NATURE 



[November 25, 1915 



group of cells as a whole thus is defined some time 

 before differentiation becomes visible. — C. G. Bull : A 

 mechanism of protection against bacterial infection. 

 Bacteria circulating in the blood are quickly removed 

 when they are agglutinated or clumped, and the 

 clumps deposited within the organs are taken up by 

 phagocytes and digested. They appear not to be 

 destroyed by solution or lysis through the operation 

 of serum constituents of the blood. — C. A. Kofold and 

 Elizabeth B. Christiansen : The life-history of Giardia. 

 Giardia muris and Giardia microti produce a readilv 

 recognisable enteritis in mice, and both binary and 

 multiple fission take place in" the free non-encysted 

 stage. There is no Octomitus stage. The morpho- 

 logical characters separate six species. The parasite 

 in mice appears to be distinct from that in man. — 

 F. W. Clarke and W. C. Wheeler: The stony corals 

 have been repeatedly analysed and with generally con- 

 cordant results. Thirty analyses here made have con- 

 firmed the older data. The object of the investigation 

 is to determine what each group of organisms con- 

 tributes to the formation of marine limestones. The 

 highest proportions of calcium phosphate are com- 

 monly associated with high values for mag'nesia.^ — 

 C. R. Stockard : An experimental analysis of the origin 

 and relationship of blood corpuscles and the lining 

 cells of vessels. Vascular endothelium erythrocytes 

 and leucocytes, although all arise from mesenchyme, 

 are really polyphyletic in origin ; that is, each has a 

 difTerent mesenchymal anlage. 



BOOKS RECEIVED. 



Scientific Ideas of To-day. By C. R. Gibson. 

 Fifth edition. Pp. 344. (London : Seeley, Service and 

 Co., Ltd.) 5A-. net. 



Mathematics for Machinists. By R. W. Burnham. 

 Pp. viii + 22g. (New York: J. Wiley and Sons, Inc.; 

 London : Chapman and Hall, Ltd.) 55, 6d. net. 



Determinative Mineralogy, with Tables for the 

 determination of Minerals by Means of their Chemical 

 and Physical Characters. By Prof. J. V. Lewis. Pp. 

 vii + 155. (New York: J. Wiley and Sons, Inc.; Lon- 

 don : Chapman and Hall, . Ltd.) 65. 6d. net. 



Properties of Steam and Ammonia. By Prof. G. A. 

 Gbodenough. Pp. vii-fio8. (New York: J. Wiley 

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

 5s. 6d. net. 



Wisconsin Geological and Natural History Survey. 

 Bulletin No. xlv. Economic Series. No. 20 : The 

 Peat Resources of Wisconsin. By F. W. Huels. Pp. 

 xvii + 274. (Madison, Wis.) 



Tuberculosis : a General Account of the Disease, its 

 Forms, Treatment, and Prevention. By Dr. A. J. 

 Jex-Blake. Pp. viii + 231. (London: G. Bell and 

 .Sons, Ltd.) 2s. 6d. net. 



c»l/\K* Ot SOCIETIES. 



THURSDAY, November 25. 



Royal Society, at 4.— Special General Meeting to rective the Annual 

 Report of Counril : at ^1.30.— The Measurement of the Kate of Heat Loss 

 at B'idv 'I empe'-atur-- by Convection, Radiation and Evaporation: 

 M. Flack, O. W. Griffith and L. Hill.— The Growth of the Body in Man ; 

 The Relationship bciwc,:n the Body Weight and the Body Length (Stem 

 Length) E. W. A Walker.— 1 he Rate of Ab-orption of Various Pheno- 

 lic Solutions by Sreds of Hordcum vulgare and the Factors Governing 

 the Kate 01 Diffusion . f Aqueous Solutions across the Semi-permeablie 

 Membranes: Prot. A. J. Brown and F. linker.— The Controlling 

 Influx mr of Carbonic Hioxide. Part IIL The Retarding Eflfect of Car- 

 bon Dioxide on Respiration : F. Kidd. 



Institution op Electkical Engineers, at 8.— Some Difficulties of 

 Design of Hith-spced Generaiors : Prof. A. B. Field. 



Optical Society, at 8.— The Influence of Visual Errors in Musketry : 

 J. H. Sutclitle. 



HRIDAY, November 26. 



Physical Society, at 5. -Obtaining and Maintaining a Bright Hydro- 

 gen Spectrum, with -special reference to the 4341 Line: J. Guild.— 

 Determ nittiim ot ihe Coefficient of Diffusion of Potassium Chloride by 

 an Analytical Method Dr. A. Griffiths.— Apparatus for Evaluating 

 Elliptic Integrals : A. F. Ravenshear. 



MONDAY, November 29. 



Royal Society of Arts, at 4.30.— Optical Glass: Dr. W. Rosenhain. 



Mkuical Society, at 8.30.— Gas Poisoning : Physiological Symptoms and 

 Clinical Treatment: Dr. Leonard Hill. 



RovAL Geograi-hical Society, at 8.30.— The Railway Development of 

 Africa, Present and Future : Sir Charles Metcalfe, Bart. 

 TUESDAY, November 30. 



Royal Society of Arts, at 4.30. — Recent Developments in Jamaica; 

 Internal and External : Sir Sydney Olivier. 



Institution of Civil Engineers, at 5.30. — Harbour and Coast-Defence 

 Works at Alexandria : D. E. Lloyd-Davie.s. — Galvan Port, Bahia Blanca, 

 Argentine : C. A. Trery. 



WEDNESDAY, December i. 



Royal Society of Arts, at 4.30.— Insects and ^yar: Dr. A. E. Shipley. 



Geological Society, at 5.30. — The Petrological Microscope; New or 

 Little-known Methods and Accessories : Dr. J. W. Evans. 



Entomological society, at 8. 



Society of Public Analysts, at 8. — The Microchemistry of seme Alka- 

 loids : Dr. G. D. Lander.— The " Presumptive Coli Test " on Uiichilled 

 Water : W. Partridge : Notes on Methods of Analysing Oleaginous 

 Seeds and Fruits : E. R. Bolton. 



THURSDAY, December 2. 



Royal Society, at ^.y:>.— Probable Papers: Note on the Existence of 

 Converging Sequences in certain Oscillating .Successions of Functions: 

 W. H. Young. — Ihe Emulsifying Action of Soap ; a Coniribution to the 

 Theory of betergcnt Action : S. A. Shorter and S Ellingworth. — The 

 Newtonian Constant of Gravitation as affected by Temperature : P. E. 

 Shaw. — Skin Friction of the Wind on the Earth's Suiface : G. I. Taylor. 

 FRIDAY, December 3. 



Geologists' Association, at 7.30.— Some Features of the Antarctic Ice: 

 J. D. Falconer. 



CONTENTS. PAGE 



Science and the Public 335 



Two More Bantu Books. By Sir H. H. Johnston, 



G.C.M.G., K.C.B 336 



Finite Differences for Actuaries 337 



Practical and Applied Chemistry. By T. M. L. . . 338 



Our Bookshelf 339 



Letters to the Editor: — 



Pre-Columbian Representations of the Elephant in 

 America. (///?«/ra/^^.)— Prof. G. Elliot Smith, 



F.R.S 340 



Commercial Firms and Scientific Inventors. — Prof. 



G. H. Bryan, F.R.S 34J 



The Aurora Borealis of November '5. — ^J. ; Rev. 



A. L. Cortie, S.J -342 



A Remarkable Solar Halo.— Prof. David Robertson 342 

 Rule for Determining Direction of Precessional Move- 

 ment.— Piof. A. Gray, F.R.S 342 



Scientific Exposition at its Best. {Illustrated.) . . 342 

 John Dalton as a Science Lecturer. By dir T. E, 



Thorpe, C.B., F.R.S 344 



Prof. Raphael Meldola, F.R.S. By W. A. T. ; 



E. B. P 345 



Dr. H. Charlton Bastian, F.R.S. By R. T. H. , . 347 



Notes 34S 



Our Astronomical Column :— 



The December Meteoric Shower 352 



Comet 1915a? Mellish 353 



Visibility of Mercury 353 



The Light-curve of RZ Cassiopeiae ........ 353 



Recent Scientific Work in Italy. By W. A. D. , . 353 



Physiology at the British Association 354 



Botany at the British Association 355 



Agriculture at the British Association 357 



University and Educational Intelhgence 359 



Societies and Academies 360 



Books Received 362 



Diary of Societies . . . • 362 



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Editorial Communications to the Editor. 

 Telegraphic Address: Phusis, London. 

 Telephone Number : Gerrard 8830. 



