LXIl. CHEMICAL NATURE OF THE SOILS OF N.S.W. 
Food is dissolved in Water.—The food received by the 
plant is nearly all absorbed in solution by means of the 
root-hairs, and there must be sufficient water to dissolve a 
part of the mineral matter of the soil. It is generally con- 
ceded that an annual rainfall of 18 inches or over is neces- 
sary for the growth of wheat. In our case, unfortunately, 
it usually happens that in the area of diminished rainfall 
the greater part of the rain falls in the first three or four 
months of the year at a time when it is of no benefit to the 
crop. Ifthe rain fell in the spring and summer months, 
a much smaller amount would be sufficient. 
Prevention of Loss of Water from Soil.—I am of the 
opinion that a good deal can be done even in the absence 
of irrigation to ameliorate the conditions of farming. There 
are large areas in the State where it is out of the question 
to establish irrigation works—at all events, for many years 
to come. It then becomes a question of conserving within 
the soil the moisture present in the soil, and though this 
is hardly an aspect of the matter that is of much interest - 
to the engineer, it is, nevertheless, a question of very great 
importance how to counteract the continual loss of water 
which evaporates from the leaves of the plants and from 
the surface of the soil. I shall, however, not discuss the 
matter at any length, but shall enumerate a few of the 
operations which will be found of benefit in conserving 
water in this way. The planting of belts of trees to break 
the force of the winds is a very important operation, since 
evaporation from both leaves and soil is greatly accelerated 
by the passage of wind over the land. Mulching of the 
surface soil, liming, thorough tillage, and a proper system 
of drainage are all operations which result in the production 
of a fine spongy texture in the soil, which increases its 
water-holding capacity and reduces the amount of surface 
evaporation. | 
