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NEW YORK STATE MUSEUM 



but if they were not at the sea level of the time, formed a stage of 

 the glacial lake in which a discharge was found past the northern 

 border of the Green mountains into the lower St Lawrence valley 

 past the edge of the ice sheet. This is a point however which is 

 still under investigation. 



In the lower margin of this delta at Freydensburg's mills at 

 an elevation of 340 feet marine shells have been found. There are 

 slight topographic evidences that this portion of the deposit is 

 separated constructionally from the broad plain at Morrisonville. 

 Certainly this part of the deposit was made in the sea. The 

 calculated hight of the upper marine limit at this locality is 

 375 feet. 



Shore lines of the Mooers quadrangle. The shore lines and 

 deltas of this area are more fully described in the special report 

 on that atlas sheet. 



Beginning on the south near West Beekmantown, there are 

 faint traces of wave action up to nearly 640 feet. Occasionally 

 stronger traces with definite beach ridges are found at higher 

 elevations northward till Cobblestone hill, northwest of West 

 Chazy [see pi. 22] is reached when remarkably strong wave action 

 is found as high as 675 feet [see station 50, pl.28]. Thence north- 

 ward beach ridges occur along the northern and eastern margin 

 of the Altona flat rock district at a slightly increasing elevation 

 toward the north. There is a delta at Altona [see station 51, 

 pl.28] with what appears to be an ice-free margin at 640 feet, and 

 the remnants of another on the north branch of the Big Chazy river 

 at an elevation of at least 660 feet [see station 52, pl.28]. North 

 of Deer pond there are faint shore traces at about 705 feet. At 

 Cannon Corners on either side of the English river there are hook- 

 like bars curving into the valley mouth between 700 and 720 feet in 

 elevation. Somewhat south of these and on the extreme western 

 border of the area what appear to be wave-heaped materials 

 occur as high as 750 feet. In the extreme northwestern corner 

 of the quadrangle at the head of Kellas brook in the region known 

 as Armstrong's Bush there is a cobblestone ridge with a recurved 

 hook at its southern end at an elevation of 720 feet [see station 53, 

 pl.28] . A short distance west of this last example at the corner of 

 the road leading to Covey -Hill postoffiee and beyond the limits of 



