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 ascertained not long ago by the foundations
having been found; and the place is now marked by stones let into the
ground. Where the abbey formerly stood, there now extends a smooth
grass-covered surface, which resembles in all respects the rest of the
field. The guardian, a very old man, said the surface had never been
levelled in his time. In the year 1853, the Duke of Buccleuch had three
holes dug in the turf within a few yards of one another, at the western
end of the nave; and the old tesselated pavement of the abbey was thus
discovered. These holes were afterwards surrounded by brickwork, and
protected by trap-doors, so that the pavement might be readily inspected
and preserved. When my son William examined the place on January 5,
85