320 



NATURE 



[June 19, 1919 



haemoglobins, chlorophyll, and neodymium chloride. — 

 A. Colson : Reduction of cryoscopy to the general laws 

 of solubility. — A. Noyes : The counter e.m.f. of 

 polarisation in sulphuric acid. The counter e.m.f. 

 of a solution of sulphuric acid at first diminishes with 

 the temperature, proportionally to the reciprocal of 

 the absolute temperature. From 60° to 120° C. the 

 fall is more rapid, and above 120° it scarcely varies 

 at all. The change may be attributed to a difference 

 in the mode of ionisation. — G. Langlois : A new- 

 synthesis of benzylidene-acetone. Cinnamene is con- 

 densed with acetyl chloride in presence of diethyl- 

 aniline. The product was characterised as benzylidene- 

 acetone by its oxidation products, formation of 

 dibromide and semicarbazone, and by elementary 

 analysis. — J. Guyot and L. J. Simon: The action of 

 heat on the methylsulphates of the alkalis and alka- 

 line earths. At 22o°-28o° C. sodium and potassium 

 methylsulphates give methyl ether and a pyro- 

 sulphate, some methylsulphate being formed as a by- 

 product. With barium and calcium methylsulphates 

 methyl sulphate is the main product of the reaction, 

 with minimal proportions of methyl ether. — P. 

 Pelseneer : Production of hybrids in molluscs. — L. 

 Roule : The first phases of embryonic development in 

 Palemon serratus. Criticism of a recent communica- 

 tion to the Comptes rendus by M. E. SoUaud on the 

 development of Leander-Palemon squilla.- — C. Vaney 

 and A. AUemand-Martin : The action of Hippospongia 

 equina of the coasts of Tunis on the Posidonia.^ — H. 

 Contiere : The morphology of the limb of the Crus- 

 tacea.— E. Fernandez- Galiano : The conjunctive tissue 

 of the heart of the snail. — C. Gessard : An achromo- 

 genic variety of the pyocyanic bacillus.. This new 

 type gives pyocyanine on glycerine gelose-peptone, but 

 gives no pigment when cultivated in aqueous peptone. 

 M. Menard and C. Delval : The action of the X-rays 

 on fibro-myomas of the uterus in woman.- — A. Robin : 

 The hydration, soluble residue, and insoluble residue 

 in cancer of the liver. A new theory on the genesis 

 of cancer. . 



BOOKS RECEIVED. 



An Introduction to the Study of Science. By \V. P. 

 Smith and E. G. Jewett. Pp. xi + 620. (New York: 

 The Macmillan Co.; London: Macmillan and Co., 

 Ltd.) 7s. 6d. net. 



The Foundations of Geography in the Twentieth 

 Century. By F. Schrader. (Herbertson Memorial 

 Lecture, 1919.) Pp. 26. (Oxford : At the Clarendon 

 Press.) 25. 6d. net. 



The Analysis of Minerals and Ores of the Rarer 

 Elements. By Di. W. R. Schoeller and A. R. Powell. 

 Pp. x + 239. (London : C. Griffin and Co., Ltd.) 

 i6s. net. 



A Handbook of Medical Jurisprudence and Toxico- 

 logy. By Dr. A. Brend. Pp. xiii + 317. (London : 

 C. Griffin and Co., Ltd.) 105. 6d. net. 



An Arithmetic for Preparatory Schools, with 

 Answers. Bv T. Dennis. Second edition. Pp. xiv+ 

 376. (London : G. Bell and Sons, Ltd.) 45. 6d. 



Differential Calculus for Colleges and Secondary 

 "Schools. By Dr. C. Davison. Pp. viii-|-3og. 

 (London : G. Bell and Sons, Ltd.) 6s. 



DIARY OF SOCIETIES. 



THURSDAY, June 19. 

 Institution of Mining Enginef.ks, at 11.— Lt.-Col. D. Dale Logan : 

 (n) The Difficulties and Dangers of Mine-rescue Work on the Western 

 Front, and Mining Operations carried out by Men wearing Rescue- 

 apparatus ; (3) Accidents due to Structural Defects of Apparatus or 

 Injury to Apparatus, and the Future of the Proto Apparatus.— M. W. 

 Blyth and L. T. O'Shea : The Kxamination of Coal in Relation 

 to Coal-washing.— Prof. ¥. W. Hardwick : Replv to the Discussion 

 on his Paper on the Training of Students in Coal-mining, with Special 



Reference to the Scheme of the Engineering Training Organisation. — W. 

 Maurice : The Education of Colliery Managers for Administrative and 

 Social Responsibilities. 



RovAL SociBTY, at 4.30.— Bakerian Lecture. Hon. R. J. Strutt : A Study 

 of the Lii e Spectrum of Sodium as Excited by Huorescence. 



LiNNEAN Society, ai 5-— T. A. Dyrnes : Notes on the Life-history of the 

 Yellow Flag. Iris pseudaconts, Linn., with Special Reference to the 

 Seeds and Seedlings during their First Year.— Dr. G. H. Rodman : Egg- 

 ca'e of a Spider from the South of Vrnnce—Cyriarachnt tul crculifera. — 

 S. L. Moore : A Contribution to the Flora of Australia. — A. W. Waters : 

 Observations on Certain Species of Bryo/oa, chiefly belonging to the 

 SelenariadsE, Conescharellinida;, etc. — Dr. E. Penard : Studies on some 

 Flagellata. — I'r. \V. M. Tattersall : Report on the Stomatopoda and 

 Macrurous Decapoda Collected by Mr. Cyril Crossland in the Sudanese 

 Red Sea. 



Institution of Mining and Metallurgy, at 5.30. — W. H. Goodchild : 

 The Genesis of Igneous Ore Deposits. 



Chemical Society, at 8. 



WEDNESDAY. June 25. 



Geological Society, at 5.30.— A. E. Kitson : Outlines of the Geology of 

 Southern Nigeria (British West Africa), with Esnecial Reference to the 

 Tertiary Deposits.— Prof. J. B. Harrison and C. B. W. Anderson : Notes 

 on the Extraneous Minerals in the Coral-Limestones of Barbados. 



THURSDA Y, June 26. J 



Royal Society, at ^.-^o.—trohable Pape?-s : Dr. A. E. H. Tutton : Mono- v 

 clinic Double Selenates of the Cobalt Group. — Bertha Ayrton : A New » 

 Method of Driving oft" Poisonous Gases. Dr. F. W. Aston : Experiments 

 with Perforated Klectrodes on the Nature of the Discharge in Gases at 

 Low Pressure. — Mary Seegar and Prof Karl Pearson : De Saint-Venant 

 .Solution for the Flexure of Cantilevers of Cross-section in the Form of 

 Complete and Curtate Circular Sectors ; and on the Influence of the 

 Manner of Fixing the Built-in End of the Cantilever on its Deflection. — 

 Dr. H. Jeffreys : The Relation between Wind and the Distribution of 

 Pressure. 



FRIDAY, June 27. 



Physical Society, at 5. — Prof C. L. Fortescue : The Current- Voltage 



Characteri'tics of" High-Voitage Thermionic Rectifiers. — Prof. Ernest 



Wilson : The Measurement of Small Susceptibilities by a Portable 



Instrument. 



CONTENTS. PAGE 



Text-books of Botany 3or 



Optics and Mechanics. By Dr. H. S. Allen .... 302 



Secret or Mystery .' 303 



Our Bookshelf 303. 



Letters to the Editor:— 



Wireless Telephony.— A. A. Campbell Swinton, 



F.R.S ' . 304 



Camouflage of Ships of War.— Lt.-Comdr. Norman 



Wilkinson 304 



Question Relating to Prime Numbers. ( With Dia- 

 gram.)— A. Mallock, F.R.S 305 



The Atlantic Flight „ 306 



British Petroleum 306 



Father Walter Sidgreaves, S.J 307 



Notes 308 



Our Astronomical Column : — 



The Solar Eclipse of May 29 311 



The Astrographic Catalogue 312 



The British Science Guild 312 



Imperial Education Conference 313 



The Royal Observatory, Greenwich 313 



The South-Eastern Union of Scientific Societies . 314 



The Texture of Sands. (Illustrated.). By P. G. H. B. 315 



The American Philosoptiical Society 317 



University and Educational Intelligence 317 



Societies and Academies 319 



Books Received ... 320 



Diary of Societies 320 



Editorial and Publishing Offices: 

 MACMILLAN AND CO., Ltd., 

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



Advertisements and hiisiness letters to be addressed to the 

 Publishers, 



Editorial Communications to the Editor. 

 Telegraphic Address: Phusis, London. 

 Tele{)hone Number : Gerrard 8830. 



NO. 2590, VOL. 103] 



