($359 
Of the Manner of the making ay raifing Pond-Heads. 
TF is obvious, that if you make a dam crofs a valley or fwamp, 
where at any time after, the water runs, it will produce a pond; 
and as the bank or dam is higher at the point or center, which 
is againft the loweft ground, fo much is the pond deeper ; 
and if the hills on each fide rife fteep and quick, the water 
{topped will cover lefs ground than if they rife flow. 
Now firft, for making the bank or head, you mutt be fure it 
is tight, and that it do not few or leak, as it will certainly do, 
if it be compofed of mere earth; therefore a bed or wall of 
clay, the whole length of the bank, muft be carried up with 
good ramming, from a foot or two below the furface of the 
ground, to fuch height as you propofe the water fhall ftand. 
If you do not give the bed of clay this foundation, the water 
lying under a great weight from the depth of it, will work it- 
felf underneath, fo allow a {pit or two at leaft for it. Then, 
as you ram the clay, you muft be fure that earth be brought to — 
carry the bank up with it, or elfe the fun will fearch and crack 
it, which is of pernicious confequence ; fo when it is come to 
its full height, clofe and cover it with earth immediately, left 
the inconvenience happens. 
You muft allow three feet to the breadth of this bed of 
clay, and raife it to the height you intend the water thall ftand; 
and lay. earth three feet higher; two feet would have ferved, 
but that the allowance-of one at leaft muft be made for the 
E finking 
