The number of castings on the surrounding fields was now very large.
Sept. 19th; 40 holes, 8 castings; all defaced.
Sept. 22nd; 43 holes, only a few fresh castings; all defaced.
Sept. 23rd; 44 holes, 8 castings.
Sept. 25th; 50 holes, no record of the number of castings.
Oct. 13th; 61 holes, no record of the number of castings.
After an interval of three years, Mr. Farrer, at my request, again looked
at the concrete floor, and found the worms still at work.
Knowing what great muscular power worms possess, and seeing how soft the
concrete was in many parts, I was not surprised at its having been
penetrated by their burrows; but it is a more surprising fact that the
mortar between the rough stones of the thick walls, surrounding the
rooms, was found by Mr. Farrer to have been penetrated by worms. On
August 26th, that is, five days after the ruins had been exposed, he
observed four open burrows on the broken summit of the eastern wall (W in
Fig. 8); and, on September 15th, other burrows similarly situated were
seen. It should also be noted that in the perpendicular side of the
trench (which was much deeper than is represented in Fig. 8) three recent
burrows were seen, which ran obliquely far down beneath the base of the
old wall.
We thus see that many worms lived beneath the floor and the walls of the
atrium at the time when the excavations were made; and that they
afterwards almost daily brought up earth to the surface from a
considerable depth. There is not the slightest reason to doubt that
worms have acted in this manner ever since the period when the concrete
was sufficiently decayed to allow them to penetrate it; and even before
that period they would have lived beneath the floor, as soon as it became
pervious to rain, so that the soil beneath was kept damp. The floor and
the walls must therefore have been continually undermined; and fine earth
must have been heaped on them during many centuries, perhaps for a
thousand years. If the burrows beneath the floor and walls, which it is
probable were formerly as numerous as they now are, had not collapsed in
83