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than this； neither burrows nor worms were seen。
As I wished to learn how many worms lived beneath the floor of the
atriuma space of about 14 by 9 feetMr。 Farrer was so kind as to
make observations for me； during the next seven weeks； by which
time the worms in the surrounding country were in full activity；
and were working near the surface。 It is very improbable that
worms should have migrated from the adjoining field into the small
space of the atrium； after the superficial mould in which they
prefer to live； had been removed。 We may therefore conclude that
the burrows and the castings which were seen here during the
ensuing seven weeks were the work of the former inhabitants of the
space。 I will now give a few extracts from Mr。 Farrer's notes。
Aug。 26th； 1877； that is； five days after the floor had been
cleared。 On the previous night there had been some heavy rain；
which washed the surface clean； and now the mouths of forty burrows
were counted。 Parts of the concrete were seen to be solid； and had
never been penetrated by worms； and here the rain…water lodged。
Sept。 5th。Tracks of worms； made during the previous night； could
be seen on the surface of the floor； and five or six vermiform
castings had been thrown up。 These were defaced。
Sept。 12th。During the last six days； the worms have not been
active； though many castings have been ejected in the neighbouring
fields； but on this day the earth was a little raised over the
mouths of the burrows； or castings were ejected； at ten fresh
points。 These were defaced。 It should be understood that when a
fresh burrow is spoken of； this generally means only that an old
burrow has been re…opened。 Mr。 Farrer was repeatedly struck with
the pertinacity with which the worms re…opened their old burrows；
even when no earth was ejected from them。 I have often observed
the same fact； and generally the mouths of the burrows are
protected by an accumulation of pebbles； sticks or leaves。 Mr。
Farrer likewise observed that the worms living beneath the floor of
the atrium often collected coarse grains of sand； and such little
stones as they could find； round the mouths of their burrows。
Sept。 13th； soft wet weather。 The mouths of the burrows were re…
opened； or castings were ejected； at 31 points； these were all
defaced。
Sept。 14th； 34 fresh holes or castings； all defaced。
Sept。 15th； 44 fresh holes； only 5 castings； all defaced。
Sept。 18th； 43 fresh holes； 8 castings； all defaced。
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 the
course of time in the manner formerly explained； the underlying
earth would have been riddled with passages like a sponge； and as
this was not the case； we may feel sure that they have collapsed。
The inevitable result of such collapsing during successive
centuries； will have been the slow subsidence of the floor and of
the walls； and their burial beneath the accumulated worm…castings。
The subsidence of a floor； whilst it still remains nearly
horizontal； may at first appear improbable； but the case presents
no more real difficulty than that of loose objects strewed on the
surface of a field； which； as we have seen； become buried several
inches beneath the surface in the course of a few years； though
still forming a horizontal layer parallel to the surface。 The
burial of the paved and level path on my lawn； which took place
under my own observation； is an analogous case。 Even those parts
of the concrete floor which the worms could not penetrate would
almost certainly have been undermined； and would have sunk； like
the great stones at Leith Hill Place and Stonehenge； for the soil
would have been damp beneath them。 But the rate of sinking of the
different parts would not have been quite equal； and the floor was
not quite level。 The foundations of the boundary walls lie； as
shown in the section； at a very small depth beneath the surface；
they would therefore have tended to subside at nearly the same rate
as the floor。 But this would not have occurred if the foundations
had been deep； as in the case of some other Roman ruins presently
to be described。
Finally； we may infer that a large part of the fine vegetable
mould； which covered the floor and the broken…down walls of this
villa； in some places to a thickness of 16 inches； was brought up
from below by worms。 From facts hereafter to be given there can be
no doubt that some of the finest earth thus brought up will have
been washed down the sloping surface of the field during every
heavy shower of rain。 If this had not occurred a greater amount of
mould would have accumulated over the ruins than that now present。
But beside the castings of worms and some earth brought up by
insects； and some accumulation of dust； much fine earth will have
been washed over the ruins from the upper parts of the field； since
it has been under cultivation； and from over the ruins to the lower
parts of the slope； the present thickness of the mould being the
resultant of these several agencies。
I may here append a modern instance of the sinking of a pavement；
communicated to me in 1871 by Mr。 Ramsay； Director of the
Geological Survey of England。 A passage without a roof； 7 feet in
length by 3 feet 2 inches in width； led from his house into the
garden； and was paved with slabs of Portland stone。 Several of
these slabs were 16 inches square； others larger； and some a little
smaller。 This pavement had subsided about 3 inches along the
middle of the passage； and two inches on each side； as could be
seen by the lines of cement by which the slabs had been originally
joined to the walls。 The pavement had thus become slightly concave
along the middle； but there was no subsidence at the end close to
the house。 Mr。 Ramsay could not account for this sinking； until he
observed that castings of black mould were frequently ejected along
the lines of junction between the slabs； and these castings were
regularly swept away。 The several lines of junction； including
those with the lateral walls； were altogether 39 feet 2 inches in
length。 The pavement did not present the appearance of ever having
been renewed； and the house was believed to have been built about
eighty…seven years ago。 Considering all these circumstances； Mr。
Ramsay does not doubt that the earth brought up by the worms since
the pavement was first laid down； or rather since the decay of the
mortar allowed the worms to burrow through it； and therefore within
a much shorter time than the eighty…seven years； has sufficed to
cause the sinking of the pavement to the above amount； except close
to the house； where the ground beneath would have been kept nearly
dry。
Beaulieu Abbey； Hampshire。This abbey was destroyed by Henry
VIII。； and there now remains only a portion of the southern aisle…
wall。 It is believed that the king had most of the stones carried
away for building a castle； and it is certain that they have been
removed。 The positions of the nave and transepts were ascert