14), which
sloped from north to south at an angle of 30 degrees 40 seconds,
that the mould on the upper side is only six inches and on the
lower side nine inches in thickness. But this mould lies on a mass
(25.5 inches in thickness on the upper side) "of dark brown mould,"
as described by Mr. Joyce, "thickly interspersed with small pebbles
and bits of tiles, which present a corroded or worn appearance.
The state of this dark-coloured earth is like that of a field which
has long been ploughed, for the earth thus becomes intermingled
with stones and fragments of all kinds which have been much exposed
to the weather. If during the course of many centuries this grass
meadow and the other now cultivated fields have been at times
ploughed, and at other times left as pasture, the nature of the
ground in the above section is rendered intelligible. For worms
will continually have brought up fine earth from below, which will
have been stirred up by the plough whenever the land was
cultivated. But after a time a greater thickness of fine earth
will thus have been accumulated than could be reached by the
plough; and a bed like the 25.5-inch mass, in Fig. 14, will have
been formed beneath the superficial mould, which latter will have
been brought to the surface within more recent times, and have been
well sifted by the worms.
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