84 GEOLOGICAL FEATURES OF SINGAPORE, 
of Bengal, although 1 believe the Dutch has been honorably pro¬ 
minent within the scope of their authority and rule. 
Singapore Island consists of a number of low hills and ridges with 
narrow and rather swampy flats intervening. In several places the 
sea face is elevated, but the greater portion of the circumference is 
fringed by a pretty deep belt of mangrove forest. 
With the exception of Bukit Timah, which is a granite forma¬ 
tion, the whole Island, as far as I have been able to discover, is 
composed of sandstones. Bukit Timah has an elevation of about 
530 feet. It lies to the westward and is removed about 2| miles 
from the centre of the Island. If this mass of granite was forced 
upward through the overlying strata of sandstone, they would natu¬ 
rally be foundrfeclining against it. But I was not able to discover 
this result of internal action 
If there be no inclined strata of this description, the sandstones 
may have been deposited subsequently to the eruption of the gra¬ 
nite, and then been heaved up into their present inclined position. 
The soil overlying this granite is rather a meagre one, owing, I 
suppose, to this rock being neither very porphyritic nor micaceous, 
— differing in these respects, from the granite of Prince of Wales’ 
Island. Its quartz and felspar are pretty closely blended, and on 
this account it is less liable to decomposition than the granite of 
the latter Island. Generally, the felspar and quartz, where not be¬ 
ing decomposed, are both either white or of a lightish grey colour, 
and the mica, which is rather abundant, is black and lameller. 
In several places on the ascent of the hill, this rock has the ap¬ 
pearance of being stratified,—and perhaps - it may be in, or approx- 
mating to, that transition state which may exist betwixt the new 
granite, and its cognate primary rocks, gneiss and sienite. 
Where this appearence of stratification was observed by me, the 
rock was very compact and of a greenish colour, and occasionally 
approached to quartz rock, 
I examined this granite of Bukit Timah carefully, although not 
^ chemically, and found it to contain 18 per cent of Silica or quartz 
— the remainder, according to the common average existing in gra¬ 
nite, may perhaps be taken at 62 of felspar and 50 of mica, 
