— 48 — The absorptive power of a soil depends largely on the colour, and a dark soil absorbs practically all the incident energy, reflecting very little. The nature of the farm soils will be described later, but it may be stated in explanation of the high temperatures recorded that the soils are without exception very dark in colour, and that this colour is due not to humus but to the presence of ferric oxides.

Subsoil temperatures were taken during the ensuing months and are given below ; the corresponding observations on the upper layers will be recorded when considering the influence of irrigation.

Subsoil Temperatures : Dry Unirrigated Soil.

Monthly Means. Time ; 8 a.m.

Month.