'Transactions of the Bombay Geographical Society, from September 1850 to June 1852. Edited by the Secretary. Volume X.' [‎198] (331/458)

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198
GEOLOGY OP BOMBAY.
upper or rather the middle strata, which look as if laid down in a
state of great repose ; and the cause speedily becomes apparent. J ust
to the northward of the great cut, the stratified rock has for a short
distance been peeled off by the sea, and the trap under it exposed
to view. Its surface is corrugated and furred in all directions
consisting mostly of globular or highly vesicular masses, with
every here and there pieces of semifused strata, showing clearly
that the sediment had assumed its position when the melted matter
impinged on it from beneath, the trap itself becoming greatly affected
in its external character by the cold material with which it came in
contact, while the sedimentary deposit was partially fused or cliertiiied
by the fiery mass. The stratified rock re-appears again all around the
end of Worlee Hill, facing the sluices, and presents itself for a few
scores of yards both along the high road and seashore, to the north
ward, where it is once more lost under the basalt. Here, however, the
stratified cliff is about six feet in height—the rock has been melted
both above and below, showing that the trap from beneath, and that
above, were both hot when they impinged on it. It has at one point been
much disturbed by some agency An office of the East India Company and, later, of the British Raj, headed by an agent. coming into operation after the fused
beds had become rigid, and which thus forced the zigzag fragments
of chertified rock into the middle of the mass. The fossils in this bed
were first discovered by Dr. Leith in 1846, when the engineering
operations were in progress, as referred to by Mr Clark. Just as I
had nearly completed the preparation of this paper, an essay on the
Geology of Bombay was read before the Bombay Branch of the Boyal
Assiatic Society, (December 11 , 1851,) by Dr H. J. Carter, from
which I take the following extract:
“ The author stated that the Island of Bombay, though unpromising in aspect
geologically, was nevertheless of extreme interest in this respect. That although
at nrsfc sight it might appear to be nothing more than a mass of black trap, y 6 *
that nevertheless it presented in its composition the three classes of rooks, via-,
Igneous, Lacustrine, and Marine.
“ there was distinct evidence of successive effusions of the Igneous rocks,
and that they had been thrown up through the lacustrine strata, which were of
ancient date, and had thus again been brought to the earth’s surface and exposed
in uiam °
, deposits ot fresh water, there could hardly be any u
eft, since to the authors knowledge no marine fossil had been found in them,"
they abounded in lacustnne ones. Dr. Leith had discovered in them two »p<
t re ^f 'f 68 > e on ® ln £ ^ 16 Cbelonian and Batraebi an orders ; the former cob
Vgf ; re t 8h water tortoises, of which he had found specimens of nine or too
dmduals bearing the distinguishing marks of the Pleuroderal JSiodiaus or Mi
,, , n dtlis IM*
1,111 ’ • -’Diirt:
^ L anim^:
^granulated
A '3
L 81
Ufti» M
01 ,IU .
^ No P« 8 ;
I, utliw ‘°
itiliesfl strata the
[irtliog else but t
tliat these
Jjl in tlie positior
{latitude Md iongiti
ititbyno means f<
a, since tlie author 1
it of Arabia’ that
Won and depress
"Itoto the Lacu
i 1 Conglomerate
sl bi altered by ii
li iron, The pres
iltlielieterogeneou:
Hlfflude it closely
Aone Series, also
11110 parts, mottled
"Sing cliaract
•to be one and th
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7 s at the northe
' ''"ing the co
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