Overflowing Well at Chiswick. 73 
» The last specimen is of the soil immediately above the chalk. 
' Two stones were met with in this stratum; one like those 
formerly mentioned, of which no specimen could be pre~ 
| served; the other a flint, sp. 20, at 257 feet. 
67.6 Chalk; among which many flints were scattered. Of these, 
one, sp. 21, was one foot in thickness, and so unusually 
hard’ as to occupy the workmen three days in punching 
before they could force a way through it. The water was 
found at the depth of 317 feet, in a bed of soft chalk, 
mixed with small flints; the hole was bored 12 feet among 
the water, so that the total depth of the well is 329 feet ; 
/ and it is supposed by the workmen that the last piece of 
chalk that was brought up sticking to their punch, was 
from the upper surface of a new layer of chalk in which 
there is no water. Specimen 22, is a morsel of a hard 
stone, apparently containing ore, which was brought up 
in the auger from among the chalk, at the depth of 274 
feet. Specimen 23, is of the first chalk which was found 
at 261.6 feet. -Specimen 24, is from 317 feet, when the 
first water was found; it was saturated with moisture 
when first brought up; sp. 25, is the last piece of chalk 
brought from 329 feet, and supposed by the workmen to 
be from the upper surface of a new and dry layer of chalk ; 
sp. 26, various fragments of large flints broken by the 
punch at different depths in the ground ; sp. 27, morsels 
of flint and pebbles washed out of the chalk raised from 
the water-source, and supposed not to have been broken 
in punching, but to have laid among the water in their 
present condition. In cutting a solid piece of chalk, 
which had been brought up in the auger, a morsel of flint, 
exactly like these specimens, was observed, with every 
appearance of not having been forced into its place in the 
chalk by violence. 
The principal impurity discovered in this water by the action of 
reagents is common salt, of which it contains about four grains 
and a half in the pint. When evaporated to dryness, the residue 
