'Transactions of the Bombay Geographical Society, from September 1850 to June 1852. Edited by the Secretary. Volume X.' [‎178] (311/458)

178
gkologt of bomb at.
Ten Feet above the Sea.—1- Sea Shells, and
and sand, loose, or cemented into a variety of open shell
limestone, three to ten feet thick, called Littoral Concrete *
2 n a Blue Clay, full of Mangrove roots—sometimes but slight-
ly, sometimes entirely, decayed—always in the position in which
they grew, and perfectly undisturbed.
3 r ,l_ Rock. Or sometimes the following :—
1. _-Littoral Concrete.
2. —Rock.
1 Blue Clay, with mangrove roots, as before.—2, Yellowish
brown clay, with concrete in the ordinary forms. I have not met
in with all these at one place complete, but have no doubt that
they are to be found in abundance.
23.—From this arrangement the following inferences are deduci-
hle 1. At the time the Mangroves grew, the blue clay must have
existed at about half tide mark, the mangrove being a salt water
littoral plant only found some way within tide mark.—2. Before the
large masses of shells and gravel could have been brought into exis-
tence, the mangrove-bearing beds must have sunk so- as to suffer the sea
to wash over them, and the shell deposits to acccumulate, and the
downward movement must have extended sufficiently far to permit the
uppermost portion of these to be occasionally at least under high
water : it is regularly stratified, and contains the heaviest and largest*
sized shells now found on our shores disseminated equally throughout;
has not the slightest appearance of sand-drift, and could in no other
way, save that explained, have come into existence.—3. It could only
have reached its present position by a subsequent upheaval, which
brought matters into pretty nearly their present position,f
♦ Near the fishing village of Sewrce, on the PareII side close by the shore, a bed broOT
rth about fifty yards in length, uncertain in extent, reposes on the littoral concret , ^
Ind bed of similar depth, formerly cultivated as garden ground, and irrigated J icli y
induits, appears. In the mass itself I have not been able to
rouging to it. On being dug through, the concrete is always found below
i upper bed of sea silt changed by cultivation. I have been unable to defermme ts ^ iu th0
id as it is possible it may have been brought there artificially, I have not notic
This will be found pretty fully adverted to in the Annual Report of the
av IB'fO. I subsequently prepared a paper on the subject, which was puDu Agiatic
dinburgh Philosophical Journal (Jameson’s,! and in the Transactions of the lie g n otbe r
>ciety ; and, a considerable additional supply of facts havmg reached me, prep ^
r the British Association. It was read at Ipswich in Jan. 185 l, and '7 lJ1 .t p „ T1 h P avals ah'*
their Transactions. Parallels to these phenomena will be found m the u P be withia
pressions which have actually occurred at Chittagong, and along the Arracan
Z than a century of the present time.
nr