i6o 



NATURE 



[October 25, 1917 



Mixed phthaleins, containing two different phenol resi- 

 dues, one of which is CeH.-OH, are made with extra- 

 ordinary ease by boiling ^araoxybenzophenone-o-carb- 

 oxylic acid with any phenol or amine, whether free 

 or substituted. The spectra of eighteen new phthaleins 

 of this class are described^ and the laws governing 

 the colour elucidated. The method is an excellent 

 analytical one for identifying phenols and amines and 

 their ethers and derivatives. The spectrum of phenol- 

 thymolphthalein is not exactly half-way between those 

 of phenolphthalein and thymolphthalein. The spectra 

 of live sulphonephthaleins made from "saccharin" are 

 also described, also six more new^ derivatives of 

 ordinary phenolphthalein. A new general formula 

 for the coloured substances is put forward. — J. R. 

 Sutton : Kimberley diamonds, ' especially cleavage dia- 

 monds. This paper is a general and statistical account 

 of the diamonds produced in the mines under the con- 

 trol of the De Beers Company at Kimberley. It de- 

 scribes the outstanding differences in size, colour, and 

 type between the yields of the different mines; speaks 

 of coloured diamonds, bort, and, especially, cleavage 

 diamonds ; and advances the view that many diamonds 

 have been naturally broken by the unequal expansion 

 of themselves and mineral inclusions. It appears that 

 brown diamonds have shown a particular disposition to 

 come up broken from the deeper levels of the Wessel- 

 ton mine (though the ratio of colourless cleavage to 

 colourless stones also increases with depth of mining), 

 but the author doubts the common assertion that brown 

 or smoky diamonds are markedly liable to spontaneous 

 fracture. — S. Schonland : The phanerogamic flora of the 

 divisions of Uitenhage and Port Elizabeth. This paper 

 is meant to be a companion to the papers published by 

 the late Dr. Bolus and Major Wolley Dod on the 

 flora of the Cape Peninsula, and by the late Dr. J. 

 Medley Wood on the flora of Natal. There are 2290 

 species recorded, of which ninety-eight are considered 

 by the author not to be native. They are distributed 

 over 128 natural orders and 712 genera. Tl)ere are, 

 however, still large tracts of this area unexplored. 

 Most of the localities quoted are contained in about 

 600 sq. miles, while the total area is about 2500 sq. 

 miles ; much of the remaining tract is, however, covered 

 by fairly uniform karroid succulent vegetation. — J. R. 

 Sutton : A lunar period in the rates of evaporation and 

 rainfall. This paper directs attention to the possibility 

 of a lunar influence governing the evaporation from a 

 water surface, and a lunar period in the incidence of 

 rainfall. Tables are given showing that as the result 

 of hourly observations of evaporation and rainfall dur- 

 ing the 120 lunar months from August, 1899, to April, 

 1909, rainfall has its maximum frequency about the. 

 time of moonrise, and its minimum just after moon- 

 set; also that the rate of evaporation has a maximum 

 and minimum, respectively, shortly after the moon 

 passes the meridian above and below the horizon. 



BOOKS RECEIVED. 



Two Summers in the Ice-Wilds of Eastern Kara- 

 koram. By F. B. and W. H. Workman. Po. 296 + 3 

 maps + illustrations. (London: T. Fisher Unvvin, Ltd.) 

 255. net. 



University of London. University College. Abridged 

 Calendar. Session 1917-18. (London : Taylor and 

 Francis.) 



The Pasteurization of Milk from the Practical View- 

 point. By C. H. Kilbourne. Pp. iv + 248. (New 

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

 and Hall, Ltd.) 6s. net. 



Modern Propagation of Tree Fruits. By Prof. B. S. 

 Brown. Pp. xi+174. (New York: J. Wiley and 

 Sons, Inc. ; London : Chapman and Hall, Ltd!) 65. 

 net. 



Elliptic Integrals. By Prof. H. Hancock. Pp. 104. 

 j (Mathematical Monogra'phs, No. 18.) (New York: J. 

 I Wiley and Sons, Inc. ; London, Chapman and Hall, 

 Ltd.) 6s. net. 



A Text-Book of Inorganic Chemistry. By Prof. 

 A. F. Holleman. Issued in English in co-operation 

 with H. C, Cooper. New edition. Pp. viii + 507. 

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

 man and Hall, Ltd.) 105. 6d. net. 



Dairy Cattle Feeding and Management. By Profs. 

 C. W. Larson and F. S. Putney. Pp. xx + 471. (New 

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

 and Hall, Ltd.) 115. 6d. net. 



Rustic Sounds and other Studies in Literature and 

 Natural History. By Sir F. Darwin. Pp. 231. (Lon- 

 don : J. Murray.) 65. net. 



The Faith of a Farmer : Extracts from the Diary 

 of William Dannatt, of Great Waltham. Edited, with 

 an Introduction, by J. E. G. de Montmorency. Pp. 

 xliii + 249. (London : J. Murray.) 55. net. 



DIARY OF SOCIETIES. 



FRIDAY, October 26, 



Physical Society, at ■;. — A Class of Multiple Thin Objectives : T. Smith. 

 — The Radius of the Electron, and the Nuclear Structure of Atoms : Prof. 

 J. W. Nicholson. 



THURSDAY, November i. 



Royal Society, at 4.30. — Probable Papers : The Reflexion of Light from 

 a Regularly Stratified Medium : Lord Rayleigh. — Two Cases of Congenital 

 Night-blindness : Sir William Abnev. — Duration of Luminosity of Electric 

 Discharge in Gases and Vapours. Further Studies : Hon. R. J. Strutt. — 

 Surface Reflexion of Earthquake Waves : G. W. Walker.— Characteristic 

 Frequency and Atomic Number : Dr. H. S. Allen. 



CONTENTS. PAGE 



A Retrospect of Modern British Science 141 



The Rarer Elements. By J. H. Gardiner . ... 142 



The Study of Uife. By D. W. T 143 



Our Bookshelf . 143 



Letters to the Editor:— 



Transparency of the Atmosphere for Ultra-violet 



Radiation.— Hon. R. J. Strutt, F.R.S. . 144 

 The Cure of the Isle of Wight Disease in the Honey 



Bee. — E. E. Lowe . ... 144 



'Tidal Energy Dissipation.— R. O. Street . . 145 



Stereo-Radioscopes.— Harry W. Cox and Co., Ltd. 146 

 An Optical Phenomenon. — C. Carus- Wilson ; 



H. M. Atkinson 146 



Infant and Child Mortality. By R, T. H. . . 146 



The Study of a Genus of Land-snails. By S. J. H. 148 



Continuative Education and its Objects. By A. D. 148 



Notes 149 



Our Astrnnomical Column :— 



The Hunter's Moon 154 



The Orbit of Comet 19146- 154 



Maximum of Mira Ceti 154 



Brester's Theory of the Sun 154 



! The New Physics. By G. B. M 155 



I Meteor Orbits 155 



! Geology of the Witwatersrand Gold Field . . • 156 

 j Organised Knowledge and National Welfare. By 



I Dr. P. G. Nutting 156 



I University and Educational Intelligence 158 



! Societies and Academies 159 



I Books Received 160 



! Diary of Societies i6o 



Editorial and Publishing Offices : 



MACMILLAN AND CO., Ltd., 



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



Advertisements and business letters to be addressed to the 

 Publishers. 



NO. 2504, VOL. 100] 



I Editorial Communications to ihe Editor 



I Telegraphic Address : Phusis, London. 

 Telephone Number : Gerrard 8830. 



