irrigation. 
not only proves highly serviceable to the 
farmer himself, but to his neighbours ; who 
tl'.us obtain a supply of hay, when their own 
meadows have failed. 
When laud has been long watered, 
its qualities are meliorated considerably , 
but this is not the work of a day ; and when 
the adjoining lands abound with coarse 
herbage, with water grasses especially, the 
crops will too frequently sufi'er by such 
vicinity. , It will, at first view, appear 
strange, but it is nevertheless true, that 
swampy lands become firmer when regular- 
ly watered. In their natural state the 
water oozes upwards, and loosens the soil , 
but after the proper levels are found, and 
the catch drains are laid, so as to draw off 
the surplus water, the moisture is drawn 
downwards, and the finer parts get into the 
insterstices, so as to compact the whole, 
and give a firm footing, where before even 
.a sheep would have been bogged. We 
must, however, state, that though some 
watered meadows will bear cattle, it is by 
no means adviseable to let any thing heavmr 
than a sheep feed upon them : the latter 
do little injury to the ridges, and by their 
close bite, as well as by their excellent 
manure, cause the grass to tiller forth, so 
as to form a close mat upon the soil. 
Whereas when large animals are allowed 
to tramp on the ridges, the, borders of the 
drains are in general injured ; and when- 
ever, as will happen, the prints of their feet 
are left, the soil will become quaggy, and 
retain little pools which infallibly sour the 
grass, and negative the intention of water- 
ing. Hence clay soils are extremely diffi- 
cult to improve by this operation ; nor can 
such be reclaimed but by a very expensive 
course of draining, manuring, and bi eaking 
into a crumbly state: certainly clay soils 
may be formed into ridges, and grass may 
be made to grow upon them ; but they will 
not produce sweet herbage ; their surfaces 
will crack, their crops will be precarious, 
and their seasons for feeding must depend 
entirely on the dryness of the weather. 
Hence we may, in general terms, consider 
clay soils to be unfit for irrigation ; the ex- 
pence being great, and the money being 
more likely to yield a greater profit by other, 
means; while their crops and pasturage 
are, in various points, of an inferior value. 
But to proceed : the secondary drain, 
whicli supplies the w'hole of a field through 
Which it passes, should be iiiteirupted at 
every fell of four inches at farthest, by 
small sluices, or penstocks, and have small 
branch-drains cut to the right and left, is 
such manner as may cause the water to 
branch out into the w'liole expanse of its le- 
vel. The turf cut from the surface of each 
drain, ought to he placed, face downwards, 
between it and the land it is to overflow ; 
being made firm and level, by beating with 
the flat of a spade. As the penstocks are 
situated just below the lines of the branch- 
drains above described, they keep up tlie 
w^ater, so ps to fill, and to cause their over- 
flowing into the next inferior talus or slope, 
as shewn in fig. 1 and 2, where A is the 
main drain, taken from the water-head or 
river, B ; the drain C, C, C, C, shews the 
secondary drain, which, being on a decli- 
vity, would carry off all the water, were it 
not kept up at the places where the catch- 
drains, or branches D, D, D, D, proceed la- 
terally from it, by the sluices E,E,E,E. 
By this means, any particular level, either 
1, 2, 3, 4, may be irrigated at pleasure, with- 
out wetting the others ; the water being 
Jiept on by the sluice above, and carried 
away by the sluice appertaining to each le- 
vel respectively. Or, if other meads at 
some distance are to be watered, the se- 
condary channel, having all its sluices open, 
will convey it to them without interruption, 
when all its sluices are opened. 
It is evident, tliat in this manner the 
whole of the water is carried down to the low- 
est level : hence, it becomes a matter of no 
small importance to ascertain, that the 
whole shall either be absorbed or ire cairied 
off; so as not to injure the last level, whicli 
might otherwise be subjected to very con- 
siderable injury, were the inundation to be 
too long supported. The judicious com- 
puter will be cautious not to allow so much 
to remain, as may rot his grass in lieu of 
causing it to vegetate vigorously. This, in 
some situations, presents a very serious diffi- 
culty ; for if the water is debarred free ac- 
cess to the lowest levels, they will be less 
fruitful than the others, which, exclusive of 
the great fecundity derived from first re- 
ceiving the fluid, receive absplutely a larger 
portion of moisture. The greatest care is 
therefore requisite, to insure that the tail, or 
spent-water, shall be carried off. Where 
the declivity is considerable, and that the 
stream, or any other water-course, offers 
itself to receive sucli tail-water, at a due le- 
vel beneath, there is no difficulty; but 
where the stre.am takes another course, and 
the descent is triflipg, some artificial means 
must be resorted to. Perhaps no more 
simple or efficacious plan can be hit upon, 
