Worm-castings were observed on the floors of several of the rooms, in one
of which the tesselation was unusually perfect. The tesser here
consisted of little cubes of hard sandstone of about 1 inch, several of
which were loose or projected slightly above the general level. One or
occasionally two open worm-burrows were found beneath all the loose
tesser . Worms have also penetrated the old walls of these ruins. A
wall, which had just been exposed to view during the excavations then in
progress, was examined; it was built of large flints, and was 18 inches
in thickness. It appeared sound, but when the soil was removed from
beneath, the mortar in the lower part was found to be so much decayed
that the flints fell apart from their own weight. Here, in the middle of
the wall, at a depth of 29 inches beneath the old floor and of 491 2 inches
beneath the surface of the field, a living worm was found, and the mortar
was penetrated by several burrows.
A second wall was exposed to view for the first time, and an open burrow
was seen on its broken summit. By separating the flints this burrow was
traced far down in the interior of the wall; but as some of the flints
cohered firmly, the whole mass was disturbed in pulling down the wall,
and the burrow could not be traced to the bottom. The foundations of a
third wall, which appeared quite sound, lay at a depth of 4 feet beneath
one of the floors, and of course at a considerably greater depth beneath
the level of the ground. A large flint was wrenched out of the wall at
about a foot from the base, and this required much force, as the mortar
was sound; but behind the flint in the middle of the wall, the mortar was
friable, and here there were worm-burrows. Mr. Joyce and my sons were
surprised at the blackness of the mortar in this and in several other
cases, and at the presence of mould in the interior of the walls. Some
may have been placed there by the old builders instead of mortar; but we
should remember that worms line their burrows with black humus. Moreover
open spaces would almost certainly have been occasionally left between
the large irregular flints; and these spaces, we may feel sure, would be
filled up by the worms with their castings, as soon as they were able to
penetrate the wall. Rain-water, oozing down the burrows would also carry
fine dark-coloured particles into every crevice. Mr. Joyce was at first
very sceptical about the amount of work which I attributed to worms; but
he ends his notes with reference to the last-mentioned wall by saying,
This case caused me more surprise and brought more conviction to me than
any other. I should have said, and did say, that it was quite impossible
such a wall could have been penetrated by earth-worms.
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