628 CHARLES EMERSON PEET 



hall is close to 120 feet A. T., and if Higher Glacial Lake Champlain 

 at the close of its history was 120 feet above sea-level, then there 

 has been no change in level in tliis part of the outlet since that time, 

 but farther soutli, at the 160- foot divide near Fort Edward, there has 

 been an uplift of more than 40 feet. 



During Marine Champlain time the lower series of terraces was 

 made in the Champlain region from the uppermost marine level 

 down to near the present Lake Champlain levels. Since the upper- 

 most terrace of the lower series, when projected southward, falls 

 below the Fort Edward outlet level, and since marine fossils have not 

 been found south of Port Henry, where they were found at a level 

 of 140 feet and lower, it is believed that the sea did not reach south 

 as far as the Hudson Valley. It has been calculated, by projecting 

 the terrace gradient southward, that Benson Landing or Putnam 

 Station was approximately the southern limit reached by the waters 

 forming the upper terrace of the lower series. During the time in 

 which the lower series of terraces was being made, which it will be 

 convenient to refer to as " Marine" Champlain^ time, upHft was taking 

 place, greater at the north than at the south, thus producing a wider 

 range of the lower series of terraces at the north than at the south. 



EXTENDED COURSE OF POULTNEY-METTAWEE RIVER. 



While the waters of the south end of "Marine" Champlain were 

 receding northward on account of the uplift of the land, or at first on 

 account of the cutting of the outlet of Lake St. Lawrence, if "Marine" 

 Champlain includes lake terraces, and later on account of the uplift of 

 the land, the streams which had flowed into Higher Glacial Lake 

 Champlain, and which, because of the sudden fall of its water-level, had 

 extended their courses across the old lake-floor plain to the new shore, 

 finally were extending their courses across the old sea-floor to the reced- 

 ing shore. This was true of the Poultney and Mettawee Rivers, which 

 during Hudson- Champlain and Higher Glacial Lake Champlain time 

 debouched into that water body by independent mouths (see Fig. 

 25, A). On the fall of Higher Glacial Lake Champlain to "Marine" 

 Champlain they became united and with other formerly independent 



I "Marine" Champlain levels would thus include both those of the hypothetical 

 Lake St. Lawrence and the levels marked by marine fossils, which are called Marine 

 Champlain levels (without the quotation marks). 



