Prof. Johnson'' s Report on the Bradford Coal Field. 141 



It contains of moisture, vaporized at 212°, 

 Of water, tar, &c. disengaged in coking, 

 Uncondensable gas, - - - 



Carbon, _ _ - - 



Earthy matter, . _ . 



100.0 



" The ashes are of a rather deep chocolate brown, scarcely less marked 

 in this particular than any of the red ashes of anthracite. 



" No. 7. This coal was obtained from the middle part of the bed, at 

 Mason's mine, on the head waters of Wagner's run. The coal from this 

 mine, is already in the highest repute, both for domestic consumption, and 

 for purposes of the arts. It has a specific gravity of 1.388. 

 It is composed of the following ingredients. 



Matter volatile at 390°, . - - 



Vapors condensable, _ - - 



Uncondensable gaseous matter, 

 Carbon, _ - _ - _ 



Earthy matter, _ _ - . 



100.0 



" The ashes of this coal are white, slightly inclining to buff, moderately 

 bulky. 



" No. 8. This coal is from the lower part of Mason's bed ; it possesses 

 a columnar structure, the surfaces of deposition being distinctly marked, 

 its color is deep black, surface of vertical fractures and lining. 

 Its specific gravity is 1.400. It contains of 

 Water lost at 340°, - - - 



Volatile matter expelled in coking. 

 Carbon, - - - - 



Earthy matter, 



100.01) 

 " The ashes of this coal are of a white color, rather inclining to gray, 

 and not remarkably heavy. 



" E.xperiments to detect the presence of sulphur succeeded in giving 

 faint traces of that ingredient. 



" From all the analyses of coal detailed in this Report, we have the fol- 

 lowing table of general results. 



Mean, 



67.83 



18.41 



13.76 



