base of the stone was buried from 1 to 2 inches beneath the general
level, and the upper surface projected about 8 inches above this level,
or about 4 inches above the sloping border of turf. After the removal of
the stone it became evident that one of its pointed ends must at first
have stood clear above the ground by some inches, but its upper surface
was now on a level with the surrounding turf. When the stone was
removed, an exact cast of its lower side, forming a shallow crateriform
hollow, was left, the inner surface of which consisted of fine black
mould, excepting where the more protuberant parts rested on the
brick-rubbish. A transverse section of this stone, together with its
bed, drawn from measurements made after it had been displaced, is here
given on a scale of 1 2 inch to a foot (Fig. 6). The turf-covered border
which sloped up to the stone, consisted of fine vegetable mould, in one
part 7 inches in thickness. This evidently consisted of worm-castings,
several of which had been recently ejected. The whole stone had sunk in
the thirty-five years, as far as I could judge, about 11 2 inch; and this
must have been due to the brick-rubbish beneath the more protuberant
parts having been undermined by worms. At this rate the upper surface of
the stone, if it had been left undisturbed, would have sunk to the
general level of the field in 247 years; but before this could have
occurred, some earth would have been washed down by heavy rain from the
castings on the raised border of turf over the upper surface of the
stone.
The second stone was larger that the one just described, viz., 67 inches
in length, 39 in breadth, and 15 in thickness. The lower surface was
nearly flat, so that the worms must soon have been compelled to eject
their castings beyond its circumference. The stone as a whole had sunk
about 2 inches into the ground. At this rate it would have required 262
years for its upper surface to have sunk to the general level of the
field. The upwardly sloping, turf-covered border round the stone was
broader than in the last case, viz., from 14 to 16 inches; and why this
should be so, I could see no reason. In most parts this border was not
so high as in the last case, viz., from 2 to 21 2 inches, but in one place
it was as much as 51 2. Its average height close to the stone was probably
about 3 inches, and it thinned out to nothing. If so, a layer of fine
earth, 15 inches in breadth and 11 2 inch in average thickness, of
sufficient length to surround the whole of the much elongated slab, must
have been brought up by the worms in chief part from beneath the stone in
the course of 35 years. This amount would be amply sufficient to account
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