124 



NATURE 



[March 25, 1920 



and th^ Distribution of the Principal Timber Trees. 

 By J. H. Davies. (Edinburgh : W. and A. K. John- 

 ston ; London: Macmillan and Co., Ltd.) 9>s. net. 



A Map of South America, Central America, and 

 the West Indies (on Mercator's Projection), having 

 Special Reference to the Principal Forest Regions 

 and the Chief Timber Trees. By J. H. Davies. 

 (Edinburgh : W. and A. K. Johnston ; London : 

 Macmillan and Co., Ltd.) 8s. net. 



Cytology, with Special Reference to the Metazoan 

 Nucleus. By Prof. W. E. Agar. Pp. xii+224. 

 (London : Macmillan and Co., Ltd.) 12s. net. 



Tuberculosis and Public Health. By Dr. H. Hyslop 

 Thomson. Pp. xi+104. (London: Longmans and 

 Co.) 5s. net. 



Macmillan's Geographical Exercise Books : Key to 

 Physical Geography. With Questions by B. C. 

 Wallis. Pp. 48. (London : Macmillan and Co., 

 Ltd.) 45. 6d. net. 



The Sea Fisheries. By Dr. J. T. Jenkins. Pp. 

 xxxi + agc). (London : Constable and Co., Ltd.) 24s. 

 net. 



The Flora of Chepstow. By W. A. Shoolbred 

 Pp. X+140. (London : Taylor and Francis.) 105. 6d. 

 net. 



Tvpe Ammonites. By S. S. Buckman. The Illus- 

 trations from Photographs mainlv by J. W. Tutcher. 

 Part xxi. Pp. 9-16+ 14 plates. (London: W. Wesley 

 and Son.) 



Diary of Societies. 



THURSDAY, March 25. 



Institution of Navai, Architects (at Royal Society of Arts), it 11. — 

 Sir Alfred Yarrow; Notes on our Economic Position as a Shipbuilding 

 Country. — J. Anderson : Further Notes on the Dimensions of Cargo 

 Steamers. — Dr. T. Rruhn : Freeboird and Strength of Ships. 



Institution of Naval Architects (at Royal Society of Arts), at 3. — 

 P. R Jackson: The Stabilisation of Ships by meins of Gyroscopes. — 

 Prof. iC. Suyehiro : Yawing of Ships caused by Oscillation amongst 

 Waves. 



Royal Institution op Great Britain, at 3.— Stephen Graham: The 

 Hope for Russia. 



RoYAi. SociKTY, at 4.30.— Prof. A. R. Forsyth: Note on the Central 

 OiflTerential Equation in the Relativity Theory of Gravitation. — R. D. 

 Oldham : Tlie Frequency of Earthquakes in Italy in the Years i8g6 to 

 igi4. A. F. Dufton : A New Apparatus for Drawing Conic Curves. — 

 Capt. J. W. Bispham: An Experimental Determination of the Distri- 

 bution of the Partial Correhtion Coefficient in Samples of 30. 



Chemical Society (Annual General Meeting), at 5. - Sir James J. Dobbie : 

 Presidential Address. 



RovAL College of Physicians, at 5. — Sir John R. Bradford : The 

 Clinical Experiences of a Physician during the Campaign in France and 

 Flanders, 19 4-1919 (Lumleian lecture). 



Child-Stupv Society (at Royal Sanitary Institute), at 6. — Dr. E. Sloan 

 Chesser: Adolescence and the Continuation Schools. 



Institution of Electrical Engineers (at Institution of Civil Engineers), 

 at 6 — Discussion on :— (a) The Electrical Equipment of Artisan Dwell- 

 ings (with Introductory Paper by L. Milne).' {b) The Report of the 

 Earthing Sub-Committee of the Wiring Rules Committee of the Insti- 

 tution. 



Concrete Institute, at 7.30. — E. L. Ha'l : Steehv:)rkin the new London 

 County Hall. 



Institution of Naval Architects (at Roval Society of Art.s), at 7.30. — 

 C I. R. Campbell and C. H. May : The Effect of Size upon Performance 

 of Rigid Airships. — Prof. E. G. Coker and A. L. Kemball, jun. : The 

 Effects of Holes, (racks, and other Discontinuities in Ships' Plating. 



Chemical Society (Informal Meeting), at 8. 



FRIDAY, March 26. 



Institution of Naval Architects (at Royal Society of Arts), at n.— 

 Eng.-("om. H B. Tostevin : Experience and Practice in Mechanical Re- 

 duction Gears in Warships. — J. J. King-Salter : The Balancing of Rotors 

 and Determining the Position and Amount of the Balancing Weights. — 

 Prof. T. H. Havelock : Turbulent Fluid Motion and Skin Friction. 



Physical Society of Lonoon, at 5.— Prof. A. S. Eddington and Others : 

 Discussion on E;nstein's Theory of Re'ativity. 



Wireless Society of London (at Institution of Civil Engineers^ at 6. — 

 Capt. L.A. T. Broadwood: Harmonics in Continuous Wave Transmissions 

 (Illustrated by Lantern Slides and Experiments). 



Institution of Mechanical Engineeks (Informal Meeting), at 7. — 

 P. L. Young and Others: Discussion on Foundry Memories. 



Junior Institutio.>j of Engineers, at 7.30.— W. A. Tookey: The 

 Future of the Gas Indu.stry. 



Medical Officers of Schools .Association (at 11 Chandos Street, 

 W.), at 8. —Dr. G. H. Lock and Others : Discussion on Care of Minor 

 Ailments in School Children. 



Royal Society of Medici.se (Epidemiology and State Medicine Section), 

 at 8.30. — Dr. S. Monckton Copeman : The Relationship of Smallpox 

 and Alastrim. 



Royal Institution of Great Britain, at 9. — Sir J. J. Thomson : The 

 Scientific Work of the late Fhe Right Hon. Lord Rayfeigh. 

 SATURDAY, March 27. 



Royal Institution of Great Britain, at 3. — Sir J. J. Thomson : 

 Positive Rays. 



MO If DA Y, March 29. 



Institution of Automobile E>joineers (Graduate Section), at 8. — 

 W. D. Pile : The Use of Benzol. 



Royal Institute of British Architects, at 8. — Delis.sa Joseph: 

 Higher Buildings (or London. 



Royal Geographical Society (at ^Eolian Hall), at 8.30. — Commander 

 D. G. Hogarth : War and Discovery in Arabia. 



TUESDAY, March 30. 



Technical Inspection Association (at the Royal Society of Arts), at 

 5. — Annual General Meeting. 



Zoological Society of London, at 5.30.— Sir Frank Colyer : Exhibition 

 of Skulls of Macacus t hesus.—DT. C. F. Sonntag : Abnormalities of the 

 Abdominal Arteries of a Young Panda. — A. Loveridge : Noies on East 

 African Lizards collected 1915-1919, with Descriptions of a new Genus 

 and Species of Skmk, and a new Subspecies of Gecko.— A. M. Altson : 

 The Life-history and Habits of Two Parasites of the Blowfly. 



Royal Photographic Socik.ty of Great Britain (Lantern Meeting) 

 at 7.— E. W. H. Piper : Gloucester Cathedral. 



Illuminating Engineering Society (at Koyal Society of Arts), at 8.— 

 J. W. T. Walsh and Others : DLscussion on Motor-car Headlights in 

 rela;tion to Traffic Requirements. 



Rontgen Socikty (in X-ray and Electrical Departments, St. Bartholo- 

 mew's Hospital), at 8.15. 



CONTENTS. PAGE 



Knowledge and Power 93 



Aeronautical Research 95 



Gymnospermic History 97 



The Nature of Musical Sound 98 



Science of Food. By W. D. H 99 



Out Bookshelf •• • 99 

 Letters to the Editor: — 



Museums and the State.— Sir E. Ray Lankester, 

 K.C.B., F.R.S. ; Prof. J. Stanley Gardiner, 



F.R.S. ; Dr. W. M. Tattersall 100 



Organisation of Scientific Work. — Sir T. H. 



Middleton 103 



Science and the New Army. — Col. E. H. Hills, 



C.M.G., F.R S 103 



Cotton-growing in the British Empire. — Dr. W. 



Lawrence Balls ; Sir George Watt .... 103 

 The Separation of Isotopes. — Dr. Thomas R. 



Merton and Brig. -Gen Harold Hartley . . 104 

 Calendar Reform.— Camille Flammanon ; Dr. 



A. C. D. Crommelin 105 



On Langmuir's Theory of Atoms. — Dr. A. E. Oxley 105 

 Fireball of February 4.— M. L. Dey ; W. F. 



Denning . 105 



Buzzards and Bitterns.— Rev. Canon Edmund 



McClu^e • 105 



Ostrich Study in South Africa. (Illustrated.) By 



Prof. J. E. Duerden 106 



The Conservation of Our Coal Supplies. By Prof. 



J. W. Gregory, F.R.S 108 



Obituary no 



Notes 112 



Our Astronomical Column : — 



The Total Sular Eclipse of 1918 June 8 117 



A Noon Reflector 117 



American Fossil Vertebrate Animals. (Illustrated.) 



By A. S. W 117 



Research in Textile Industries 118 



Climatology of North-West Russia and France. By 



J. S. D 119 



Volumetric Testing of Scientific Glassware .... 120 



University and Educational Intelligence .... 120 



Societies and Academies • • • 121 



Books Received 123 



Diary of Societies .... 124 



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Editorial Communications to the Editor. 



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Telephone Number : Gerrard 8830. 



NO. 2630, VOL. 105] 



