1867.] HARTT — ON CARBONIFEROUS LIMESTONES. 215 



Underlying these beds are seven and one-half feet of calcareous 

 sandstone, of a light lead color, and decomposing into a soft, in- 

 coherent mass; then nine feet of compact, flaggy, light brown 

 limestone, with shaly partings, apparently without fossils ; and very 

 friable shales of a blueish tint, much decomposed at the surface, 

 and hidden by rubbish. Here we have a fault, a dislocation of about 

 six feet. Then comes a bed of red, very friable, marly, calcareous 

 sandstone, of which a thickness of about thirty feet is exposed. 

 Here the surface water has excavated a considerable gully through 

 the soft sandstone. There can be no doubt, as Dr. Dawson has 

 stated, that there is a fault here, for the beds on the other side 

 of the gully are seen dipping southward, and there is no repetition 

 of the strata. 



Continuing the section, the first bed seen on the opposite side 

 of the gully is exactly like that last described, and occupies the 

 shore ibr some sixty feet. This is overlaid by a bed of limestone, 

 flaggy, with more compact bands. In the cliff these beds have a 

 dip southward of 50 ° , but at its foot they become more nearly 

 vertical, and run out some twenty feet on the beach, with a strike 

 of E. 10° S., and an almost vertical dip, inclining, however, to 

 the south about 96 ° to 95 ° . Crossing a belt of mud on the 

 shore at low tide, we find the same beds appearing, with the same 

 strike, near the bed of the river, but their dip is reversed, and 

 they are inclined to the northward at an angle of 25 ° to 30 ° . 

 The thickness of beds just described is twenty to twenty-five feet. 



A bed of the red, marly sandstone, about thirty-five to forty feet 

 thick, next follows. It seems to be irregularly stratified, and 

 there are several green layers. This same bed, in ascending- 

 order, succeeds at low-water mark to that last mentioned. 

 Beds of limestone, with a strong southerly dip, next come, 

 occupying the cliff for a distance of sixty to seventy feet along its 

 base, whence they extend out on the shore for some twenty feet, 

 with an easterly strike and an almost vertical dip. In their line 

 of strike across a belt of mud and shingle, a few yards down the 

 beach, the same beds appear again, describing a slight curve to the 

 north on the inclined beach. Tracing them towards low-water 

 mark, they gradually change their dip towards the north, until, 

 at the bed of the river, it is about 60 ° N. Examined at the 

 base of the cliff, the limestone of these beds is of a blueish color, 

 weathering light brown, concretionary in the lower part, and with 

 a band in the middle of a beautiful oolitic structure. This lime- 



