258 ANNALS NEW YORE ACADEMY OF SCIENCES 



tance north from the decouverte and increases very rapidly toward the 

 southeast. At the bottom of the western wall, the sandstone, No. 25, 

 rises barely 5 feet above the floor of the excavation ; at 120 feet southward, 

 it is 15 and at an equal distance farther it is 25 feet above the floor. The 

 fold continues to increase; in the western wall the top of the coal is 

 reached on the sixth bench, whereas on the eastern wall the coal rises to 

 the tenth bench and the crest has not been reached. Apparently the fold 

 extends southwardly to the Firmy fault. The full extent of the disturb- 

 ance is not shown in the decouverte wall, for the folding is conspicuous 

 beyond on the way down the hill. The anticlinal evidently consists of 

 not less than three close folds in a width of not more than 350 feet. The 

 coal is removed in benches, each about 13 feet high. 



That the fold is at least double is apparent at once in the first bench ; 

 the disturbance is less on the northeasterly side and there the succession 

 is regular. The same condition is found on the second bench, where the 

 partings of No. 6 are undisturbed, though the coal has been pressed into 

 laminas, usually almost vertical to the bedding, but sometimes distinctly 

 curved. The mass, Nos. 8 to 16, being somewhat nearer to the axis, is 

 more affected, some portions being finely polished. On the third bench 

 the coals on the easterly side are often polished like a mirror. On the 

 westerly side the coal is cut off by a fold in the shales, but farther on both 

 coal and shales reappear. This coal comes up thick from the second 

 bench, but in the folding it was cut out by the conglomerate, which comes 

 down from the fourth bench. 



In this fourth bench the conglomerate describes two petty folds and 

 then turns almost vertically alongside of the coal. Though folded with 

 the coal, the conglomerate is not conformable with it, for almost 20 feet 

 of the coal is missing. The relations seem to suggest that when the con- 

 glomerate was deposited, the coal was torn away ; indeed, one is almost 

 justified in conceiving that here is cut the course of a streamlet loaded 

 with pebbles, for at a few feet from the abrupt change in dip, conglomer- 

 ate is seen resting on the edges of the coal and shale. Above the con- 

 glomerate is a mass of more or less argillaceous, crossbedded rock, Nos. 

 2, 3 and 4 of the overlying section, apparently much thicker than in the 

 eastern wall, for it reaches to the top of the fifth bench. In crossing the 

 axis here, two folds are seen, but the coal is still quite regular on the 

 easterly side. 



On the fifth bench, on the westerly side, the shaly beds of the conglom- 

 erate seem to follow the folding of the underlying conglomerate, but ex- 

 posures on the bench above indicate that the apparently increased thick- 

 ness is due to a squeeze and that the more yielding rock has been pressed 



