46o 



NATURE 



[February 7, 1918. 



tions of a new genus and four new species from the ' 

 coast of New South Wales. — H. J. Carter: Some new 

 Heteromera and a new Stigmodera (Coleoptera) from 

 tropical Australia.— Prof. W. N. Benson ; The geology 

 and petrology of the Great Serpentine Belt of New- 

 South Wales. Appendix to part vi. — Dr. H. S. H. 

 Wardlaw : The variability of cows' milk. Samples of 

 afternoon milk from 109 healthy cows kept under 

 similar conditions, but of various ages, breeds, and 

 stages of lactation, were examined. Certain physical 

 properties, the composition, and quantities secreted in 

 eight hours were determined. The variabilities of the 

 results fall into four distinct groups. The percentages 

 of results lying within five of the mean, and the per- 

 centage-deviation from the mean within which prac- 

 tically all the results lay, were: — (i) Freezing point 

 and density, 100; 5 ; (2) electrical conductivity and con- 

 centration of soluble matter (chiefly lactose), 50, 25 ; 

 (3) concentration of matter not in solution (chiefly fat 

 and protein), 20, 50; (4) quantities secreted in eight 

 hours, 10, 100. Only three samples contained less than 

 3-2 per cent, of fat, while more than 40 per cent, of 

 the samples contained less than 8-5 per cent, of 

 solids not fat. — Miss E. C. Pinkerton : The composition 

 of expired alveolar air. Estimations of the percentage 

 of oxA'gen and carbon dioxide in the successive portions 

 of air rapidly expelled from the lungs show that the 

 concentration ot carbon dioxide diminishes by not more 

 than 0-22 per cent, in the final 600 c.c. respired, and 

 that the concentration of oxygen increases by not more 

 than 0-36 per cent, in the same portion of the breath. The 

 change in concentration is independent of the depth of 

 respiration, but depends on the speed with which the 

 air is expired ; the more slowly the air is breathed out 

 the greater the change in concentration of the gases of 

 the final portion. The results obtained lead to the 

 inference that the alveolar air in the pulmonary atria, 

 at the end of an expiration, contains a lower concentra- 

 tion of oxygen and a higher concentration of carbon 

 dioxide than the air last expelled from the mouth in 

 the rapid expiration. 



BOOKS RECEIVED. 



The Principles and Practice of Pruning. By M. G. 

 Kains. Pp. xxv + 420. (New York: Orange Judd 

 Co.) 2 dolla»-s net. 



Comment Economiser le Chauffage Domestique et 

 Culinaire. By R. Legendre and A. Thevenin. Pp. 

 123. (Paris: Masson et Cie.) 1.25 francs. 



The Rural Teacher and his Work in Community 

 Leadership, in School Administration, and in Mastery 

 of the School Subjects. By H. W. Foght. Pp. xii4- 

 359. (New York : The Macmillan Co. ; London : Mac- 

 rhillan and Co., Ltd.) 75. 6d. net. 



Manual of Milk Products. "By Prof. W. A. Stock- 

 ing. Pp. xxvii + 578. (New York: The Macmillan 

 Co. ; London : Macmillan and Co., Ltd.) los. 6d. net. 



La Statique des Fluides, la Liquefaction des Gaz et 

 ITndustrie du Froid. By E. H. Armagat and L. 

 Decombe. Premiere et Deuxi^me Partie. Pp. vi+ 

 265. (Paris and Liege : Ch. Beranger.) 18 francs. 



DIARY OF SOCIETIES. 



THURSDAY, Ffbruary 7. 

 Royal Socif.ty, at 4.TO.— The Photo-EIectric Action of X-rays: Prof. 



O. W. Richardson.— The Parent of Actinium : Prof. F. Soddy and J. A. 



Cranston.— Some Problems in the Theory of Radiation : Prof. A. Schuster. 



—The Absorption of the Radiation Emitted by a Palladium Anticathode 



in Rhodium, Palladium, and Silver : E. A. Owen. 

 Royal iNSiitUTiON, af ^.—Illusions o<" the Atmosphere : The Travelling 



Vortex and the Cyclonic Depression : Sir Napier Shaw. 

 In.stitution of Electrical Engineers, at 6.— Ninth Kelvin Lecture: 



Kelvin as a Teacher : Prof. M. Maclean.' 

 Linnean Society, at 5.— Two Biblioeraphical R.-irities of the Society's 



I.ibrarv : («) Cupani, F., "Panphyton siculum," 1713 ; {b) Du Gort, 



J. and P., "L'Histoire et Pourtrait des Plantes," Lyon, 1561: The 



General Secretary.— Plant Distribution from the Standpoint of an Idealist : 



H. P. Guppy. 



Chemical Society, at 8.— Atomic and Molecular Numbers: H. S. Allen 

 — Studies of the Carbonates. IV. The Hydrolysis of Sodium Bicarbonate 

 and the lonisation Constants of Phenolphthalein : C. A. Seyler and 

 E. H. Tripp.— Some Inorganic Stanrichlorides : J. G. F. Druce. — A Re- 

 investigation of the Cellulose-dextrose Relationship : Miss M. Cunningham. 

 — Esparto-cellulose and the Problem of Constitution : C. F. Cross and 

 E. J. Sevan. 



FRIDAY, February 8. 



Royal In.stitution, at 3.30.— Science and Ethics: Principal E. H. 

 Griffiths. 



Royal Astronomical Society, at 5. — Anniversary Meeting. 

 SATURDAY, Yv.v.YL\3^.^s c,. 



Royal Institution, at 3.— The Ethics of the War : P. H. Loyson. 

 MONDAY, February ii. 



Royal Geographical Society, at 8.30. — The London Society's Map with 

 its Proposals for the Improvement of London : Sir Aston Webb. 



Society of Engineers, at 5.3o.^Presidential Address : W. B. Esson. 

 TUESDAY, February 12. 



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

 A. Keith. 



WEDNESDAY, February 13. 



British Association Geophysical Discussions (Royal Astronomical 

 Society), at 5. — The Influence of Barometric Pressure on Mean Sea-level : 

 Sir C. F. Close. — Precise Levelling : Major Henrici. 



Royal Society of Arts, at 4.30.— The Relations between Capital and 

 Labour — Reasonable Hours, Co-partnership, and Efficiency : Lord Lever- 

 hulme. 



THURSDAY, February 14. 



Royal Society, at ^.-^a.— Probable Papers: The Artificial Production of 

 Echinoderm Larvje with Two Water-vascular Systems, and also of Larvae 

 Devoid of a Water-vascular System : Prof. E. W. MacBride.— The Quan- 

 titative Differences in the Water-conductivity of the Wood in Trees and 

 Shrubs : Prof. J. B. Farmer. — The Efficiency of Muscular Work : Capt. 

 M. Greenwood. 



Royal Society of Arts, at 4.30.— The Hide Trade and Tanning Industry 

 of India : Sir Henry Ledgard. 



FRIDAY, February 15. 

 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. 



SATURDAY, February 16. 

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

 Thomson. 



CONTENTS. PAGE 



Biology from America. By J. A. T 441 



School-life in the Seventeenth Century. By A. H, 442 



Organic Chemical Analysis. By C. S 443 



Our Bookshelf 444 



Letters to the Editor: — 



The British Scientific Instrument-making Trade. — 



E. S. Hodgson 444 



The National Food Policy 445 



The Investigation of Industrial Fatigue. By Prof. 



W. M. Bayliss, F.R.S. 446 



Germany and Iron-ore Supplies. By H. L 447 



Notes " 447 



Our Astronomical Column : — 



Luminosities and Parallaxes of 500 Stars 451 



Solar Hydroj^en Bombs 45 1 



" Annuaire du Bureau des Longitudes " 452 



Third Melbourne Star Catalogue ... . 452 

 The Endowment of University and Technical 



Education . . 452 



Magnetic Survey of New Zealand. By Dr. C. 



Chree, F.R.S. . . . . 453 



Parasites of Crops and Cattle . 454 



Light and Vision. By A. P. Trotter 454 



Science and the Cold-storage Industry. By Prof. 



J. Wemyss Anderson 455 



University and Educational Intelligence 456 



Societies and Academies 457 



Books Received , . . . . 460 



Diary of Societies 460 



Editorial and Puhlishing Offices: 

 MACMILLAN AND CO., Ltd., 

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



Advertisements and business letters to be addressed to the 

 Publishers. 



NO. 2519, VOL. 100] 



Editorial Communications to the Editor. 

 Telegraphic Address .' Phusis, London. 

 Telephone Number : Gerrard 8830. 



