324 JESSE E. HYDE 
organic mud formed a few feet beyond where the edge of the sand 
had taken its new stand. The only exception to this statement is 
found in two adjacent beds which seem to have been formed 
simultaneously. 
The coal deposits, although limited in cross-section, all have a 
lineal extent which is obliquely across the railroad cut and roughly 
parallel to the strike of the inclined beds of sandstone. This is so 
persistent that crests, troughs, sharp flexures, or even an unusually 
prominent split in a seam, features which may be only a few inches 
or two or three feet at most in width, can be recognized on both 
walls of the cut, and in the same succession. These are so regu- 
larly persistent that if the sandstones could be entirely removed 
over a wide area, the shale crests would appear as a series of roughly 
parallel ridges. The directions of ten of these features, selected 
because of their prominence, have been measured and all trend 
from northwest to southeast, although they vary through 4o°. 
This directly supports the idea that they were accumulated along 
the edge of the sandstones as they advanced, delta-like, from the 
southwest. 
There is but one feature for which no explanation is offered and 
which is not wholly in accord with the interpretation. In every 
case, there were sands accumulating immediately adjacent to the 
coal deposits and simultaneously on the side away from the source 
of the inclined sands. They are never thick and always have 
extended only a few feet beyond the deposit of coal mud. These 
muds were interfingered into them. What may be their signifi- 
cance, if any, is not known. 
SUMMARY OF THE KNOWN FEATURES OF THE OCCURRENCE 
To summarize the formation of the coal: It appears that it was 
not formed as a continuous deposit and subsequently cut up by 
erosion, nor were the pockets formed simultaneously in their present 
separated condition. It appears that the pockets were formed 
successively one after the other at the edge of the accumulating 
mass of inclined sand; that the vegetable mud accumulated to a 
thickness commonly of three or five feet (possibly 40 feet in the 
case of the 35-inch coal, although this seems excessive); that these 
