94 NEW YORK STATE MUSEUM 



quartzose bed terminating the lower shales. While nearly white 

 when fresh, this rock generally weathers to a grayish yellow color 

 and often exhibits yellow iron stains. On the weathered edges 

 cross-bedding structure is well brought out. When separated from 

 the rocks below by a shaly bed, this rock generally projects from the 

 bank for a sufficient distance to form a shelter for the watchman in 

 case of a sudden shower. Where this sandstone comes down to the 

 level of the roadbed, at a projecting cusp of the clifif, it has been cut 

 through and a portion of it left between the track and the gorge. 

 In the shadow of this rock mass stands the second of the watch- 

 men's shanties which we meet with in approaching from the mouth 

 of the gorge.^ The upper quartzose bed has here a thickness of 

 7J feet. Several hundred feet south of this point, where the top of 

 this sandstone is level with the roadbed, a huge ripple, 15 feet from 

 crest to crest, and nearly 2 feet deep, is shown on the river side of 

 the track. This '' giant ripple " was described and illustrated by 

 Gilbert,^ who found other ripples of similar size in the Medina sand- 

 stone at Lockport, as well as in the quartzose sandstone near Lewis- 

 ton. 



On the surfaces of the flagging stones which are derived from 

 the Medina sandstones, ripple marks of small size are not uncom- 

 mon, and the sidewalks of Buffalo and other cities where this rock 

 is utilized, often exhibit fine examples of such rippled rock sur- 

 faces. 



In the cliff of Milk cave falls (or St Patrick's falls), which is the 

 second lateral fall below the mouth of the gorge, the upper beds 

 of the Medina formation are well shown. The concretionary layer 

 is near the level of the roadbed, and has a thickness of 3 feet. 29 

 feet above it is the base of the upper gray quartzose sandstone, 

 before reaching which we find that the red sandstone gradually 

 loses its bright color, at first being mottled, and then at times losing 

 its red color altogether, though the thin partings of shale still retain 



^This is occupied by John Garlow, on whose beat most of the " Niagara 

 crinoids " (Caryocrinus ornatus) are to be found. Specimens 

 may generally be obtained from him at a small price. 



-Bui. geol. soc. Am. 10:135-40, pi. 13, fig. 2. 



