1 Awe., 1901.] QUEENSLAND AGRICULTURAL JOURNAL. 179 
of the superfluous moisture, is what is known as draining it. It is one of the 
most important operations in the process of improving the soil and rendering 
it fit to receive seeds and to yield a crop. Drainage is a very scientific iperenes 
as you will find out by-and-bye. But you can well understand the simple 
explanation I shall here give you of how draining is done, and of the benefits 
the soil derives from the work. 
To get rid of the water it must be collected into some channel first by 
which it may be led away into a creek, lagoon, or swamp lying lower than the 
field we wish to drain. “But one channel would not collect all the water from 
a hundred-acre paddock, consequently there must be more than one. How 
many, will depend upon the nature of the soil? Let us see what soils most require 
draining? First, there are low places and swamps on some farms. Then there 
are others full of great “ melon” holes such as you often see on rick black soil. 
Tn such places you will notice that pools of water are formed after rain, and the 
water lies there so long that you begin to wonder when it is going to sink out 
of sight. But when you have discovered that beneath the rich “black soil there 
lies a stiff yellow clay, you at once see that the only way in which the water 
can escape is by the help of the hot sun and of strong dry winds. The drying 
up of the water by these means is called evapori ation, from the Latin word 
‘yapor”—steam. You have no doubt held a wet handkerchief to the tire to dry 
it. What happened? You could sce little clouds of steam rising from the 
handkerchief. The water was being evaporated, and when no more steam rose, 
then the handkerchief was dry, because all the water in it had been turned into 
steam (which is lighter than air) and had flown away to join other masses of 
evaporated avarers By and by, when great quantities of this steam are 
collected in the air, they become vi isible and form what you call clouds, and 
by and by all the water falls to the earth again in the shape of rain. There is 
no new rain anywhere in the world.. The water evaporated to-day from the 
soil of your farm travels away to somebody else’s farm, perhaps hundreds of 
miles away, where it again falls to the earth. Now, we have once more got 
away from the subject of drains, but you have at least learned whence the 
water comes which you want to remove from the land. 
Besides the swampy lands there are sandy soils, through which the water 
sinks out of sight, but if you dig through some of these soils, you will find that 
the water is only hiding—it has not left the land. Why ? Because at a depth 
of 1, 2, or 3 feet, it found our old enemy, the yellow clay, through which it 
could not pass. So there it remained, getting stagnant, and rendering the 
soil cold and wet, and only waiting for the roots of the plants to reach it in 
order to sicken them and at last kill them. So you see that a sandy soil with 
a clay subsoil is one that must be drained. 
Then there are soils consisting largely of clay. Through such soils the 
rainwater passes very slowly, and when they are clogged with wet it is impossible 
to plough them ; and on the other hand, when dry weather continues for any 
length of time, the surface is baked into a hard crust bythe sun and wind. 
Then the roots cannot spread or go down into the soil in search of food. The 
plants consequently sicken and die. But when such land as this is dr ained, 16 
becomes very valuable, as most crops will thrive in it, once the water is enabled 
to get away, and when it has been deeply ploughed, manured, and rendered 
soft and loose. ; 
Sometimes a spring of water is found on some portion of a field. I have 
seen paddocks in Queensland where there were as many as a dozen springs, all 
bubbling over, and rendering the whole of the land unfit for cultivation. 
Where ‘only one such spring occurs, it is easy to carry away the water by 
leading it into one channel, but when there are many, several channels are 
required in order to collect the whole of the water’ and prevent it from 
spreading over the land. 
In our next lesson I will explain to you what drainage does for the soil 
besides drying it. 
meagan 
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