'Transactions of the Bombay Geographical Society, from September 1850 to June 1852. Edited by the Secretary. Volume X.' [‎173] (306/458)

H aiij^
Slde r and tk||
le ^ e * Ilelii
^ greenstoi
from the aspetl
hat a mass of s|
Opposite tlie 1
of basalt, wliidj:
aeatli the freslus
ceous near fell
iposit of the alii
ise towards tW
.titled rock
,wing itself aH-
>y the well i» [i
,n-stone re*apF l,!
!e Break-^ 1
md pres® 13 "'
ard it ^
^ mixed «P
£.A<30«H FORMATION
but as it has not here been quarried to any considerable extent, and
is much worn by the sea, no very distinct conception of its structure
can be formed.
14 ,—For a large expanse southward and westward of the Fort
the lower rock is covered over by a recent marine deposit: so far
as can be discovered from the numerous excavations that have been
made in digging wells, foundations of houses &c., the whole is
a mass of trap up to the verge of the native town. During the
month of May 1851, I examined the bottom of the wet ditch from
end to end, and found no trace of anything but green-stone. This is
visible all along the sea shore from the Apollo Pier to Nowrojee Hill
a mass of it rises to the surface at Bombay Green, and again near
Port George. A little beyond this, it has been quarried to a large
extent, the quarry now forming a tank. The reek here, as also in
the wells near the Church Gate, and so probably over this division
of the island altogether, is dark coloured, hard, brittle, and
splintery, difficult to work, and not well adapted for building
purposes. About a mile beyond the Fort Gate, the trap rises
abruptly into a picturesque eminence of some 150 feet in elevation,
called Nowrojee Hill. The Harbour face of this has long been
used as a quarry, and presents a perpendicular scarp of massy trap ris
ing in blocks of great regularity in point of form, and of any size
that may be desired : a bed of stratified rock, nearly horizontal, and
about a foot thick, afterwards to be described, traverses the face of the
precipice—a lower bed makes its appearance by the sea shore. For
a quarter of a mile or more by the line of the railway, and on to the
wood-yards, the surface descends to within a little of the sea level, and
then rises abruptly into the bold eminence called Mazagon Hill, at
taining an altitude of about 180 feet : this, so far as it appears, consists
wholly of greenstone. A little to the northward of this, the surface
for three miles or so becomes nearly flat, and at the Powder Works
consists of a mass of trap tuflfa, of a pale greenish tint, curiously in
termixed with veins of calcareous spar running through it in all direc
tions. The tuffa extends into the interior of the island, assuming a vast
diversity of forms, until cut across by the stratified rock in the flats,
which is succeeded, as already stated, by the basaltic ridge along the
shore on the west.