AT HANGMAN'S WOOD, GRAYS. 261
been discontinued for many years, and much of the land that used
to be so dressed has now lapsed into a barren and sterile state, and
the very existence of the Boulder clay below the sand has been
forgotten.
Chalk for this purpose is obtained in two ways ; first, by open pits,
secondly, by chalk wells.
1st. Open Pits.—This way, a very ancient one, is still used
in many parts of Berks, and open pits are even used together with
chalk wells, in the same field. Chalk pits are sunk some six feet, if
used in conjunction with wells, but are much deeper if the supply is
entirely obtained from them. I am told that chalk pits are the
practice round Lambourne and Hungerford, and in many of the
fields in the latter place these pits are to be seen. The position and
number of the pits and wells is entirely regulated by the size of the
field to be chalked.
2nd. Chalk Wells.—This method would seem to be the more
modern one, perhaps only dating from the middle of the last century ;
but so far I have not been able to ascertain its exact age. Mr. Luke
Lowsley, of Hampstead Norris (Berkshire) tells me that it has only
been known in that neighbourhood during the last sixty or seventy
years.
The depth of the wells varies from 15 to 40 ft. If the chalk be
very near the surface, then 15 to 20 ft. would be the depth, but where
the chalk is covered by, say 15 ft. of Tertiaries (and where the
Tertiaries are thicker it does not seem to pay to sink the wells), then
they would be from 30 to 40 ft. The greatest thickness of Tertiaries
sunk through that I know of is 15 ft., viz., at Snelsmore Farm, three
miles north of Newbury, and half a mile north of Arlington Manor.
The section given me by the well sinker was, "Sand, then clay, then
dark sand." Bare chalk is to be found on the same occupation,
about one-sixth of a mile distant, but would have to be carted that
distance uphill, thus making it cheaper to sink the shaft on the
spot.
Chalking, as far as I have seen, is only resorted to where the chalk
is covered by a sand, clay or gravel soil. I have never seen chalking
done on the Lower Chalk, because the Lower and Middle Chalk are
generally bare of soil in the tract of country under consideration,
forming Downs; and the Tertiaries and the wash from them, with the
Clay-with-flints—the soils usually chalked—are rarely, if ever, found
away horn the Upper Chalk.