2ih 



NATURE 



[May i6, 1918 



period- of • incubation obeys- very exactly the law of 

 Gauss, the average duration being thirty-four days. — 

 L. Roy : The problem of reflection and refraction by 

 plane periodic waves. — F. B. de Lenaizan : The resist- 

 ance of the electric spark. — P. L. Mercanton : The 

 magnetic state of some prehistoric pottery. The 

 articles examined were taken ftom Swiss lakes 

 (Bienne, Zurich, Pfiiffiken), and from magnetic ob- 

 servations on nine pieces the conclusion is drawn that 

 at the time and place of manufacture the terrestrial 

 magnetic inclination was nearly zero. — P. Chevenard : 

 The determination of the velocities of cooling neces- 

 sary for the realisation of tempering in carbon steels. 

 The results for a series of steels with carbon graded 

 from 02 per cent, to o-8 per cent, are given in the 

 form of curves.— C. Matignon and F. Meyer : The 

 double sulphate of soda and ammonia. Thermo- 

 chemical and solubility data. — P. de Sousa : The epiro- 

 genic movements during the Quaternary at Algarve, 

 Portugal. — E. Hernandez-Pacheco : The Archaeocyatidae 

 of the Sierra de Cordoba (Spain). — A. Gudbhard : 

 Remarks on the sedimentary crust. — E. Sailiard : 

 The balance of some constituent principles of the 

 sugar-beet during the manufacture of sugar. The 

 various products arising during the extraction of sugar 

 from the sugar-beet have been analysed, and the data 

 used to construct balance-sheets for the dry material, 

 nitrogen, potash, soda, and phosphoric acid. The 

 three last-named substances can be practically all 

 recovered and returned to the soil, but about one- 

 half of the nitrogen cannot be utilised. — L. Devillers : 

 The determination of the indigestible residue in vitro 

 produced by pancreatin acting upon wheat or the 

 products of milling and baking. Figures are given for 

 fourteen samples of wheat, flour, and bread. — 

 F. Guitel : The first stages of the development of the 

 adhesive apparatus of Lepadogaster. — ^A. Nanta : The 

 initial alterations of the liVer in great traumatisms. 



BOOKS RECEIVED, 



The Third and Fourth Generation : An Introduction 

 to Heredity. By E. R. Downing. Pp. xi + 164. 

 (Chicago : University of Chicago Press ; London : 

 Cambridge University Press.) i dollar net. 



Plant Products and Chemical Fertilizers. By S. H. 

 Collins. Pp. xvi + 236. (London: Baillifere, Tindall, 

 and Cox.) 75. 6d. net. 



The Alkali Industry. By J. R. Partington. 

 Pp. xvi + 304. (London: Bailliere, Tindall, and Cox.) 

 7^. 6d. net. 



University of Chicago. Publications of the Members 

 of the University, 1902-1916. Pp. x + 518. (Chicago: 

 University of Chicago Press ; London : Cambridge 

 University Press.) 



Bibliography of the Geology and Eruptive Pheno- 

 mena of the More Important Volcanoes of Southern 

 Italy. Compiled, with the assistance of Madame A. 

 Johnston-La vis, by Dr. H. J. Johnston-Lavis. Second 

 edition. Pp. xxiv + 374. (London: University of 

 London Press, Ltd.) 



Yorkshire Type Ammonites. Edited by S. S. Buck- 

 man. Part XV. (London : W. Wesley and Son.) 

 35. 3d. net. 



The Athenaeum Subject Index to Periodicals, 1916. 

 Science and Technology, including Hygiene and Sporf. 

 Pp. 162. (London : The Athenaeum^) 10s. net. 



A Handbook on Antiseptics. By Drs. H. D. Dakin 

 and E. K. Dunham. Pp. ix+129. (New York: The 

 Macmillan Co.; London: Macmillan and Co., Ltd.) 

 75. net. 



The Botany of Iceland. Edited by Drs. L. K. 

 Rosenvinge and E. Warming. Part i'l. Pp. 347 to 

 675. (Copenhagen: J. Frimodt; London: J. Wheldon 

 and Co.) 55. 6d. net. 



NO. 2533, VOL. lOl] 



DIARY OF SOCIETIES, 



THURSDAY, May i6. 

 RovAL Society, at 4.30.— Note on Certain Coloured Interference Bands 

 and the Colours of Tempered Steel : A. Mallock. — General Factors in- 

 Mental Measurements : J. C. M. Garnett.— The Absorption of X-Rays in 

 Copper and Aluminium : C. M. Williams. — The Electrical Resolution and 

 Broadening of Helium Lines : Dr; T. R. Merton. 

 Royal Institution, at 3.— The Prosecution and Punishment of Animals : 



Sir J. G. Frazer. 

 Roval Society of Arts, at 4.30.— The Freedom of the Sea : John 



Leyland. • ■ 

 Institution of Mining and Mf.tallurgy, at 5.30. 



FRIDAY, May 17. 

 Royal Institution, at 5.30.— The Story of a Grass : Dr, A". B. Rendle. 



TUESDAY, 'M\\-2j. 

 Royal Institution, at 3.— A Master of OTethod— Pitt-Rivers : Prof. A. 

 Keith. 



THURSDAY, May 23. 

 Royal Institution, at 3.— The Abode of Snow; Its Appearance, Inhabi- 

 tants, and History : Sir Francis Younghusband. 

 Institution of Electrical Engineers, at 6.— Some Transient Pheno- 

 mena in Electrical Supply Systems : Prot. E. W. Marchant. 

 FRIDAY, May 24. 

 Royal Institution, at 5.30.— Internal Ballistics: Lt.-Col. A. G. Hadcock. 

 Linnean Society, at 3. — Anniversary Meeting. 



SATURDAY, May 25. 

 t 3. — Problems in Bird-Migration ; 



Prof. C. J. 



Royal Institution, 



Patten. 



TUESDAY, May 28. 

 Zoological Society, at 5.30.— A Case of Hermaphroditism in a Lizard, 



Lacerta viridii : Noel Taylor.— Fresh-water Fish as Food : C. Tate 



Regan. 



CONTENTS. PAGE 



Aerodynamics. By S. B 201 



Military Psychology 201 



Ozone as a Hygienic Agent. By Prof. F. G. Donnan, 



F.R.S 202 



Our Bookshelf . 202 



Letters to the Editor:— 



Cotton-growing Statistics. — Dr. W. Lawrence 



Balls ; The Writer of the Article 203 



The Duration of Resonance in the Internal Ear. 



(/^/V/4 Z)2a^;w//.)— Dr. W. Perrett 204 



Recovery of Speech through Excitement. — G. Arch- 



dall Reid . 204 



A Study in Conditions of Human Nurture. {Illus- 

 trated.) 20:; 



The Development of Technical Research. ByH. L. 206 



Conference of Universities 207 



Notes 208 



Our Astronomical Column : — 



Nova Monocerotis .212 



The Atomic Weight of " Nebulium " . 212 



Hyderabad Astrographic Catalogue 212 



The Co-ordination of Scientific Publication .... 213 



The Diurnal Variation of Terrestrial Magnetism . 213 



Galvanometric Records of Emotivity. (Illustrated.) 214 



Atmospheric Pollution. ByJ. B. C 214 



Lubricating Oils 214 



Statistical Methods Applied to Practical Problems. 215 



Methods of Gas Warfare 215 



Crystals obtained from Glass Furnaces 217 



The Carnegie Institution of Washington 217 



University and Educational Intelligence . . . 218 



Societies and Academies 219 



Books Received 220 



•Diary of Societies 220 



Editorial and Publishing Offices: 

 MACMILLAN AND CO., Ltd., 

 MARTIN'S STREET, LONDON, W.C.2. 



ST. 



Advertisements and business letters to be addressed to the 

 Publishers. 



Editorial Communications to the Editor. 

 Telegraphic Address : Phusis, London. 

 Telephone Number : Gerrard 8830. 



