Mr. Richardson on the Composition of Coal. 407 



although from the external characters belonging to this species of coal called splint, it ap- 

 pears that the chemical composition varies considerably. 



II. Variety. — Cannel Coal. 



1. Specimen from Lancashii e. 



This specimen comes from Wigan, where it has for a long time been worked. From its 

 capability of polish it is made into toys, &c. 



Its colour its greyish black. The lustre is highly glistening. Fracture is large con- 

 choidal. It is not so hard as the splint coal, and is sectile. Specific gravity 1-319. 

 The ashes determined in the usual way gave — 



I. -1706 grm. coal left as residue -0043 grm. 

 II. T825 grm. coal left as residue -0047 grm. 



•3531 -0090 



This amounts to 2-548 per cent. 



Burnt in the usual way with chromate of lead. 



I. -2937 grm. coal gave '890 grm. co 2 . and "1563 grm. h 2 o. 

 II. -3178 grm. coal gave -962 grm. co L „ and -1624 grm. h 2 o. 

 III. -2829 grm. coal gave -8545 grm. co 2 . and -1432 grm, h 2 o. 

 or in 100 parts 



I. II. III. 



Carbon, 83-789 83-698 83-808 



Hydrogen, — 5-677 5-643 



Azote and oxygen, — 8-077 8-001 



Ashes, 2-548 2-548 2548 



100-000 100-000 



The relation of the carbon to the hydrogen in this coal is as 1-207 : 1-000 or 6 : 5. 



2. Specimen from Edinburgh. 



This coal is called in Scotland Parrot coal, because its particles, when heated, fly off 

 from one another with a crackling noise. It occurs in many of the series in the Edinburgh 

 coal field. It easily splits, and throughout its substance several well-defined impressions 

 of stigmaria ficoides are found. Colour is black, with grey; lustre approaches that of 

 glistening; fracture is imperfect conchoidal ; sectile and frangible; specific gravity 1318. 

 The determination of the ashes gave — 



I. -2007 grm. coal left as residue, -0295 grm. 

 II. -1858 grm. coal left as residue, -0268 grm. 



•3865 * 0563 



This amounts to 14-566 per cent. 



