506 SCIENCE PROGRESS 



book under review the authors have endeavoured to fill this gap in the literature 

 by dealing systematically not only with the methods of determination of the forty 

 less common elements but also with the methods of separation of such groups of 

 these as are likely to occur in the various ore-minerals. After a preliminary 

 chapter on mineral-analysis, the elements are considered, in the order of the 

 periodic table, under the following heads : minerals, properties and compounds, 

 quantitative separation, methods of determination, detection and determination in 

 ores, and complete analysis of ores. 



The weakest part of the book is the section on mineralogical analysis, despite 

 the fact that the authors emphasize the necessity of a knowledge of mineralogy. 

 The use of heavy liquids, for separation according to specific gravity, and of 

 magnetic separation, together with the application of these in quantitative work, 

 might have been treated in much greater detail. In this section, as well as in 

 the one on radio-active minerals, illustrations of the various types of apparatus 

 would have been useful. No mention is made of microscopical examination, 

 which often affords considerable information in the investigation of " alluvials," 

 and is generally a useful prelude to a chemical analysis. Although lists, showing 

 the minerals in which each element occurs, are given, the information is too scanty 

 to be of much use, since the formulae given for the minerals are reduced to very 

 simple terms, and there is little indication, either by text or typical analyses, of the 

 nature and proportions of the elements to be expected. 



The purely chemical parts of the book, however, are admirable, and should 

 prove very valuable to all chemists engaged in the examination of such materials. 

 In general several methods of determination are given for each element, together 

 with methods of separating the latter from those others likely to occur with it, as 

 well as elaborate and detailed schemes, often in tabular form, for the complete 

 analysis of the various types of minerals. The two latter should be particularly 

 useful, as several of the processes are new, while others are taken from journals 

 not always available in scientific libraries. Numerous references to the literature 

 are given, and the usual tables of "factors" appended. The letterpress is 

 excellent, and misprints are few and unimportant, the chief occurring on pages 48, 

 62, and 94. 



A. Scott. 



BOTANY AND AGRICULTURE 



Science and Fruit Growing. By the Duke of Bedford, K.G., F.R.S., and 

 Spencer Pickering, M.A., F.R.S. [Pp. xxii + 351, with 47 figures 

 and 4 plates.] (London : Macmillan & Co., Ltd., 1919. Price 12s. 6d. net.) 



The Woburn Experimental Fruit Farm, which was established in 1894, has, 

 under the direction of the authors, attained a more than national reputation. 

 Situated on the Oxford clay with an extent of not more than twenty acres, the 

 achievements have been considerable and form another monument to the debt 

 which the community owes to private enterprise. The writers have, in this, 

 continued the tradition established by their ancestors, Francis Duke of Bedford 

 and Lord Leicester, and in the pages before us present the results of a quarter 

 of a century of patient research. It is always refreshing to study unorthodox 

 views, but when those views are the outcome of carefully controlled experimenta- 

 tion the conclusion is inevitable that the orthodoxy, far from being a real outcome 

 of practical experience, is in fact the cumulative effect of mere tradition that has 



