54 mineralogV. 



seem but partly and very slowly to part with their carbon 

 till a much higher heat is given. 



" This distinction I have not yet found noticed in any 

 chemical or mineralogical work, but it seems to me to be 

 no bad test by which to separate the graphites from the 

 anthracites ; namely, that with nitre, at a heat a little 

 above its melting point only, the former melt and are con- 

 sumed, while the latter, deflagrate and almost explode, 

 My trials were made with graphite, from Borrowdale from 

 Cochin, and from the Himalaya, all of which, as above 

 stated, diffused themselves over the nitre and were con- 

 sumed gradually, while Newcastle coal, American anthra- 

 cite, and our present mineral deflagrate smartly. 



11 It is usually taken, on the authority of Berzelius, 

 founded on Karsten's researches, that the iron in graphite 

 is a mere fortuitous mixture ; but Beudant acutely says, 

 alluding to this, that ' when the iron is wanting we have 

 no graphite, and when this substance is found in our 

 furnaces, the proportions are sensibly the same,' i. e. about 

 S per cent, which he seems to think may be the true pro- 

 portion. I do not advert to Kir wall's experiments, which 

 were merely relating to coal, and not to coal and graphite 

 in comparison with each other. 



" In Professor Vanuxem's experiments (Phil. Mag. for 

 September 1845) the quantity of manganese and iron in 

 anthracites is stated to be from 0-2 to 7-10 per cent, and 

 the water from 190 to 0-70. In the graphites he found 

 from 1-40 to 3'60 per cent, of oxide of iron and manga- 

 nese in the pure, and 20-00 per cent, in the impure kinds ; 

 and of water from 060 to 1 23 in the pure, and 533 per 

 cent in the impure kinds. 



" It mav then be a mooted point to which of these two 

 classes of the anthracinoe our mineral belongs, but as I 

 have found nothing of the kind described before, I have 

 given it a distinguishing name to be adopted or rejected, 

 as better authorities shall determine." 



It appears to be an abundant mineral in the Provinces, 

 there being several localities where it is found in the vicin- 

 ity of both Tavoy and Maulmain. The Burmese often 

 mistake it for coal. 



