GEOLOGICAL FEATURES OF SINGAPORE. 9.‘> 
1. v ery dark and glimmering, cemented by brown pulverulent 
day. 
2. The darkest coloured, contains a good deal of quartz as 
inay be observed by a miscroscope. 
o. Small quartz grains connected by a ferruginous clay. 
4. Hematites, reddish brown, slightly glimmering. 
5. Brown coloured, mixed with blackish and very red, with 
whitish grains of quartz. 
6. Mixtures of all these. 
This scorious ironstone has been termed latcritc bv some cn-r 
quirers, and in a lew r places it and its conglomerates a good deal 
resemble in external appearance, and partly in their internal struc¬ 
ture, the original type,—the laterite, first described by Dr. Buchanan, 
from its likeness to a brick. He found it on the Peninsula of 
India, and particularly I believe on its western coast, Malabar. 
f have seen extensive beds of it at Cannanore on that coast, 
and it there materially differs from this Singapore stone, and that 
also of a similar nature found at Malacca. The Indian la ter ite, if 
we are to be guided by that observers description, ought to be 
deemed the true one. It is much lighter and more uniform in 
colour than the Singapore or Straits kinds. It is much softer than 
these when in situ, being dug out in small blocks and shaped like 
large bricks by a knife or hatchet or even a sharp piece of wood, 
It contains, Dr. Buchanan observed, u some lime.” The quan¬ 
tity of lime will doubtless correspond to that contained in 
the felspar of the underlying granite. But it becomes equally 
hard by exposure to the w eather, it is also internally more cel¬ 
lular and reticulated. I will not pronounce positively, after the 
lapse ot many years, that the Cannanore laterite reposes in situ 
on granite, but I believe it does; and that it has been the result 
of the gradual decay of the latter. 
Dr. Buchanan, observes that the laterite appears to bo the ar- 
gilla lapidma of Wallerius, has no appearance of stratification, lies 
over granite in masses, is full of cavities and pores, contains much 
iron in the form of red and yellow ochres, can be cut with a 
trowell or large knife when in the quarry, becomes hard like brick 
by exposure, does not ever contain it is said any vegetable exuviae. 
It is called in Tamul u Stria kulla” or brick stone, but its proper 
