1823.] Mr. Farey on procuring Fresh Water in the Sea. Sand. 
tures to be’ hazarded, and several 
learned essays to be written, until at 
length some one explained its pheno- 
Mena as above; and the same has 
more recently happened at Bridling- 
ton, in Yorkshire. Around Eneland, 
the cases are very numerous of wells 
affected, as to the heicht of their fresh 
water, by the tide; although ia many 
instances the facts may have escaped 
- notice, and in more instances haye 
never been published. © 
I have hitherto heen considering the 
cases of holes or wells left to them- 
selves, and not affected _by the lading 
or drawing of water from them; and 
here I would remark, that with very 
copious springs, passing either through 
the open gravel of a valley, or the free 
fissures of a rock, the ordinary draw- 
ing of water could occasion little 
difference in the circumstances; but, 
if ever the drawing of fresh water 
from a hole or well, thus situated, 
near to and interruptedly connected 
with the sea, exceeds for any conside- 
rable time the quantity of land-supply, 
and the surface of water in the hole or 
well is thereby lowered below the sea- 
level at the time, from that instant the 
supply will in part be drawn from to- 
wards the sea; and, accordingly as its 
water is near or. far off, horizontally, 
* and as the artificial depression of the 
water is greater or less, and the fis- 
sures more or less open next the sea, 
will the time be which will elapse be- 
fore first brackish, and at length salt, 
water will begin to enter the hole or 
well; where, but for this inordinate or 
long-continued drawing of water, no 
saltness would ever have been per- 
ceived, 
_ I have already intimated, that the 
superficial parts of the sand of the 
beach, even opposite to the mouth of a 
valley, producing a good spring, will 
in most cases become saturated with 
brackish or salt water on the rising of 
the tide; because of its water, being 
nearest at hand, to first fill the inter- 
stices, then become empty, through 
soaking away and by evaporation, 
during the ebb; and this circumstance, 
as well as lessening the risk of atany 
time drawing the water in a hole, 
lower than the sea is at the time, 
makes it advisable, whenever practica- 
ble, to sink the hole intended to water 
a ship, above or more inland than the 
high-water line. 
In the cases I have alluded to, at 
the ond a page 202, wherein it may be 
39 
necessary for the mariner to sink his 
hole on the naked beach, below high- 
water line; it would, for avoiding or 
lessening the soakage of the super- 
ficial brackish water above mentioned. 
into the hole, perkaps be advisable to 
shovel off and throw away the super- 
ficia} sand, as deep as it may be found 
cuarged with salt water, for a consi- 
derable space around the intended 
hole. 
A tall cask or pipe, whose bottom 
and lower parts on the side next the 
Jand, are pierced with numerous small 
gimlet-holes, should in such case be 
set in the hole, and the sand fiiled in 
around it; and, to guard against being 
surprised by the rising of the tide, 
before the watering can be com- 
pleted, especially where the spring 
appears a weak one, it would be right 
to sink two or three of these perfo- 
rated casks, as far distant irom each 
other as conveniently may be: so that, 
by lading or drawing slowly from each 
at the same time, the lowering of the 
surface of the water in each may be as 
little as possible; whereby the risk of 
drawing either brackish or turbid 
water into them would most likely be 
prevented. 
It may not be amiss to mention 
here, that several. wells have been 
sunk for domestic purposes near to the 
sea, which at first, and for atime, 
yielded good fresh water on a level 
with the sea, but which wells have 
come by degrees to afford water which> 
is brackish and bad: the reason of 
these failures has been two-fold : first, 
the wells have been sunk of too con- 
tracted dimensions, so that sufficieut 
reservoirs of water are not held in their 
bottoms to answer the sudden periodi- 
cal demands; or else, second, due 
care has not been observed (espe- 
cially after dry seasons, when the 
springs are diminished) in drawing or 
pumping only such quantities at a time 
as the spring supplied: but the well 
has, on the contrary, been frequently 
and much lowered, or perhaps emp- 
tied of its water ; and owing to which, 
the salt water has been able to pene- 
trate from the sea, and perhaps irre- 
trievably to saturate the strata around 
the well; where, but for such injudi- 
cious Management, a perpetual satura- 
tion of fresh water might, for ever, 
have prevented the access of salt 
water. Every weil in the situation 
alluded to, should be furnished with a 
float (those of stone are the maples 
an 
