(with a piece of tobacco pipe at a depth of 4 inches), and this rested on
broken flint and chalk which could not have easily yielded to the
pressure or weight of the stone.
A straight rod was fixed horizontally (by the aid of a spirit-level)
across a third fallen stone, which was 7 feet 9 inches long; and the
contour of the projecting parts and of the adjoining ground, which was
not quite level, was thus ascertained, as shown in the accompanying
diagram (Fig. 7) on a scale of 1 2 inch to a foot. The turf-covered border
sloped up to the stone on one side to a height of 4 inches, and on the
opposite side to only 21 2 inches above the general level. A hole was dug
on the eastern side, and the base of the stone was here found to lie at a
depth of 4 inches beneath the general level of the ground, and of 8
inches beneath the top of the sloping turf-covered border.
* * * * *
Sufficient evidence has now been given showing that small objects left on
the surface of the land where worms abound soon get buried, and that
large stones sink slowly downwards through the same means. Every step of
the process could be followed, from the accidental deposition of a single
casting on a small object lying loose on the surface, to its being
entangled amidst the matted roots of the turf, and lastly to its being
embedded in the mould at various depths beneath the surface. When the
same field was re-examined after the interval of a few years, such
objects were found at a greater depth than before. The straightness and
regularity of the lines formed by the imbedded objects, and their
parallelism with the surface of the land, are the most striking features
of the case; for this parallelism shows how equably the worms must have
worked; the result being, however, partly the effect of the washing down
of the fresh castings by rain. The specific gravity of the objects does
not affect their rate of sinking, as could be seen by porous cinders,
burnt marl, chalk and quartz pebbles, having all sunk to the same depth
within the same time. Considering the nature of the substratum, which at
Leith Hill Place was sandy soil including many bits of rock, and at
Stonehenge, chalk-rubble with broken flints; considering, also, the
presence of the turf-covered sloping border of mould round the great
fragments of stone at both these places, their sinking does not appear to
have been sensibly aided by their weight, though this was considerable.
{147}
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