L~ 
Mineralogy and Geology. 131 
cluding Sinkep and Linga, the only two islands of the Johore Archipel- 
ago where it is now sought for, is probably above 40,000 piculs. e 
produce for many years past has ranged between that cae and 
(6000 tons), and may be expected to increase steadily. 
Seeing that tin is procured in all parts of the peninsula where it is 
sought for, and, in proportion to the enterprise and labor which are de- 
voted to the search, we may consider the entire zone as a great maga- 
zine of tin. It is, in fact, incomparably the greatest on the globe. 
hore might have seemed to offer an exception to the apparent universal- 
tt 
¥ 
and for many years having been got in considerable quantity in Malacca, 
had not afforded the strongest presumption that its want of inhabitants 
Bgtich yl om “ ih 1845, } ee an integral part of ha and 
having the same geology as the rest of the country, produced about 450 
: vig 
rations were commenced. — In 1846 above 1400 sealant were pete ed, 
the greater part from 39 pits in one valley. In 1847 the produce ap- 
pears to have been from 4000 to 5000 piculs. In 1848 it will probably 
rise to between 5000 and 7000 piculs, for the government tithe upon it 
for the year has been rented for the unprecedented sum of 8190 Sp. 
dollars ; the revenue from this source pits been, in the two preceding 
the peninsula has escaped — vant fining enterprise of private European 
capitalists, than the fact, that in the Island of Singapore, where'we have 
a line of junction between plutonic and sedimentary rocks, of above 20 
peed in length, where tin was found in former years in at least two lo- 
whete the same iron ore, with which it is associated in 
sembling sand, varying from fine to coarse, and may anes be consid- 
ered stream ore. Large specimens are found with the ore, adhering to, 
and partially invested with, quartz. We are not aware that it has ever 
been actually seen in the solid rock in the pee but in Banca it is 
found associated with iron ore in veins in the granite. A Dutch writer 
also describes whole layers as occurring in some spay A, which con- 
sist partly of granite, but in the centre principally of layers of sandstone 
and quartz, in which iron ore also appears. In the more purely granitic 
mountains, it seems to have been observed in quartz at the junction of 
the granite, with the iron-veined sandstone strata. In the Isthmus of 
Kré, it has also been found at the junction of sandstone and granite. In 
Cornwall, it appears to be dependent on granite. 
sd 
