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Analysis of the Anthracite of the Calf on Hill, Edinburgh, 

 By Dr A. JVOELCKER, Professor of Chemistry in the 

 Agricultural College, Cirencester. * 



(From the Edinburgh New Philosophical Journal for April 1850.) 



We are in possession of analyses of anthracite from seve- 

 ral localities, and we have learned by them, that the composi- 

 tion of this mineral, like that of coal, varies very much ac- 

 cording to the locality where it is found ; so that there are 

 scarcely two localities which furnish anthracite of exactly 

 the same composition. 



All samples of anthracite which have been analysed, have 

 been found to contain carbon, hydrogen, oxygen, nitrogen, 

 and more or less inorganic matter, as well as sulphur (at 

 least where it has been looked for), in a proportion which dif- 

 fers but slightly from that in which it occurs in common coal. 

 Generally speaking, the per-centage of carbon is larger in 

 anthracite than in common coal, whilst hydrogen predo- 

 minates in the latter; and we find, likewise, ^that the more 

 the anthracitic character of a sample is pronounced, the 

 greater is the deviation from the composition of common 

 coal. On the other hand, the more an anthracite resembles 

 common coal in its physical character, the closer is the ap- 

 proximation to the latter in chemical composition. The sul- 

 phur which has been found in every specimen of anthracite 

 in which it has been sought for, is generally considered as ex 

 isting in it as well as in coal, in combination with iron, as 

 iron pyrites, 'but the subjoined results shew that the sulphur 

 found in anthracite does not always occur in the form of 

 iron pyrites, but is, in part at least, in combination with 

 the organic elements of the mineral. In the following ana- 

 lyses the greatest care was tafcen to deprive the anthracite 



* Read before the Royal Society of Edinburgh, 4th March 1850. 



