r78 



Ni:W YORK 8 TAT 10 MI SKUM 



race level along the river west of W est Chazy at the same eleva- 

 tion. In ea stern Altona at the same level rather gravelly ridges 

 are found at two or three points which resemble beaches. On 

 the road west from Sciota to Altona village, similar ridges appear 

 at 480, 540 and 580 feet, built up on the sandstone ledges of the 

 Flat rocks, all beach-shaped but with much coarse and not w r ell 

 rounded material. At 500 feet is an interesting little gravel bar, 

 like a spit, now cut through by a small stream. These Altona 

 ridges have considerable resemblance to those in Beekmantown 

 already described and may perhaps also be referable to lateral 

 stream action along a Champlain valley ice tongue, but their per- 

 sistence at about the same level, and the correspondence of this 

 with the delta level in the Saranac valley, seem to indicate 

 strongly static water action. It need not necessarily mark a 

 marine level, as there are fresh-water levels above the marine 

 ;hore lines in the region, but, on the other hand, the night reached 

 by the marine levels on Mt Royal at Montreal would seem to 

 imply a marine level along Lake Champlain at least as high as 

 this. 



These shore lines in the Champlain valley rise in level when fol- 

 lowed northward, showing that they have been tipped since they 

 were formed, but, till they shall have been more carefully fol- 

 lowed and identified along the full length of the valley, uncer- 

 tainty must prevail in respect to the amount of canting. 



The Flat rocks 



The Flat rock district in Altona is a most impressive region. 

 The naked ledges of horizontal sandstone, rising slowly in a series 

 of gigantic steps with wide tread and low rise, are extremely 

 striking. That the ice could have melted away from the region 

 so rapidly as to leave no deposit here is not to be thought of. 

 Deposit evidently was left and has since been removed. 8ome 

 four years ago G. K. Gilbert, who had recently returned from a 

 short visit to the region, suggested in conversation that here was 

 the route of a spillway. As the ice retreated away from the 

 northern foothills of the Adirondack region, the waters of the 



