WEDNESDAY, JUNE 24—AFTERNOON SESSION. 
The Fertility of Soils in the Tropics. 
Chairman: Str SypNney Oxivier, K.C.M.G., Permanent Secre- 
tary to the Board of Agriculture, formerly Governor of 
Jamaica, 
THE following papers were read :— 
SOME NOTES ON CERTAIN POINTS IN RELATION TO THE 
PROBLEM OF SOIL FERTILITY IN THE TROPICS. 
By H. A. Tempany, B.Sc., F.I.C., F.C.S., 
Superintendent of Agriculture, Leeward Islands. 
[ ABsTRACT. ] 
In this paper attention is directed to the importance which 
biological factors have assumed in relation to considerations of 
soil fertility. It is pointed out that up to the present time 
the results available have been arrived at under temperate con- 
ditions; activities of this description are, however, limited in 
temperate latitudes by temperature range; the intervention 
each year of a winter period, during which biological activities 
in the soil are very greatly reduced if not entirely suspended, 
constitutes a limiting factor of great importance, which is 
absent under tropical conditions. In the latter case the pre- 
valence almost continuously of a set of conditions peculiarly 
favourable to biological development causes such factors to 
assume a greatly enhanced degree of importance. 
In the course of the paper data are given showing the tem- 
perature range occurring in soils in the Leeward Islands 
Colony, which illustrate the points alluded to above, the tem- 
ete never falling below 20° C. and very rarely exceeding 
30° C. 
Summarized data are also given showing the rate at which 
organic matter tends to disappear as the result of bacterial 
action in soils under these conditions, the amounts lost varying 
