48o 



NATURE 



[February 14, 19 18 



Microscopical Examination of Steel. By Prof. W. 

 Fav. Pp. iv+ 18 + illustrations. (New York: J. Wiley 

 and Sons, Inc. ; London : Chapman and Hall, Ltd.) 

 6s. net. 



A Course in Food Analysis. By Dr. A. L. Winton. 

 Pp. ix + 252. (New York: J. Wiley and Sons, Inc.; 

 London : Chapman and Hall, Ltd.) ys. net. 



Irrigation Works Constructed by the U.S. Govern- 

 ment. By A. P. Davis. Pp. xvi + 413. (New York: 

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

 Ltd.) 216'. net. 



Engineering for Masonry Dams. By W. P. Creager. 

 Pp. xi + 237. (New York: J. Wiley and Sons, Inc.; 

 London: Chapman and Hall, Ltd.) \is, 6d. net. 



French Forests and Forestry, Tunisia, Algeria, Cor- 

 sica. With a translation of the Algerian Code of 1903. 

 By S. S. Woolsey, jun. Pp. xv + 238. (New York: 

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

 Ltd.) IIS. 6d. net. 



Lecture Notes on Light. By J. R. Eccles. Pp. vi + 

 215. (New York: J. Wiley and Sons, Inc.; London : 

 Chapman and Hall, Ltd.) 125. 6d. net. 



The British Journal Photographic Aljnanac and 

 Photographer's Daily Companion, iqi8. . Edited by 

 G. E. Brown. Pp. 660. (London : H. Greenwood and 

 Co., Ltd.) Js. 6d. net. 



A Laboratory Outline of College Chemistry. By Prof. 

 A. Smith. Pp. V + 206. (London : G. Bell and Sons, 

 Ltd.) 3s. net. 



Experimental Inorganic Chemistry. By Prof. A. 

 Smith. Sixth edition. Pp. vii+171. (London: G. 

 Bell and Sons, Ltd.) 3s. 6d. net. 



Introduction to Inorganic Chemistry. By Prof. A. 

 Smith. Third edition. Pp. xiv + 925. (London: G. 

 Bell and Sons, Ltd.) 85. 6d. net. 



Liquid Fuels for Internal Combustion Engines. Bv 

 H. Moore. Pp. XV4-200. (London : Crosby Lock- 

 wood and Son.) 125. 6d. net. 



Imperial Institute Monographs on Mineral Resources, 

 with Special Reference to those of the British Empire. 

 Zinc Ores. (London : Imperial Institute.) 2s. 



DIARY OF SOCIETIES. 



THURSDAY. February 14. 



RovAT, Society, at 4.30.— The Artificial Production of Echinoderm T.arvse 

 with Two Water-vascular Sy<;tems, and also of Larvje Devoid of a Water- 

 vascular Svstem : Prof. E. W. MacBride.— The Quantitative Differences 

 in the Water-ronductivity of the Wood in Trees and Shrubs : Prof. J. B. 

 Farmer.— The Efficiency of Musru'ar Work • Capt. M. Greenwood. 



RovAL Society ok Arts, at 4.30— The Hide Trade and Tanning Industry 

 of India : Sir Henry Ledgard. 



Mathematical Society, at 5. — Note on Functional Fquations which are 

 Limiting Forms of Infeeral Equatif-ns : Prof. A. C. Dixon.— The Singu- 

 larities of Trochoidal Curves ; Prof. D. M. T. Sommerville.— A State- 

 ment by Fermat : L. J. Mordell. 



FRIDAY, FEnRUARY iq. 

 Royal Institution, at 5.30.— The Mechanism of the Heart : Prof. E. H. 



Starling. 

 Institution of Mechanical Engineers, at 6.— Annual General Meeting. 



—Traction on Bad Roads or Land : L. A. Legros.— Utility of Motor 



Tractors for Tillage Purposes : A. Amos. 

 Geological Society, at 5.30.— Anniversary Meeting. 



SATURDAY, February 16. 



Roval Institution, at 3.— Problems in Atomic Structure: Sir J. J. 

 Thomson. 



MONDAY. February 18. 



Royal Geographical Society, at 5.— A Transformation of the Magnetic 

 Dip Chart : E. A. Reeves. 



Royal Society of Arts, at 4.30.— The Economic Condition of the United 

 Kingdom before the War : the Real Cost of the War : and Economic Re- 

 construction : Edear Crammond. 



Aristotelian Society, at 8.— Anthropomorphism and Truth : Prof. J. B. 

 Baillie. 



Victoria Institute at 4.30.— Sun-spots and some of their Peculiarities : 

 E. W. Maunder. 



TUESDAY, February 19 



Royal Institution, at 3.— The Problems of British Anthropology : Prof. 

 A. Keith. 



Zoological 'Society, at s-3o— The Development o*" Echinncnrdium 

 eordaiutn : Prof. E. W. MacBride.— An African Civet Attacking Human 

 Beings: Capt. G. D. Hale Carpenter.- Reptiles from the River Tajan : 



Royal Statistical Society, at 5.15. — Statistics of Poland and Lithuania: 

 G. Drage. 



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

 West Quay of Madras Harbour : The Hull. Sir Francis J. E. Spring and 

 H. H. G. Mitchell. — Prutable Paper: Modern Developments in Gasworks 

 Construction and Practice : A. Meade. 



Institution of Petroleum Technologists, at 8. — A New British Oil 

 Industry : K. H. Cunningham Craig, Dr. F. MoUwo Perkin, A. G. V. 

 Perry, and Dr. A. E. Dunstan. ' 



WEDNESDA Y, February 20. 



Royal Society of Arts, at 4.30. — Picturesque Architecture : M. B. Adams. 



Geological Society, at 5.30. 



Royal Mickoscoimcal Society, at 8. — Photo-synthetic Action Induced in 

 Living Cells, and their Products: Prof. B. Moore. — Illustrations of Pre- 

 parations : Col. Rawson. 



Ro>al Meteorological Society, at 5. --The Barometer Record at the 

 Kadcliffe Observatory, Oxford, with Special Re'erence to Prof. Turners 

 Suggested Di-^c-mtinuities : F. A. Bellamy. — The Diurnal Variation of 

 Barometric Pressure at Seven British Observatories, 1871-82. A Correc- 

 tion and some Additions : Dr. C. Chree. 



THURSDAY, February 21. 



Royal Society, at 4.30. — Probable Papers: The Scattering of Light by 

 Spherical Shells, and by Complete Spheres of Periodic Structure, when 

 the Refractivity is Small : Lord Rayleigh. — The Nature of Heat as 

 Directly I 'educible froin the Postulate of Carnot : .Sir Joseph Larmor. — 

 Curved Beams: J. J. Guest.— (i) Monoclinic Double Selenates of the 

 Iron Group ; (2) Selenic Acid and Iron. Reduction of Selenic Acid by 

 Nascent Hydrogen and Hydrogen Sulphide. Preparation of Ferrous 

 Selenate and Double Selenates of Iron Group : Dr. A. E. H. Tutton. 



Institution of Electrical Engineers, at 6. — Switchgear Standardisa- 

 tion : Dr. C. C. Garrard. 



Institution of Mining and Metallurgy, at 5.30. 



Chemical Society, at 8.— Recent Studies on Active Nitrogen : Hon. R. J. 

 Strutt. 



Linnean Society, at 5. — Notes on the Bionomics, Embryology, and 

 Anatomy of Ceitain Hymenoptera Parasitica, with Special Reference to 

 Micragaster connexus, Nees : J. Bronte Gatenby. — Experimental Studies 

 in the Specific Value of Morphological Characters in the Fungi: W. B. 

 Brierley. 



SATURDAY, February 23. 

 Royal Institution, at 3. — Problems in Atomic Structure : Sir J. J. 

 Thomson. 



CONTENTS. PAGE 



Life and Work of James Geikie, By Prof, T. G. 



Bonney, F.R.S 461 



The Complete Dairy Farmer. By C. C 461 



Philosophical Idealism and Natural Science. By 



J. S. H 462 



Our Bookshelf . 463 



Letters to the Editor: — 



Flights of Rooks and Starlings.— W. B. Hardy, 

 Sec.R.S. . .... .464 



National Union of Scientific Workers.— Dr. Norman 



R. Campbell ... ..... 464 



The Green Leaf: its Scientific and Economic 



Exploitation. By F. F. B. 464 



The Adoption of the Metric System. By A. F. B. . 467 



Control of Sex in Pigeons 468 



Notes ... 469 



Our Astronomical Column : — 



Galactic Co-ordinates 473 



Molecular Scattering of Light 473 



I Leeds Astronomical Society 474 



I Wave-lengths of Helium Lines . 474 



I The Coral-reef Problem. By Prof. Grenville A. J. 



' Cole, F.R.S. 474 



A Bacterial Disease of Citrus. By E. S, S 475 



The Flora of the Somme Battlefield. By Capt. 



A. W. Hill 475 



Coal Conservation and Electric Power Supply . . 476 

 Physical Science and the Art of Experiment. By 



Prof. C. V. Boys, F.R.S. . • .... 477 



University and Educational Intelligence 478 



Societies and Academies 478 



Books Received 479 



Diary of Societies .... 480 



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Editorial Communications to the Editor. 

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 Telephone Number : Gerrard 8830 



NO. 2520, VOL. too] 



