alternators working 

 on a network at constant potential or in parallel. — 

 Casimir Cepede : A new method of mounting micro- 

 scopic preparations permitting the study of both faces 

 of the section .under the strongest magnifications, and 

 •doing away with the necessity of special methods of 

 packing. A hole is bored in the glass slide in such 

 a manner thr the object can be imbedded between 

 two cover glasses. This allows either side to be 

 examined, and the slides can be packed vertically in 

 contact with each other without danger of damaging 

 the section. — Pierre Goby : A new application of the 

 X-rays : microradiography. The apparatus described 

 and figured gives an enlarged radiogram of small 

 objects. Illustrations are given of radiograms from 

 twelve to seventeen times the diameter of the original 

 objects. — G. Reboul : Capillary phenomena in gases. 

 Extension of the Laplace formula to solid-gas con- 

 tact. — Marcel Boll : The energy absorbed and mass 

 formed in a photochemical reaction. A study of the 

 conductivity of a very dilute solution of chloroplatinic 

 acid under the influence of a monochromatic radiation. 

 — Andre Kling and D. Florentin : The action of low 

 temperatures on explosives. The handling and open- 

 ing of explosive bombs has frequently to be under- 

 taken in the Paris Municipal Laboratory, and experi- 

 ments have been made to see if the force and velocity 

 of detonation of various explosives can be reduced by 

 cooling to the temperature of liquid nitrogen. It has 

 been found that the sensibility of some explosives and 

 detonators is reduced by cooling, but when explosion 

 takes place the force of the explosion is not affected by 

 the low temperature. — Victor Henri and Marc Landau : 

 Study of the absorption of the ultra-violet rays by 

 acetylene. Tables are given showing the positions of 

 the bands produced by the gas and by its solutions. — 

 Witold Broniewski : The critical points of iron. Heat- 

 ing curves are given for electrolytic iron and also the 

 results of measurements of the thermo-electric power, 

 electrical resistance, expansion, and thermal points. — 

 L. Guillet and A. Portevin : Some properties of a com- 

 mercial electrolytic iron. In this metal no carbon, 

 manganese, silicon, or sulphur could be detected. It 

 contained phosphorus 0025 per cent., and arsenic o-on 

 per cent. Determinations were made of its critical 

 points, and two microphotographs are reproduced. — 

 H. Pelabon : Study of the system antimonv sulphide, 

 lead sulphide. Definite compounds were shown bv 

 the existence of transition points and confirmed 

 microscopically. — Daniel Berthelot and Henrv Gaude- 

 chon : A levulose actinometer for ultra-violet light. 

 The influence of the concentration on the velocity of 

 the photochemical reaction. In weak solutions the 

 absorption is slight and is proportional to the concen- 

 tration ; in concentrated solutions the absorption is 

 total, and does not increase with the concentration. — 

 MM. Lespieau and Bresch : The action of a-/3-dichlor- 

 ethvl ether on mixed magnesium derivatives. — Pierre 

 Jolibois : Methyl-magnesium iodide. By the action of 

 heat on methvl-magnesium iodide a substance is ob- 

 tained of the composition MgL,Mg,C. This is 

 attacked bv water, nearly pure methane being evolved. 

 — Andre Meyer: "Halochromy" in the derivaties of 

 phenylisoxazolone and in its indogenides. — Albert 

 Michel-Levy : The eruptive rocks of the Lvonnais. — 

 M. Maze : The relation which exists between the water 

 evaporated and the weight of plant material elaborated 

 by maize. — Eug. Rousseaux and Maurice Sirot : Soluble 

 nitrogenous material as a factor in valuintr flour. In 

 a good flour the ratio between the total nitrogen and 

 the soluble nitrogen should not fall below a certain 



figure. A low ratio corresponds with bad bread- 

 making properties. — A. Demolon : Researches on the 

 fertilising action of sulphur. The fertilising action of 

 sulphur may be attributed to its action on the micro- 

 organisms of the soil and also to its progressive 

 oxidation to sulphuric acid. — L. C. Soula : the activity 

 of the nervous centres and nitrogen catabolism of the 

 nerve substance. — Raphael Dubois : The nature and 

 development of the light organ of Lampyris noctiluca. 

 — Gabriel Bertrand and H. Agulhon : The presence of 

 boron in the animal kingdom. The authors conclude 

 that boron exists normally in very small proportions 

 in all animals. The amount is greatest in animals of 

 madine origin. — Henri Stassano : Contribution to the 

 knowledge of the plasma of propeptone. — H. Maurice : 

 The results given by captive balloons north of the 

 polar circle. Temperatures are given on the ground 

 and at varying heights up to 20,000 metres. — E. A. 

 Martel : Studv of the temperatures of subterranean 

 waters. 



BOOKS RECEIVED. 



Household Bacteriology for Students in Domestic- 

 Science. By E. D. Buchanan and Prof. R. E. 

 Buchanan. Pp. xv + 536. (London : Macmillan and 

 Co., Ltd.) 10s. net. 



Bucher der Naturwissenschaft. Band 15, Vom 

 Keim zum Leben. By Prof. K. Lampert. Pp. 198 + 

 xii plates. (Leipzig : P. Reclam, jun.) 1 mark. . 



Government of India. Department of Revenue and 

 Agriculture. Agricultural Statistics of India for the 

 Years 1906-7 to 1910-11, in 2 vols. Vol. ii., Native 

 States. Pp. 123. (Calcutta : Superintendent Govern- 

 ment Printing, India.) is. 6d. 



Garden Work : a Practical Manual of School 

 Gardening. By W. Good. Pp. xvi + 399 + plates. 

 (London : Blackie and Son, Ltd.) 3s. 6d. net. 



Die Methoden der exakten, quantitativen Bestimm- 

 ung der Alkaloide. By Prof. A. R. von Korczynski. 

 Pp. iv + 82. (Berlin: Gebriider Borntraeger.) 3.50 

 marks. 



Osmotic Pressure. By Prof. A. Findlay. Pp. vi + 

 84. (London : Longmans and Co.) 2s. 6d. net. 



Report of the Librarian of Congress and Report 

 of the Superintendent of the Library Building and 

 Grounds for the Fiscal Year Ending June 30,1912. 

 Pp. 235. (Washington : Government Printing 

 Office.) 



The Mosquitoes of North and Central America and 

 the West Indies. By L. O. Howard, H. G. Dyar, 

 and F. Knab. Vol. i., A General Consideration of 

 Mosquitoes, their Habits, and their Relations to the 

 Human Species. Pp. vii + 520. Vol. ii., Plates. Pp. 

 x+150 plates. (Washington: Carnegie Institution.) 



Carnegie Institution of Washington. Year Book. 

 No. 11, 1912. Pp. xvi + 294. (Washington: Carnegie 

 Institution.) 



The Classics of International Law. Edited by J. B. 

 Scott. De Jure Belli ac Pacis Libri Tres, in quibus 

 Ius Naturae and Gentium, item Juris Publici prcecipua 

 explicantur. Bv H. Grotius. Vol i., Reproduction of 

 the Edition of' 1646. Pp. 618. (Washington : Car- 

 nesfie Institution.) 



Researches of the Department of Terrestrial Mag- 

 netism. Land Magnetic Observations, 1905-1910. 

 By L. A. Bauer. Pp. iv+185. (Washington: Car- 

 negie Institution.) 



The Vulgate Version of the Arthurian Romances. 

 Edited from Manuscripts in the British Museum by 

 H. O. Sommer. Vol. vi. Pp. 391. (Washington : 

 Carnegie Institution.) 



The Nummulosphere : an Account of the Organic 

 Origin of so-called Igneous Rocks and of Abyssal 



NO. 2264, VOL. 91] 



