524 



NATURE 



[December i6, 1920 



Hudson. Pp. vii + 2a5. (London and Toronto: J. M. 

 Dent and Sons, Ltd. ; New York : E. P. Dutton and 

 Co.) 7i. 6d. net. 



Optical Methods in Control and Research Labora- 

 tories. Pp. 30. (London : Adam Hilger, Ltd.) 

 IS. 6d. net. 



A System of Physical Chemistry. Bv Prof. 

 W. C. McC. Lewis. (In 3 vols.) Vol. ii. : thermo- 

 dynamics. Third edition. Pp. viii + 454. (London : 

 Longmans, Green and Co.) 15s. net. 



Department of Scientific and Industrial Research. 

 .'Vdvisory Council. Report of the Lubricants and 

 Lubrication Inquiry Committee. Pp. 126+3 plates. 

 (London: H.M. Stationery Office.) 2.9. 6(i. net. 



Department of Scientific and Industrial Research 

 Food_ Investifrntion Board. Special Reoort No. 4. 

 Interim Report on Methods of Freezing Fish, with 

 Special Reference to the Handling of Large Quanti- 

 ties m Gluts. Pp. 50 + 4 plates. (London : ~ H.M. 

 Stationery Office.) ix. 6d. net. 



Benzol : Its Recovery, Rectification, and Uses. 

 By S. E. Whitehead. Pp. xiv+20Q. (London : Benn 

 Bros., Ltd.) \2s. 6d. net. 



,Tr^'^j^^"'^''"^ Nation. By Basil A. Yeaxlee. (The 

 World of To-day.) Pp. 80. (London : Oxford Uni- 

 versity Press.) 2s. 6d. 



Never Grow Old: How to Live for more than 

 One Hundred Years. By Dr. L. H. Goizet. Pp. lo,. 

 (New York and London : G. P. Putnam's Sons ) 

 lox. net. 



Zoology : An Elementary Text-book. Bv Sir A E. 

 Shipley and Prof. E. W. MacBride. Fourth edition. 

 Pp. xx+752. (Cambridge : At the University Press.) 

 20s. net. ' 



Countryside Rambles. Bv W S Furneaux 

 Pp. lvi+186. (London: G. "Philip and Son, Ltd.) 

 3s. 6d. net. ' 



Psychology and Mystical Experience. Bv Prof J 

 Howley Pp. xi + 27s. (London : Kegan 'Paul ard 

 Co., Ltd. ; St. Louis, Mo. : B. Herder Book Co.) 

 los. 6d. net. 



Mineralogy : An Introduction to the Study of 

 Minerals, and Crystals. By Prof. E. H. Kraus and 



P""- .^^- ?"; i^""*- PP- xiy+561. (New York and 

 London : McGraw-Hill Book Co., Inc.) 27.?. 



Geology of the Non-Metallic Mineral Deposits other 

 than Silicates. Bv A. W. Grabau. Vol. i. : Prin- 

 ciples of Salt Deposition. Pp. xyi + 435. (New York 

 and London : McGraw-Hill Book Co., Inc.) 305 



Diary of Societies. 



TBVRSDAT, Dicehbes 16. 

 RorAl SociETl or JIedicise (Dermatology Section) at 5 



H%fr.H!l*"p"''M°"n" ,'*' ^-•^»' S'x'i^ty of Arts),' at 5.30.- 

 H. nicardo : Possible Developments in Aircraft Eugines.-A J 

 Rowledge: The Instalment of Aeroplane Engines 

 ^'?7'Jon""'f °T ^1'^'"° c*"" ""*i-"KOT (at Geological Society), 

 Tr^'stfipp'iSL Mo^th'T' Observations on Mining by the Openeaft 



^Tn'J/'„V,°JI> °Jf J'^n""""-^™;"'""^ <^* Institution of Civil 

 Cables S.-Disoussion : Report on the Heating of Buried 



Concrete Institute, at 7.30.-H. J. Deane : Special Applications 



of Reinforced Concrete in Docks, with Special Reference to ?Se 



Reinforced Concrete Gates at Tilbury Docks. 

 INSTITCTION or ArTOMOBiiE ES0INEEB3 (Graduates' Meeting) (at 



28 Victoria Street), at 8.-T. E. B. Whiting: Carburation 

 Chemical Societt (at Institution of Mechanical Engineers) at 8 — 



Sir R, Robertson : Lecture : Some Properties of Explosives. 

 ROktgen SociETl (in Physics Lecture Theatre, University College) 



at S.lo.—The Reduction of Radiographic Exposures to 1 '2ath 



and Less by Means of a New Type of X-Rav Plate. Part I. 



by Dr. L. Levy and D. W. West. Part II. by T. Thorne Baker. 

 HiBTEiAH Society of London (at 11 Chandos Street, W.), at 8 30 — 



Dr. C. M. Wilson, Dr. C. Buttar, and Others : The Future of 



the Poor-law Infirmary. 



NO. 2668, VOL. 106] 



FRIDAY, OtcrauH 17. 



Socinr or Uidical OrrjcEBa or Health (at 1 Upp«r Montague 

 Street), at 5.— Lt.-Col. H. 11. Kenwood : Presidential Address to 

 the Navy, Array, and H.A.F. Hygiene Group of the Society. 



Institution or Mechanical Enoineebs, at 6.— IJr. W. J. Walker- 

 Thermodynami'o Cycles in Relation to the Design and Future 

 Development of Internal-combustion Motors. 



JCNiott iNSTiicTioN OE Enoiniees (at Royal United Service In- 

 stitution), at 7.30.— Lord Weir of Eastwood: Some JUaections on 

 our Industrial Situation (Presidential Address). 



RoTAL .sociEir or Aets, at 8.— Col. R. J. Stordy : The Breeding of 

 Sheep, Llamas, and Alpacas in Peru, with a view to supplying 

 Improved Raw Material for the Textile Trades. 



RoiAL .Societt of Medicine (Elentro-Therapeutioa Section), at 

 8..30.— Adjourned Discussion : Radio-Therapy.— Dr. R. Morton : 

 Recent Developments in Deep Therapy.— Dr. L. Martindale : 

 Technique of X-ray Therapy of Fibroids. 



Rotal Societi or Thopical Medicine and Htoiene (at London 

 School of Tropical Medicine), at 8.30.— Laboratory Meeting. 



SATURDAY, Decembek 18. 

 Fhisiolooical Societt (at St. Thomas' Hospital), at 4. 



MONDAY, Deceubeb 20. 



SuEVETOEs' Institution, at 7.— H. 8. Logsdon : Hating as affected 

 by Recent Legislation. 



Aristotelian Societi (at University of London Club, 21 Oower 

 Street), at 8.— Prof. T. P. Nunn and Prof. H. Wildon Carr : Dis- 

 cussion on Prof. Alexander's " Space, Time, and Deitv." 



RoiAL Societt of Aets, at 8.— A Chasten Chapman: Micro- 

 organisms and Some of their Industrial Uses (Cantor Lecture I. 



Institution or Automobile Enoineebs (London Graduates' Meet- 

 ing) (at 28 Victoria Street), at 8.— W. H. Wardall : Cylinder and 

 Piston Wear. 



RoTAL Geoobaphical Societt (at .?!olian Hall), at 8.30.— F. Dcben- 

 ham : The Future of Polar Research. 



TUESDAY, Decembeb 21. 



Rotal Societt or Medicine, at 5. — General Meeting of Follows. 



Rotal Photogeaphic Societt or Great Britain, at 7.— Dr. D- J. 

 Reid : Further Developments in Systematic Exposure in Photo- 

 micrography. 



CONTENTS. 



PAGE 



• 493 



■ 494 



496 



- 497 



- 498 



The Practical Teaching of Science 



Vitalism versus Mechanism. Bv J. J 



A Study of Weeds. By A. D. H. 



Facts and Theories for the Social Worker . . 



Our Bookshelf 



Letters to the Editor: — 



Heredity and Acquired Characters. — Sir E. Ray 

 Lankester, K.C.B., F.R.S. ; Prof. E. W. 



MacBride, F.R.S ... 500 



The Energy of Cyclones. (Wilh Diagram.) — R. M. 



Deeley , . 502 



Name for the Positive Nucleus. — Prof. Frederick 



Soddy, F.R.S 502 



The Stereoscopic Appearance of Certain Pictures. — 



A. P. Trotter -.503 



Luminosity by Attrition. — ^James Weir French 503 



Traqic Death Feint of a Snake.— Dr. W. E. 



Bartlett. 503 



The Alkaloids of Senecio jacobaea. — Dr. A. H. 



Mac Kay • .... 503 



Instruments for the Navigation of Aircraft. (Illus- 

 trated ) By G. M. B. Dobson 504 



Industrial Research Associations. VI. The Glass 

 Research Association. By Edward Quire 506 



The Quantum Theory ..'.... 508 



Obituary : — 



Spencer Pickering, F.R.S. By A. D. H. ... 509 



William Arthur Haward 510 



Notes .... 511 



Our Astronomical Column : — 



Tidal Friction and the Lunar Acceleration 515 



The Solar Spectrum from 65(Xi A. to 9000 A. . . . 515 

 Anthropology at the British Association. By 



E. N. F. ... 516 



Smoke Abatement and Hous'ng Schemes. By 



J- B. C 517 



Work of the Analytical Laboratory, Cairo .... 51 



The Problem of Soaiing Flight 518 



University and Educational Intelligence . 518 



Societies and Academies ... 520 



Books Received .... . . 523 



Diary of Societies 524 



