On the Drainage of Land. 
325 
are better than flats of the same length with the tiles, excepting 
on running sand or very soft ground. Stone drains are various ; 
the most common here are wall and dribble, or rubble, the former 
as main, the latter as tributary. Perhaps there is none so good as 
a wall-drain, but the expense is too great for extensive use. The 
dribble is made witlh stones, broken about the size of which they 
are used for roads, the drain about 8 inches wide, filled a foot 
high with the stones, and a little straw put on them to keep the 
dirt out until it is settled down ; such drains answer a good pur- 
pose where there is a fair fall, say from 1 in 20 to 1 in 60, and 
put in properly ; that is, the stones clean, and at the depth of full 
30 inches, as the deeper they are put in the less likely they will 
be to choke from the entrance of the soil. There is another de- 
scription of stone drain I have seen, which is very good, but it 
must be naturally confined to certain districts on account of the 
description of stone required, which is a thin, slaty rock ; the 
stones I or 2 inches thick ; one stone is placed upright against the 
side of the drain, and another leant against it, thus, ^^^^^ ^ 
few small stones filled in over them, thereby forming a hollow 
drain at little expense, a waggon-load doing a chain in length. 
Clay-draining is a very good kind of draining, if done on the 
proper description of soils, and very much to be recommended 
on account of its cheapness and durability, although I am aware 
I may meet with opposition to this opinion. I have knov;n it 
partially in use about twenty years, but within the last eight or ten 
it has made considerable progress in the districts I am acquainted 
with. It was first used on pasture, which perhaps it is most suit- 
able for ; but it has answered the purpose on arable land ; it also ' 
shows the way in which drains act more clearly than most others, 
namely, that the water enters them at bottom, not at top, as is 
erroneously supposed by some. I think it was first tried by a 
celebrated mole- drainer, whose name I forget, who no doubt 
found the difficulty of getting mole-drains to stand any length 
of time, on account of portions failing and spoiling the re- 
mainder. 
Wood has been in use for draining a great number of years, 
and is still in use to a certain extent ; but, except on bogs, or soft 
ground, it cannot be used' to so good ])urpose as stone or tile; for 
after it has been in some few years, it is liable to choke up when' 
the wood is- rotten, although some may stand a number of years> 
as I have heard persons say who have dug across wood-drains 
