280 
Chemical Analyses . 
[Sept, 
rosion of the platina capsule upon which the incineration was to be effected. Copi. 
ous fumes of sulphur, and of a white oxyde were given off, and a crust wm 
formed on the platina, which proved to be an alloy of bismuth and lead. 
The sulphu rets expelled amounted to 10 per cent.; the residue after burning 
was 52, so that the carbon in this specimen, apparently so well adapted for mak- 
ing pencils, was less than 40 per cent. ! Its specific gravity was so high as 3.16, 
the cause of which was explained by the presence of the metals. 
The graphite of the Himmalaya has been fully described by Doctor Abel and 
by Captain Herbert, as to its external characters. From its low specific gravity 
(2.27) I was led to suppose that it would prove more pure than the crude Cey- 
lon mineral, and this opinion was confirmed on submitting a portion to the same 
treatment : The results of a rough analysis gave. 
Carbon, 716 
hon. 5.0 
SiJ ex, 15.0 
Alumina, &c g 4 
100.0 
Another opportunity of making a comparison with English graphite was 
afforded me by the arrival of a supply of finely pounded “ black lead,” for the use 
of the Calcutta Mint, purporting to he of superior quality. Here again however 
I was disappointed, for an analysis of 100 grains yielded the following results : 
Hygrometric moisture expelled from the powde, . . 2.7 
Carbon burnt off with difficulty, 53.4 
Iron taken up by acid, 79 
Earthy impurities, 36 0 
100.0 
There is so far satisfaction in finding the English specimens deficient in purity 
to such an extent, that it inclines us to a more favorable opinion of the Ceylon 
and Himmalayan varieties, and proves that they may be applied to all the pur- 
poses at least for which the former are imported into India. 
The Ceylon graphite has only been known commercially four or five years : the 
Government had shipped small quantities of it to England by way of trial, audit 
answered so well that they were induced to receive it, amongst other articles, in lieu 
of revenue at a fixed valuation, when they were suddenly surprised at the quantity 
of this novel currency offered in payment ! A large heap was thus accumulated, and 
as the island abounds with the mineral, and there are no padlocks upon the mines, 
as m Cumberland, it might soon effectually destroy the income of the Borrowdale 
company, if introduced largely into the English market. The natives of Ceylon 
make no use of it It might be well worth while to import some into Calcutta for 
ddlv T r iCa ! USeS ’ n °' V that the ^cation of machinery is increasing 
a ly. Some ot the picked fibres ground between two smooth surfaces of glass 
landT IU ‘rTi 116 Sl ‘? hteSt SCratCh ’ vvhereas the pounded black-lead from Eng- 
land immediately scratched the glass, and was audibly gritty under friction. 
5. Varieties of Indian Coal. 
vecZTT ,° f analyS i 8 ’ With rCSpect to ‘he specimens of Coal, was merely di- 
and of L "^~ oa ** Percentage of the aqueous and volatile matter, 
specimen ''Tf' 6 7 T* * the ‘"opoct.on of coke or carbon in «ch 
i cunien was deduced from the loss in burning- 
