10-0) SOILS — FERTILIZERS. 621 



" In tlio cotton belt of the United Stiitos the rainfall lies In almost all parts 

 between 23 and 60 In. The mean annual temperature nowhere falls below 60°, 

 and the warmest month always just exceeds 80°. In the British Empire these 

 conditions are found in their entirely in parts of India and in the West Indies, 

 which are already important colton-producinji countries." Other colonies whose 

 annual rainfall lies within the specified limits and which are considered in some 

 detail with reference to their suitability for cotton growing are Uganda, Nya.sa- 

 land, Gambia, the Sudan, Nigeria, Gold Coast, Rhodesia, British East Africa, 

 the Union of South Africa, Australia, and New Guinea. 



The weather of the past agricultural year, F. J. Brodie (Jour. Roy. Agr. 

 Soc. England, 80 {1919), pp. 201-212). — The weather conditions, particularly 

 rainfall, temperature, and sunshine, in Great Britain during the winter of 

 11)18-19 and the year 1919 are briefly summarized as in previous reports. 



Swedish meteorological observations, 1917 {Met. lakttag. f^verige {Oh- 

 serv. Met. SuM.), Met. Cetitnthnist.. ,50 {1917), pp. XIV+183; 59 Bihang {1917), 

 PP- [3]-\-50, pis. 6, figs. 21). — These are the detailed reports of the Central 

 Meteorological Institute of Sweden for 1917, with an appendix containing a 

 special report on frequency of hail in Sweden, 1865-1917. 



SOILS— FERTILIZERS. 



The soil, A. D. Haix {London: John Murray, 3. ed., rev. and enl., 1920, pp. 

 XV-\-352, pis. 4, figs. 14). — This is the third revised and enlarged edition of this 

 book (E. S. R., 20, p. 1113). 



I The developments and modifications in theories relating to soils from 11 

 years' research have mat(M-ially modified and enlarged the book, particularly 

 with reference to the knowledge of .soil organisms and their functions and the 

 Btructure of clay and the soil reactions influenced by clay, as indicated by the 

 present conception of colloids. 



A student's book on soils and manures, E. .L Russell {Catnbridge [Eng- 

 land]: Univ. Press, 1919, 2. cd., rev. and enl., pp. XII-\-2JtO, figs. 45).— This is 

 the second edition of this book (E. S. R., 34, p. 716), in which the author has 

 incorporated a number of changes in the section on fertilizers and manures in 

 order to bring in new material and new points of view which have been de- 

 veloped by war-time conditions in England. 



Methods for the physical analysis of soil, P. Koettgen {Internatl. Mitt, 

 liodcnk., 7 (1917), No. 5-6, pp. 205-246). — Considerable experimental work oit 

 diiTerent mi-thods for the physical analysis of soils is reported, on the basis 

 of which the author developed a process of mechanical separation of soils into 

 groups according to grain size, chiefly by sieving, weighing, sedimentation, and 

 centrifuging. Groups of grain sizes are determined from greater than 1 mm. 

 to less than 1m. the hitter being ajiparently the most diffi'nilt. 



Mechanical and chemical analyses of part of the agronomic station at 

 La Jaille, C. T. Ai.i.der (Guadeloupe Rap. Sta. Agron., 1 (1918-19). pp. 35-37).— 

 Mechanical analyses of samples of soil from the station show a high percentage 

 of fine sand, silt, and clay. On this basis the soils of the locality are classed 

 as fine sandy clay. The subsoil is of the same mechanical composition. 



Chemical analyses show that these soils are poor in lime and other alkaline 

 materials, but contain no soluble free acids. The total contents of potash and 

 phosphoric acid are not high, and the available content approaches the minimum 

 permissible. There is a 3 per cent content of organic matter, and the nitrogen 

 content is also high. 



