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NEW YORK STATE MUSEUM 



Further consideration of the changes of the ice front and the 

 water levels at this stage are deferred to the chapter on the 

 glacial lake which then overlay the Champlain valley [see p. 168] . 



Summary of retreat of ice in Champlain valley. Less evidence of 

 the position of the ice front from time to time is found than is 

 the case in the Hudson valley. This paucity of evidence is partly 

 due to the extensive deposits of clay and sand found up to eleva- 

 tions of 400 and in certain localities up to 700 feet along the slopes 

 or in the embayments of the Adirondacks and the Green moun- 

 tains. It is also partly due to the fact that there appears for a por- 

 tion of the retreat at least to have been a lake lying over the dis- 

 trict with conditions unfavorable to the formation of pronounced 

 frontal deposits. Certainly no clear frontal moraines have as 

 yet been traced across the Champlain valley floor. 



Small glacial lakes began to appear along the margins of the 

 ice sheet as soon as it had shrunk to the dimensions of a mass 

 merely filling the valley. In the numerous embayments on the 

 western side of the valley, local bodies of water received delta- 

 building streams from the back country. 1 The drainage of these 

 waters was southward along the ice margin as shown by the south- 

 ward building of the terrace at Street Road. 



The question is raised whether or not a local glacier entered 

 Lake Champlain at Port Henry, a point east of Mt Marcy. This 

 and other localities of aberrant striation require further study in 

 the field. 



^ee paper by Frank Taylor on Lake Adirondack in bibliography 

 appended to this report. 



