perfectly parallel with the top-sward. {136a} This parallelism and the
length of the section give interest to the case. Secondly, Mr. Dancer
states {136b} that crushed bones had been thickly strewed over a field;
and some years afterwards these were found several inches below the
surface, at a uniform depth.
The Rev. Mr. Zincke informs me that he has lately had an orchard dug to
the unusual depth of 4 feet. The upper 18 inches consisted of
dark-coloured vegetable mould, and the next 18 inches of sandy loam,
containing in the lower part many rolled pieces of sandstone, with some
bits of brick and tile, probably of Roman origin, as remains of this
period have been found close by. The sandy loam rested on an indurated
ferruginous pan of yellow clay, on the surface of which two perfect celts
were found. If, as seems probable, the celts were originally left on the
surface of the land, they have since been covered up with earth 3 feet in
thickness, all of which has probably passed through the bodies of worms,
excepting the stones which may have been scattered on the surface at
different times, together with manure or by other means. It is difficult
otherwise to understand the source of the 18 inches of sandy loam, which
differed from the overlying dark vegetable mould, after both had been
burnt, only in being of a brighter red colour, and in not being quite so
fine-grained. But on this view we must suppose that the carbon in
vegetable mould, when it lies at some little depth beneath the surface
and does not continually receive decaying vegetable matter from above,
loses its dark colour in the course of centuries; but whether this is
probable I do not know.
Worms appear to act in the same manner in New Zealand as in Europe; for
Professor J. von Haast has described {138a} a section near the coast,
consisting of mica-schist, covered by 5 or 6 feet of loess, above which
about 12 inches of vegetable soil had accumulated. Between the loess
and the mould there was a layer from 3 to 6 inches in thickness,
consisting of cores, implements, flakes, and chips, all manufactured
from hard basaltic rock. It is therefore probable that the aborigines,
at some former period, had left these objects on the surface, and that
they had afterwards been slowly covered up by the castings of worms.
Farmers in England are well aware that objects of all kinds, left on the
surface of pasture-land, after a time disappear, or, as they say, work
themselves downwards. How powdered lime, cinders, and heavy stones, can
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