128 STEVENSON— FORMATION OF COAL BEDS. [April i8, 



wide, could not have provided material for the coal, as, only a few 

 years earlier, reckoning time as is done in the fitudes, it had been the 

 scene of a terrific debacle, which had swept 125,000,000 cubic meters 

 of rock across it and had left the surface strewn with coarse debris. 

 It would seem as though vegetation must have appeared abruptly 

 throughout the drainage area or that the streams must have changed 

 their methods quite as abruptly, so as to devote attention to plants 

 instead of to inorganic materials. 



Aside from this, the theory seems to offer no satisfactory ex- 

 planation of the areal distribution of the coal. Even though the 

 lake had been as deep originally as conceived by Fayol, the pond 

 must have become comparatively shallow prior to formation of the 

 Grande Couche, and the bottom must have fallen off quite gently as 

 it receded from the shore line at the north. One cannot conceive, 

 after reading Fayol's description of the region, that any other con- 

 dition w^as possible. The Grande Couche is on this northern border 

 of the Pegauds area, and its present outcrop is less than a mile south 

 from the granite. The outcrop is shaped much like a spreading 

 horse-shoe, with its convexity toward the north. The bed is very 

 thick on the north side of the curve but breaks up into several beds 

 at the west, where it disappears, whereas on the east side it merely 

 thins away. Southwardly, it quickly loses thickness, breaks up and 

 within a short distance it disappears. It is confined to that portion 

 of the area where, of necessity, the water was shallow. There is 

 no evidence of any sort that the water was deep; it will not suffice 

 to assert that the presence of tree-trunks in the coal proves that 

 there was an eddy here and that therefore the water was deep ; that 

 is merely an assertion that the fundamental assumptions are true. 

 The presence of those tree-trunks in such wonderful abundance, 

 can be utilized to prove that the doctrine is defective. But that is 

 unimportant; if the conditions were as described in the fitudes, the 

 water was shallow in the area now occupied by the Grande Couche. 

 The middle bench of that coal bed is about 10 feet thick for a con- 

 siderable distance, very clean, and consists so largely of prostrate 

 tree trunks that it must represent a mass of transported vegetation 

 which could not have been less than 150 feet thick. It is so free 



