338 Glacial Phenomena of Canada. 



Wales ; whereas nothing has been removed, except a portion of the* 

 drift by the torrent that now flows in the bottom* (see fig. 4). 



Probable equivalency of the Drift of the Hudson Valley with 

 that of Lake Champlain and of Montreal. — I have now a few 

 remarks to offer on a part of the drift itself. South of Albany 

 the Hudson flows through a broad valley full of minor undulations, 

 between the Catskill and the Green Mountains. On the banks of 

 the river are extensive beds of sandy clay, from which the bricks 

 are made of which Albany is built. The city stands on this clay- 

 which extends far down the river towards New York, and north- 

 ward into the Valley of the Mohawk, and as I shall show, probably 

 also into the valley of Lake Champlain. Beyond the river-bank 

 it stretches E. and W. on the undulating ground towards the 

 mountains, rising, six miles in the direction of the Held erberg, far 

 above the level of the river. At its edge, Mr. Hall pointed out to 

 me that the sands, gravels, and boulder-clay of the ordinary drift 

 pass under it. The superficial deposits of the valley of the Hudson 

 therefore, consists of two subdivisions: first, the older boulder- 

 beds; and, second, the laminated clay, which at Albany is a thick 

 formation, finely and evenly bedded in layers of 1 or 2 inches 

 thick, the argillo-arenaceous lamina? of which graduate into each 

 other in shades of bluish-grey, brown, and brownish-yellow, pro- 

 ducing a beautifully ribanded aspect, and giving the impression of 

 a succession of repeated alternations of tranquil depositions in still 

 water. Boulders occur in it rarely ; and the top is covered with 

 sand, which may possibly represent the uppermost sandy beds of 

 the St. Lawrence and Ottawa districts. I searched in vain for 

 fossils, both in the paper-like lamina? of clay, and in the abundant 

 concretions, resembling those of the valley of the Ottawa which 

 contain the fossil fish Mallotus villosus. 



The Hudson runs nearly straight north and south ; and forty 

 miles above Albany, at Sandy Hill, the Champlain Canal joins the 

 river to Lake Champlain, which also trends north and south, and, 

 separated by a low watershed, lies in what must be considered a 

 continuation of the valley of the Hudson. The lake is 90 feet 

 above the level of the sea; and on the Vermont shore, 150 feet 

 above the sea, there is a section of six feet and a half of regularly 



■m> *< ■• ■ 



* I was informed by Professor Agassiz, that in the White Mountains, 

 which rise more than 6000 feet above the sea, there are in the higher 

 regions distinct indications of ancient glaciers ; and if this be the case? 

 the same phenomena may be looked for in the mountains of Gaspe\ 



