ANCIENT WATER LEVELS OF CHAM PLAIN— HUDSON VALLEYS 243 



Champlain was below sea level though the sea was as yet ex- 

 cluded by the ice. The region about Fort Edward was above sea 

 level as will be noted from the next feature in the sequence of 

 events. 



From some cause which can only be at present postulated from 

 the known conditions of the time and hence probably the effect 

 of the powerful discharge of the drainage through the Hudson 

 gorge, coming not only from the melting ice in the Champlain 

 district but as well as from the intake from Lake Iroquois which 

 was now in existence on the west of the Adirondacks, the waters 

 of Lake Albany were drained off. That this withdrawal was due 

 to a deepening of the Hudson gorge on the south rather than to 

 a change in the attitude of the land is indicated by the fact that 

 the shore lines of the Champlain district show no signs of a dis- 

 turbance at this time. With the withdrawal of the waters over 

 the Albany district, a divide partly of glacial materials and 

 partly of the bed rock was revealed between the nascent glacial 

 lake over the Fort Edward basin and in Lake Champlain valley 

 and the region on the south, and waters began to spill over this 

 barrier west and south of Schuylerville across those fields which 

 were later the scene of Burgoyne's defeat. Thus Lake Vermont 

 was born, consisting, on the south of the mountainous ridges 

 between two of which Lake George lies, of a shallow lake over 

 the Fort Edward district, and a constantly enlarging body of 

 water on the north, Lake Vermont proper. 



The discharge at this spillway is believed soon to have cleared 

 out and shifted into an older channel which forms a now partly 

 abandoned river valley just west of Schuylerville. The stream at 

 this stage entered the Hudson gorge at Coveville with a fall over 

 the Hudson slates at that point. At this time the Hudson gorge 

 proper from Coveville northward to Northumberland must still 

 have been filled with glacial gravels and the clays which may 

 still be seen on the valley sides. 



Thus was formed the Coveville stage of Lake Vermont. The 

 water level was now about 100 feet lower than in the previous 

 initial stage, and if the correlation worked out in this report 

 is correct, the lake was at this time about 200 feet above the 

 then sea level. The floor of the Hudson gorge at Coveville was 



