94 Mr. F. Forster's Observations on the South Welsh Coal Basin. 



The most peculiar and important property possessed by this Coal is 

 the swelling or branching which takes place during combustion, and in 

 the process of coking, which is effected in heaps in the open air. This 

 appearance is altogether different from the swelling exhibited by bitu- 

 minous Coal under similar circumstances, and frequently gives the 

 Coke an arborescent appearance (hence the term " G16 spagod," or 

 Branching Coal), very materially increasing its bulk, as compared with 

 the Coal from whence it is produced. In some varieties (very well re- 

 presented by the Clyngwernon Seam, see the section,) this property 

 exerts such an effect on the Coke as to make it nearly as light and 

 porous as Wood Charcoal 5 while in others, as for instance, the Great 

 Seam at Merthyr Tydville, the Coke is much harder and more ponde- 

 rous, and admirably adapted for iron smelting. The lighter Coke, when 

 free from Sulphur, is used for the manufacturing of Tin-plate. In a 

 common grate, the more bituminous varieties of this Coal emit very little 

 smoke, though a considerable proportion of thin yellow flame ; the less 

 bituminous seams, less flame, and no smoke whatever. 



The nature of my professional engagements having caused me to 

 make a number of experiments on the heating power of this class of 

 Coals, which have led me to conclude that they possess, for the use of 

 breweries and distilleries, for the raising of steam, and more especially 

 for the purposes of steam navigation, several peculiar and important ad- 

 vantages over any other Coals which have come under luy observation. 



and Clay, being first thoroughly mixed by the bare feet of one or other of the female part 

 of the family, are moulded into balls of an oval shape, and the good housewives not unfre- 

 quently display their taste by the fanciful yfsy in vi^hich they place these balls edgewise in 

 the grate, each row being inclined at a different angle ; and, under the active influence of that 

 passion for whitewashing (which, extending from the church belfry to the pigsty, adds very 

 materially to the picturesque nature of Welsh scenery), they are not unfrequently, together 

 with the bars of the grate, whitewashed also. These balls are, as may readily be supposed, 

 difficult to ignite, but being once lighted, burn for a great length of time, and being renew- 

 ed at the top as they slowly consume, the fire is not allowed to go out, in some cases, fo^' 

 many years, such a catastrophe would indeed be regarded by a thrifty housewife as ari 

 unlucky omen ; the appearance presented by a fire of this description, with various articles 

 of linen, hung up to dry, absolutely in the chimney (for the balls, like Stone Coal, emit 

 neither smoke nor flame), is not a little singular to any one accustomed to the " bUezing 

 ingles," and " black diamonds" of the north of England. 



