TAB. L. 



C A R B O ox ygenizatus. 

 Oxygenized Carbon. 



oome of the Swansea coals resemble the Denbigh coals 

 in their structure, and are nearly the same in quality. 



This upper figure has the charcoaly and stratified part in 

 various directions. Some parts resemble burnt straw in re- 

 gular rows : others form conical appearances, converging 

 or diverging from a centre. We also find horizontal and 

 oblique strata. The shining part is in various directions, 

 with a confused and shattered appearance. Some of the 

 striated parts were slightly covered with charcoal in fine 

 dust, easily rubbed off, the striated impression still remain- 

 ing in immediate contact with the shining part. In other 

 parts were thick layers of charcoal in irregular strata, but 

 somewhat horizontal to the other parts, the whole having a 

 peculiar, yet confused, appearance. It is very brittle, and 

 easily shattered to pieces. 



The lower piece is much tougher, and the striae have not 

 a vestige of charcoal about them, nor will they soil the 

 fingers. .This seems altogether more indurated. These two 

 and the Denbigh coal have nearly the same qualities as to 

 their uses. They are difficult to ignite, and burn without 

 flame, remaining a long while, and giving a great heat, 

 without much apparent change ; whence they have been de- 

 nominated Stone Coal. They are used for malting, and for 

 burning lime, and are frequently mixed with such coals 



