lies immediately beneath the turf in old pasture-land, excepting that it
often contained small stones, too large to have passed through the bodies
of worms. But the trenches above described were dug in fields, none of
which were in pasture, and all had been long cultivated. Bearing in mind
the remarks made in reference to Silchester on the effects of
long-continued culture, combined with the action of worms in bringing up
the finer particles to the surface, the mould, as so designated by Dr.
Johnson, seems fairly well to deserve its name. Its thickness, where
there was no causeway, floor or walls beneath, was greater than has been
elsewhere observed, namely, in many places above 2 ft., and in one spot
above 3 ft. The mould was thickest on and close to the nearly level
summit of the field called Shop Leasows, and in a small adjoining
field, which, as I believe, is of nearly the same height. One side of
the former field slopes at an angle of rather above 2 , and I should have
expected that the mould, from being washed down during heavy rain, would
have been thicker in the lower than in the upper part; but this was not
the case in two out of the three trenches here dug.
In many places, where streets ran beneath the surface, or where old
buildings stood, the mould was only 8 inches in thickness; and Dr.
Johnson was surprised that in ploughing the land, the ruins had never
been struck by the plough as far as he had heard. He thinks that when
the land was first cultivated the old walls were perhaps intentionally
pulled down, and that hollow places were filled up. This may have been
the case; but if after the desertion of the city the land was left for
many centuries uncultivated, worms would have brought up enough fine
earth to have covered the ruins completely; that is if they had subsided
from having been undermined. The foundations of some of the walls, for
instance those of the portion still standing about 20 feet above the
ground, and those of the marketplace, lie at the extraordinary depth of
14 feet; but it is highly improbable that the foundations were generally
so deep. The mortar employed in the buildings must have been excellent,
for it is still in parts extremely hard. Wherever walls of any height
have been exposed to view, they are, as Dr. Johnson believes, still
perpendicular. The walls with such deep foundations cannot have been
undermined by worms, and therefore cannot have subsided, as appears to
have occurred at Abinger and Silchester. Hence it is very difficult to
account for their being now completely covered with earth; but how much
of this covering consists of vegetable mould and how much of rubble I do
not know. The market-place, with the foundations at a depth of 14 feet,
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