256 
On Draining. 
turned-up soil well exposed to the atmosphere ; such change of 
texture in the mass below is doubtless slower than in the super- 
ficial soil, but it is equally certain to occur. 
Perhaps no more striking illustration of the great importance 
of securing free ingress to air and free egress to water in the mass 
of the soil can be given than that which is derived from the fact 
that by allowing land to rest without cropping it — in short, by 
fallowing it — fertility is renewed, and this effect is produced 
solely by supplies furnished from the inexhaustible magazine of 
the atmosphere. The atmosphere is our cheapest, it is a bound- 
less storehouse of manure : then why not let it freely and deeply 
into our soil ? The earnestness with which I appeal to the 
landed proprietary of Britain to drain more deeply and abandon 
the ofttimes abortive and at all times incomplete system of shallow 
drains, is derived from the indications of experience ; and to those 
well informed of the superior economy and efficiency of the deeper 
system, it is painful to behold the sums of money daily buried in 
the soil witli such good intentions, but with comparatively so little 
useful effect. In respect, however, of the depth at which drains 
may, with a certainty of action, be placed in a soil, I pretend to 
assign no rule : for there cannot, in my opinion, be a more crude 
or mistaken idea than that one rule of depth is applicable with 
equal efficiency to soils of nil kinds : the same remark applies in 
regard to assigning any common rule of distance between drains, 
which may be greater or less according to the depth of the drains, 
and the texture of the particular soil. It must be self-evident 
that water will flow through a gravel, or a sand or a loam, with 
less obstruction to its passage than through a clay, and easier 
through one clay than through another containing different pro- 
portions of silica and alumina. There are also many other pro- 
perties of soil to which the drainer has to pay attention in deter- 
mining depth and distance, such as tightness or compactness, 
uniformity, or intermixture of soils of a different texture in the 
line of his drains in the same field, &c. &c. All these circum- 
stances will affect both his practice and the cost of the work. It 
consists with my own practice at the present time, that drains are 
being executed at depths of from 4 to 6 feet deep, according to 
soil and outfall, and at distances varying from 20 to 60 feet ; 
complete efficiency being the end studied, and the proof of such 
efficiency being that, after a due period given for bringing about 
drainage action in soils unused to it, the water should not stand 
higher, or much higher, in a hole dug in the middle between a 
pair of drains than the level of those drains. 
The cost of drainage is in like manner affected by the texture 
of soils, their stonyness, &c. ; and rates of work are being paid, 
varying from 3f/. to even Is. Of/, per rod (5 J yards), causing the 
