, London, 1821. It has, however, been corrected and
enlarged by recent investigators.]
The tertiary rocks which form such remarkable features in the geology of
other countries are almost unknown in Ceylon; and the "clay-slate,
Silurian, old red sandstone, carboniferous, new red sandstone, oolitic,
and cretaceous systems" have not as yet been recognised in any part of
the island.[1] Crystalline limestone in some places overlies the gneiss,
and is worked for oeconomical purposes in the mountain districts where
it occurs.[2]
[Footnote 1: Dr. Gardner.]
[Footnote 2: In the maritime provinces lime for building is obtained by
burning the coral and madrepore, which for this purpose is industriously
collected by the fishermen during the intervals when the wind is off
shore.]
Along the western coast, from Point-de-Galle to Chilaw, breccia is found
near the shores, from the agglutination of corallines and shells mixed
with sand, and the disintegrated particles of gneiss. These beds present
an appearance very closely resembling a similar rock, in which human
remains have been found imbedded, at the north-east of Guadaloupe, now
in the British Museum.[1] Incorporated with them there are minute
fragments of sapphires, rubies, and tourmaline, showing that the sand of
which the breccia is composed has been washed down by the rivers from
the mountain zone.
[Footnote 1: Dr. Gardner.]
NORTHERN PROVINCES.--_Coral Formation_.--But the principal scene of the
most recent formations is the extreme north of the island, with the
adjoining peninsula of Jaffna. Here the coral rocks abound far above
high-water mark, and extend across the island where the land has been
gradually upraised, from the eastern to the western shore. The
fortifications of Jaffna were built by the Dutch, from blocks of breccia
quarried far from the sea, and still exhibit, in their worn surface, the
outline of the shells and corallines of which they mainly consist. The
roads, in the absence of more solid substances, are metalled with the
same material; as the only other rock which occurs is a loose
description of conglomerate, similar to that at Adam's Bridge and
Manaar.
The phenomenon of the gradual upheaval of these strata is sufficiently
attested by the position in which they appear, and their altitude above
high-water mark; but, in close contiguity with them, an equally striking
evidence presents itself in the fact that, at various points of the
western
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