426 THE POPULAR SCIENCE MONTHLY 



Foul Point, extending into Bering Lake. 



over, in some places there is a somewhat abrupt change from a bed of 

 good coal of considerable thickness into coal of a much lower grade or 

 into carbonaceous shale. In some places the movements have resulted 

 in the coal being intimately mixed with the rocks of the roof and the 

 floor. The roof and floor are most commonly of shale. One sometimes 

 finds the roof to be of shale and the floor of sandstone, or vice versa; in 

 a few places sandstone forms both the roof and the floor. The roof is 

 frequently fractured to such an extent that in mining timbering will 

 be necessary. 



The coal of the region is of good quality, the best grade being 

 anthracite, the poorest grade semibituminous. The average of 32 

 analyses of samples of coal taken by Dr. Martin so as to represent the 

 coals of the whole field was as follows: 



Per Cent. 



Total moisture 6.02 



Volatile combustible 1 0.44 



Fixed carbon 75.30 



Ash • • • • • 8.23 



Sulphur 1-47 



The fuel ratios of these coals varied from 3.61 to 15.88, the average 

 being 7.78. The highest B.T.U. value was 15,574, the lowest 8,386 

 and the average of the 32 analyses was 13,174. The average analysis 

 of 7 of the coals which were classed as anthracite was 



Per Cent. 



Moisture 7.88 



Volatile combustible 6.15 



Fixed carbon 78.23 



Ash 7.74 



Sulphur 1-30 



