132 SCIENCE IN AFRICA 



congress of soil scientists at Oxford, and subsequently, a pro- 

 visional map on the scale of i :2, 000,000, covering Kenya, Uganda, 

 and Tanganyika, together with a classification and description of 

 soils, has been published (Milne 1936). Large areas of the terri- 

 tories are left blank, and much of the data is regarded as essen- 

 tially preliminary; moreover, the author does not profess that the 

 work in its present form can be of much value to the practical 

 agriculturalist. Nevertheless, the publication is a most valuable 

 summary of the present state of knowledge, and will no doubt, 

 stimulate further work to fill the blanks. 



Conferences of agricultural and soil chemists from different 

 territories have done much to keep individual workers in touch 

 with one another and with general advances in the science. The 

 first for East Africa was held at Amani in 1932 and a second at 

 Zanzibar in 1934 (Conference, East Africa, 1932 and 1935). At 

 these the classification and nomenclature of soils, and methods of 

 analysis were standardized. In general. East African humid soils 

 are of types which depend for their origin on local climate rather 

 than on the geological structure of underlying rocks, whereas dry 

 soils fall more readily into lithological classification. The following 

 provisional list has been adopted by all the soil chemists concerned: 

 I. Desert soils. 2. Saline soils. 3. Plains soils. 4. Black or grey 

 clays. 5. Mottled clays. 6. Red earths, non-laterised. 7. Red 

 earths, laterised. 8. Plateau soils. 9. Podsolised soils. 10. Lithologi- 

 cal types. Details of each of these major groups are given by Milne 

 (1936). This soil survey of East Africa has been considered in 

 some detail because the results provide an excellent example of 

 the type of work for which Amani exists — the correlation and 

 enlargement of results obtained by a number of workers in the 

 several East African colonies. 



In addition to the general East African soil map, certain studies 

 for the separate territories deserve notice. In Kenya some soil 

 work was done by D, S. Oracle (1930) and Mr. Beckley, the 

 present agricultural chemist, has prepared a draft soil map. For 

 Uganda there is a draft soil map prepared by Drs. Martin and 

 Griffith, and for Zanzibar and Pemba Islands one was prepared 

 by Dr. L. Raymond. In Tanganyika a special study has been 

 made of the chemistry of waters from Mount Mweru by Sturdy, 



