5S 
DRAINING. 
low, they fliould be filled with loofe (tones to within a 
foot and a half of the furface, having a turf, grafs-fide 
downwards, next the (hones. The noxious moifture con¬ 
tained in the bog will be extracted by the drains, and 
will fubfide through the auger holes into the porous 
flrata below. If the ground is afterwards ploughed, 
care mult be taken in forming the ridges, and giving 
them a defcent towards the main drain, which will 
greatly aflift the others in difcharging heavy falls of rain. 
But before proceeding to drain this kind of Iwampy land, 
in the manner defcribed, it fliould firft be afcertained 
whether the porous flrata immediately under the bed of 
clay will receive the water when let down into it ; for 
Ihonld it be already faturated with water, it may, in- 
flead of receiving more, throw up a greater quantity to 
the furface ; and thus render the evil worfe. This may 
fotnetimes be the cafe ; for the fubftrata may contain 
water that makes no appearance on the furface at this 
place, owing to the fuperincumbent'body of clay, but 
which, being connected with fome higher fpring, may 
flow up when a vent is given to it by the anger. 
Thus would a greater quantity of water be brought to 
the furface, which, having no outlet through the cir¬ 
cumjacent bank, would render the ground much more 
wet, and might, in fome fituations, almoft form a lake, 
or pond. But if the furrounding high ground declines 
deeper or lower than the bog, although at fomediflance, 
which may ealily be afcertained by the fpirit-level, (for 
a defcription of which fee the article Level,) a drain 
may be conducted thither, which will effectually draw 
off the water, though at a greater expence. A feCtion 
of a landlocked bog of this kind is (hewn at the foot of the 
engraving, fig. 3, completely (hut in by elevated banks- 
or hills of marl or clay. A, B, C, D,E, F, reprefent the 
drains, and G, H, I, K, L, M, the auger-holes, difcharg- 
ing the water into tlie loofe ftratum below. 
It frequently happens that fprings rife in the middle 
of afield, at adiftance from any ditch or open drain into 
which the water may be difcharged ; fo that a covered 
drain brought from the neareft outlet, would pafs fo 
far through dry ground as to render the expence of 
conducting the water from the fpout, greater than the 
injury done by it. To remedy this, begin by cutting a 
drain a few yards in length, or by finking a pit into the 
porous foil immediately between the lower fide of the 
wet and dry ground ; and from that bring an upright 
drain to the upper lide of the wet ground, from which 
take a branch to both fides, along the upper lide of the 
wet, fo far as'it goes. This upper drain will cut off the 
water where it riles to the furface ; the upright drain 
will convey it to that cut along the lower fide of the wet 
ground, where the water will fubfide into the porous 
fubfoil. An eafier method may be, where the retentive 
fubftratum is not deep, firfi to cut the drain along the 
upper (ide of the wet ground,, and,, after coming to the 
ftratum in which the water flows, either to bore through 
the retentive fubftratum, or cut the drain to that depth, 
by which means the water cut off above will be let 
down into the abforbent ftratum below, and thus got 
rid of at once. 
In diftriCts where the foil is compofed of an inter¬ 
mixed variety, mod commonly fand, gravel, and clay, 
but where clay forms the moft predominant part, drain¬ 
ing is a work of much greater difficulty and expence 
than in thole where both the furface and internal ft rata 
are more regularly difpofed. In thel'e foils, where al¬ 
moft every puddle is unconnected with another, and 
feparated by intervening ridges of clay, the partial col¬ 
lections of water remain until the time of great rains, 
when they have a free iffue, as over the edges of a diih, 
and thus, overflow and furcharge the furface of the clay, 
and render it fo wet and four, that its produce becomes 
every year more fcanty, and the foil itleif more barren. 
As the intervening land-beds have no communication 
with each other, it will require as many drams'us there 
are banks in number, to extract the water from each 
of. them. From the neareft and lowed part of the field 
to be drained, a main trench Ihould be cut up to the 
higheft or moft diftant land-bank, and into this fhould 
fall other drains, fomewhut in the form of the letter Y, 
communicating with each of the other land-banks, ft) 
as to draw off the water they contain, ultimately lead¬ 
ing into the main trench, which difembogues into the 
brook below. The plan of this interefting mode of 
draining is (hewn at fig. 4, in the preceding copper-plate. 
Befides the foils correfponding to the above defcrip¬ 
tion, there are others of a fimilar nature, where each bed 
being of lefs extent, and lying more regularly together, 
their drainage might be efteCted by lefs cutting, and 
confequentiy lefs expence. Under the beds of fand and 
clay that thus lie alternately together, and almoft paral¬ 
lel to one another, is generally found a body of imper¬ 
vious clay, that keeps up the water contained in the 
fand, which continues always full, moiftening the ad¬ 
jacent clay, and, in wet feafons, running over it. As 
this main under-ftratiun of clay is feldom above four or 
five feet below the furface, a drain nuift be cut to that 
depth through the middle of the field, if it has a de¬ 
fcent from both (ides ; or, if the ground decline all to 
one lide, the drain muft be cut there, where the water 
will more eafily difcharge itfelf into it ; and, unlefs the 
field is of confiderable extent, and have more hollows 
in it, one drain will anfwer the purpofe effectually ; be- 
caufe, by crofting all the different beds that hold the 
water, it will draw it from each. The great difficulty in 
draining land of this defcription is, when the direCtion. 
of the alternate beds of clay and fand lie acrofs the de¬ 
clivity of the ground ; fo that one drain in this cafe can 
have no other effeCt than that of carrying off the water 
after it has paffed over the different flrata, and would 
here naturally ftagnate in the lowed part of the field, if 
there was no other outlet for it. Therefore, when the 
ground lies in this manner, which is often the cafe, be¬ 
sides the drain in the hollow, or middle, others muft be 
cut from it, in a (loping direction, acrofs the declivity,. 
whieh, by crofting all the different veins of fand, will 
extraCt the water from each. 
In drains of this kind, there is feldom any need for 
applying the auger, as the neceflary depth of the trench 
reaches far enough down ; and as there is no fpring for 
want of connection with higher ground, to force itfelf 
up through the auger-holes, or, if there is, it cannot, at 
fo great a depth, and below fuch a body of clay, do any 
injury to the ground above. A plan of this method is 
exhibited at fig. 5, in the engraving. 
In flat tracts of rich land, where the furface is injured 1 
by a fuperfluity of ftagnant water not proceeding from, 
fprings, their drainage becomes an objeCt of the firft im¬ 
portance, and which may, in moft cafes, be accomplifh- 
ed with very little expence. The upper foil being com¬ 
pofed of a porous ftratum, of two, three, or four, feet 
in thicknefs, and having under this a (trong retentive 
body of clay, the rain-water falling on the furface, eafily 
fubiides till it meets the clay, and there being obftruCted- 
from farther delcent, the whole open part of the foil 
(lands fo full of water, as to retard tiie progrefs of vege¬ 
tation, or greatly to injure it. To carry off this water 
requires but few drains, and thefe no deeper than juft to 
reach a few inches into the clay ; betwixt which, and 
the under part of the porous foil, the greateft quantity 
of Water will remain ftagnant, when it does not appear 
fo much on the furface. In this kind of drainage the 
auger is not employed, there being no fubterraneous wa¬ 
ter to get rid of. If the ground has a fmall defcent 
from both Tides, one drain cut through the hollow part 
of the field will effectually draw oft all the water that 
the porous foil may contain; which will be greatly faci¬ 
litated by properly forming the ridges to anfwer the de¬ 
clivity of the ground, and by deepening and clearing 
out the furrowsWith the fpade. If a field of this foil 
