1881.] ^"^y [Stevenson. 



As the important beds of this group were described in detail in the pre- 

 vious memoir, only a brief synopsis is necessary liere. No additional in- 

 formation has been obtained respecting them, for the area drained through 

 Pennington's gap by the North Fork of Powell river is wholly undeveloped, 

 and only the lower coal beds are well exposed. 



The Gannel seam consists of: 



Cannel 3' \ 



Alternating layer of coal and shale V 10" > 7' 3" 



Bituminous coal 3' 5" J 



But the bed is variable and at another locality it shows three layers of coal, 

 amounting in all to but 2 feet, distributed through 19 feet of measures. 

 The coal from the Upper Splint is of superior excellence, containing but 

 3.075 per cent, of ash and but 0.406 of sulphur ; the coal from the Lower 

 Splint seems to be of equally good quality. The Kelly seam is a variable 

 bed, which, where thickest, shows three divisions ; the upper one is slaty, 

 the lower one is a splint of fair quality, while the middle division seems to 

 be a gas coal of remarkable excellence, as it contains 38.850 of volatile 

 combustible matter, with 0.771 of sulphur and only 0.890 of ash. 



The Imboden or coking seam is by far the most important. It was first 

 traced by General J. D. Imboden, who made many prospecting pits in it to 

 determine its value. This bed varies in thickness from 6' 11" to 8' 5", and 

 everywhere yields a soft coal, which produces an excellent coke. The coal 

 contains but 1.515 of ash and only 0.594 of sulphur. 



Nos. 33 and 40 were seen only in Pennington's gap. The former is insig- 

 nificant ; the latter is badly distorted by pressure and the coal is so crushed 

 as to be useless. The whole section from No. 37 to the bottom is vertical 

 at the head of Pennington's gap. The coal bed. No. 43, has not been mined, 

 but it is exposed in the bank of the North Fork, where it shows a clay 

 parting midway. No. 46 is evidently the same with No. 44 of the section 

 on p. 91 of the previous memoir. It shows nearly 3 feet of good coal on 

 the North Fork, where some mining has been done. The coal is fat, cak- 

 ing and contains much mineral charcoal. The two beds, Nos. 49 and 51, 

 were reached only in Pennington's gap, where they are no longer exposed. 



Stone Mountain. 



The structure of this mountain has been explained in another part of 

 this memoir. The groups involved in the fold include the whole series 

 from the Clinton up, but in the mountain as it now stands, one finds only 

 the lower part of the Coal Measures, with the Quinnimont group and Lower 

 Carboniferous. Exposures are very poor in both Little and Big Stone 

 gaps, and the succession of the rocks could not be made out until Pen- 

 nington's gap was reached. There the following section of the Quinni- 

 mont group was obtained, the thicknesses being estimated : 



1. Sandstone " Bee rock, " 135' 



3. Shale 15' 



3. Sandstone 13' 



