586 



NATURE 



[January 20, 19 16 



Canada. Department of Mines. Geolog^ical Survey. 

 Memoir 50 : Upper White River District, Yukon. 

 By D. D. Cairnes. Pp. iv+191. Memoir 60: 

 Arisaig — Antigonisli District, Nova Scotia. By M. Y. 

 Williams. Pp. vi+173. Memoir 81: The Oil and 

 Gas Fields of Ontario and Quebec. By W. Malcolm. 

 Pp. ii + 248. (Ottawa : Government Printing- Bureau.) 



Engineering Geology. By Profs. H. Ries and T. L. 

 Watson. Second edition. Pp. xxvii + 722. (New 

 York : J. Wiley and Sons, Inc. ; London : Chapman 

 and Hall, Ltd.) 175. net. 



Mathematical Tables for Class-room Use. By M. 

 Merriman. Pp. 67. (New York : J. Wiley and Sons, 

 Inc. ; London : Chapman and Hall, Ltd.) 2s. (^d. 

 net. 



Decorative Design. By J. C. Chase. Pp. vi + 73. 

 (New York : J. Wilev and Sons, Inc. ; London : Chap- 

 and Hall, Ltd.) 6s." 6d. net. 



A Plea for an Orderly Almanac By A. Philip. 

 Pp. 62. (Brechin : D. H. Edwards.) \s. net. 



Report on the Operations of the Department of 

 Agriculture, Madras Presidency, for the Official Year 

 1914-15. Pp. 56. (Madras : Government Press.) 



Meteorological Office. British Meteorological and 

 Magnetic Year Book, 1913. Part iv.. Section 2. 

 Hourly Values from Autographic Records : Geo- 

 physical Section, 1913. Pp. 97- (Edinburgh : 

 H.M.S.O. ; London : Meteorological Office.) 5s. 



Egyptian, Government. Almanac for the Year 1916. 

 Pp. viii + 248. (Cairo: Government Press.) 



Problems in the Calculus with Formulas and Sug- 

 gestions. By Dr. D. D. Leib. Pp. xi + 224. (Boston 

 and London : Ginn and Co.) 4s. 6d. 



The Apple : a Practical Treatise dealing with the 

 latest Modern Practices of Apple Culture. By A. E. 

 Wilkinson. Pp. xii + 492. (Boston and London : Ginn 

 and Co.) 85. *6c/. 



The Mechanism of Mendelian Heredity. Bv Prof. 

 T. H. Morgan, A. H. Sturtevant, H. J. MuUer, and 

 C. B. Bridges. Pp. xiii + 262. (London : Constable 

 and Co., Ltd.) 125. net. 



Aircraft in Warfare : the Dawn of the Fourth Arm. 

 By F. W. Lanchester. Pp. xviii + 222. (London : 

 Constable and Co., Ltd.) 12s. 6d. net. 



DIARY OF SOCIETIES. 



THURSDAY, January 20. 



Royal Institution, at 3.— The Utilisation of Energy rom Coal : The 

 Chemistry and Economics of Coal and its By-Products : Prof. W. A. 

 Bone. 



Linnean Society, at 5.— The Definition of " Right " and " Left" in rela- 

 tion to Coiled, Rolled, Revolving, and Similar Objects: a Problem in 

 Scientific Terminology : Miller Christy.— Some Aspects of the Baeshot 

 Sands Flora : H. W. Monckton. — Colour-photographs of MoUu'ca : B. H. 

 Woodward. 



Royal Geographical Society, at 5.— The Middle Tees and its Tribu- 

 taries: C. B. Fawcett. 



Institution of Electrical Engineers, at 8.— The Principles of Modern 

 Printing Telegraphy : H. H. Harrison. 



Institution of Mining and Metallurgy, at 5.30. — Chinese Mining 

 Legislation: W. F. Collins.— Taylor's Pulp Sampler: W. H. Trewartha- 

 Jame<. 



FRIDAY, January 21. 



Royal Institution, at 5.30.— Problems in Capillarity: Sir James Dewar. 

 Institution of Mechanical Engineers, at 6.— The Flow of Air through 

 Nozzles: Capt. T. B. Morley. 



MONDAY, January 24. 

 Royal Geographical Society, at 8.30.— Cyrenaica : Prof. J. W. Gregory. 



TUESDAY, January 25. 

 Royal Institution, at 3.— The Physiology of Anger and Fear: Prof. 



C. S. Sherrington. 

 Institution of Civil Engineers, at 5.30.— Discussion : The Electric 



Locomotive : F. W. Carter. 



IVEDNESDAY, January 26. 



Royal Society of Arts, at 4.30.— The Effect of the War on Cotton Grow- 

 ing in th« Briiish Empire : J. A. Hutton. 



THURSDAY, January 27, 



Royal Society, at \.t,o.— Probable Papers : The Theory of the Helmholtz 

 Resonator : Lord Rayleigh.— A Collision Predictor : Prof. J. loly.— 

 Discussion of Kew Magnetic Data, especially the Diurnal Irregularities 

 of Horizontal Force and Vertical Force, from ordinary days of the eleven 

 years 1890 to 1900: Dr. C. Chree. — A Portable Variometer for Magnetic 

 Surveying : G. W. W.alker.— The Single Line Spectrum of Magnesium 

 and other Metals and their Ionising Potentials : Prof. J. C. McLennan.— 

 The Microscopic Structure of Semipermeable Membranes, and the Part 

 Played by Surface Forces in Osmosis : F. Tinker. — The Reduction of 

 Metallic Oxides with Hydrogen afc High Pressures : E. Newberyand J. N. 

 Pring. — Discontinuous Fluid Motion Past a Curved Boundary: H. l.pvy. 



Royal Institution, at 3. — Fuel Economy from a National Standpoint- 

 Prof. W. A. Bone. 



FRIDAY, January 28. 

 Royal Institution, at 5.30.— The Science of Clothing and the Prevention 



of Trench P'eet : Dr. Leonard Hill. 

 Physical Society, at 5.— Guthrie Lecture: Some Problems of Living 



Matter : W. 13. Hardy. 



PAGE 

 • 559 



CONTENTS. 



Arc Light 



"Vigour" and "Instinct" 561 



Introductory Treatises on Mechanics 562 



Our Bookshelf 563 



Letters to the Editor:— 



Instruction in Science for Military Purposes. — 



Chas. R. Darling ..... 564 



A Relation between Atoniic Weights and Radio- 

 active Constants. {IFith Diagyarn.) — F. Gilbert 



Carruthers 565 



The Naming of Earthquake.?.— Dr. Charles Davison 566 



Origin of Greek Tragedy. {Illustrated.) 567 



The Metric System and Decimal Coinage. By 



G. H. B 568 



Notes 570 



Our Astronomical Column :— 



Comet 1915^ (Taylor) " . 575 



Comet i9i5^(MelIish) 575 



Mira Ceti 575 



Second Type Stars of Low Density 575 



The Distribution of Spectroscopic Binaries of Class M 575 



Report of the Nizatniah Observatory 575 



The Variable Nebula, N.G.C. 6729 575 



British Rainfall in 1915 576 



Science at Educational Conferences. II. By G. F. 



Daniell 576 



Modern Systems of Independent Lighting and 



Heating. III. {Illustrated.) 577 



The Bonaparte Fund for 1915 578 



The Principles of Crop Production. {Illustrated.) 



By Dr. E. J. Kussell 579 



University and Educational Intelligence 583 



Societies and Academies 5^4 



Books Received 5^5 



Diary of Societies 5^6 



Editorial and Publishing Offices: 



MACMILLAN & CO., Ltd., 



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



Advertisements and business letters to be addressed to the 

 Publishers 



Editorial Communications to the Editor. 

 Telegraphic Address : Phusis, London. 

 Telephone Number : Gerrard 8830. 



NO. 2412, VOL. 96] 



