ill the principal locality of these curious objects
in our island; and they are found not only in the original spot--the
quarry of Corncockle Muir, but in another quarry at Craigs, near the
town of Dumfries. Ample collections of them have been made by Sir
William Jardine, the famed naturalist, who happens to be proprietor of
Corncockle Quarry, and by Mr Robert Harkness of Dumfries, a young
geologist, who seems destined to do not a little for the illustration
of this and kindred subjects. Meanwhile, Sir William Jardine has
published an elegant book, containing a series of drawings, in which
the slabs of Corncockle are truthfully represented.[4]
The Annandale footmarks are impressed on slabs of the New Red
Sandstone--a formation not long subsequent to the coal, and remarkable
for its comparative deficiency of fossils, as if there had been
something in its constitution unfavourable to the preservation of
animal remains. It is curious to find that, while this is the case, it
has been favourable to the preservation of what appears at first sight
a much more accidental and shadowy memorial of life--the mere
impression which an animal makes on a soft substance with its foot.
Yet such fully appears to be the fact. The sandstone slabs of
Corncockle, lying in their original place with a dip of about 33
degrees to the westward, and separating with great cleanness and
smoothness, present impressions of such liveliness, that there is no
possibility of doubt as to their being animal foot-tracks, and those
of the tortoise family. A thin layer of unctuous clay between the beds
has proved favourable to their separation; and it is upon this
intervening substance that the marks are best preserved. Slab after
slab is raised from the quarry--sometimes a foot thick, sometimes only
a few inches--and upon almost every one of them are impressions found.
What is very remarkable, the tracks or series of footprints pass,
almost without exception, in a direction from west to east, or upwards
against the dip of the strata. It is surmised that the strata were
part of a beach, inclining, however, at a much lower angle, from which
the tide receded in a westerly direction. The animals, walking down
from the land at recess of tide, passed over sand too soft to retain
the impressions they left upon it; but when they subsequently returned
to land, the beach had undergone a certain degree of hardening
sufficient to receive and retain impressions, 'though t
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