169 
Details of Borings in Search of Fresh W iter. 
92—119 Blue clay, yellow and white clays, blue and white, and white and yellow 
clays, all hard, with kunkur. 
120—1274 YelloW clay and sand, yellow sand, and fine yellow sand with a little 
clay; hard : here the auger was partly broken ; the edges were found sharp- 
ened like a knife. 
Remarks. The water at 66 feet appeared tasteless, probably owing to the heavy rams 
this season, in March, which had made the water in all the wells tolerable. The sub- 
stance brought up with the auger from the greatest depth, 125 1 feet, effervesced 
with acids, and the water was well tasted. After repeated trials, failed to penetrate 
or to break off a piece of the rock so as to bring it to-day* 
N. B. It is not mentioned that the water rose in the auger hole ; but the upper 
strata in this boring had fallen in several times, and this might have prevented the 
rise of the water. 
5. Section, the satne us that published in the 12 tk Vol. As. Res. from 1 9th May, 1804, to 
15 th January, 1815- 
Feet inclusive. 
0 to 21 Earth, rubbish, sandy blue clays. 
22 — 57 Blue clays, rotten and charred wood, latterly mixed with kunkur, and 
stiff. 
58 — 65 Very stiff bluish, greenish, and yellow clay, with kunkur. 
66 —122 Stiff variegated clays, blue, reddish, yellow, lead coloured, &c. with sand 
and kunkur. 
123 —141 Coarse greenish yellow sand, dark grey sand, red and grey, and dark grey 
sand, with a little talc (mica ?) 
Remarks. The greatest depth attained was on the 11 July 1814, when the borer first 
broke. All subsequent attempts were ineffectual, the rods breaking before the depth 
of 140 feet had been regained; and ultimately, a part of the rods was left sticking as 
supposed in the rock. On the 15th July 1814 , the water rose to near the surface of the 
ground, and was good and plentiful, but from the heavy rains at the time it was 
doubtful whether the rise wins to be attributed to springs below. In the subsequent 
attempts, the auger came up dry, from the lowest hard stratum. From the wells first 
alluded to being all brackish, and from these borings, I think it may be concluded, that 
there are no springs but of salt water likely to be met with in the vicinity of Calcutta 
within 75 or 8(1 feet of the surface ; and from the borings Nos. 2 and 3 it appears 
evident that there are fresh water springs at a depth not exceeding 130 feet, and that 
their source is of sufficient height to allow them to rise within 4 or 5 feet of the sur- 
face of the most elevated lands on the banks of the Hfigli. 
It of course matters not at what distance the source of these springs may be from 
Calcutta, so long as it he of sufficient height, and that they are prevented from rising 
hy a continued bed of impervious clay. 
This must he the case, or the fresh waters would have risen and combined with the 
springs in the salt strata, and have been rendered incapable of rising higher than the 
sources of the latter ; hut it appears by the borings, that the former rose 14 or 15 
feet above them, and it is not improbable that they would have risen still more had 
they been secured from obstructions from the falling in of the upper strata by a 
cylinder of wood or metal. 
Experience has shown, at home, that the springs obtained in this manner always 
afford an abundant supply of water ; and many of the largest manufactories, in and 
about London, are now furnished with all the water they require from pipes, which 
We been sunk hy boring, from 200 to 500 feet. 
The expense in England attending the operations of boring and lining the aper- 
ture with metal, appears now to be very inconsiderable ; the over-flowing well in the 
Gardens of the Horticultural Society at Chiswick cost only 130 £ ; and the borings 
were carried down 329 feet, before springs were met with that rose sufficiently to 
give an over-flowing "fountain. In Cambridge, where the practice for boring for 
water is now common, and the usual depth of boring required is about 130 feet, the 
cost of obtaining a fountain that affords from 11 to 12 gallons of water a minute is 
only 25 £. 
I am, &c. 
A. N, 
