170 On the Mineralogy of the Island of “Ceylon. 
found in-very good preservation: but even these stones 
have never yet been found in the matrix in which they had 
been formed. It is easy to explain why the Europeans are 
not permitted to penetrate into the interior of the country 
belonging to the king of Candy, where the high mountains 
are from which the rivers flow that furnish the precious 
gems; but eyen if access were permitted, still great difficul- 
ties stand in the way of any researches, ‘These difficulties 
principally arise from the great strength of vegetation 
through all the island. The mountains are every where co- 
yered with thick’ woods, which it is almost impossible to 
penetrate, No crevices or breaks whatever are any where 
to be seen, which may direct the mineralogist in his re- 
searches. Nevertheless, it may not be altogether impossible 
to discover some naked crevices, which, when well exa- 
mined, may lead to the discovery of the gems in their ma- 
trices. The Candians themselves, however, will never sub- 
mit to the risks‘and trouble experienced by those who work 
mines of precious stones or metals, and they content them- 
selves with raking them up at great expense in the beds of 
currents, after the rainy season. 
«? We have never seen primitive granite or any porphyry 
at Ceylon, although we penetrated tothe city of Candy, si- 
tuated nearly inthe middie of the island. The apparent base 
(i.e. so far as is visible) of the mountains is gneiss, or 
secondary granite, sometimes in layers and sometimes in 
rows, some feet thick. It sometimes contains large plates 
of mica two or three inches in diameter, and often no mica 
at all. The feld spar is often very abundant, but never in 
a state of determined crystallization. The white and milky 
quartzes are very common, and sometimes in masses of two. 
or three feet. Rock crystal is found at Candy in large and 
clear pieces ; we never found it ourselves, however, in that 
state. 
‘© The stone which covers the gneiss towards the sea- 
coast, and often several miles in the interior, is an argilla- 
ceous compound, friable, and susceptible of being diluted 
in water in a great measure ; it sometimes gives signs of ef- 
feryescence 
