6o NEW YORK STATE MUSEUM 



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and south of the village of Hermon, which is built on a terrace of 

 the Elm creek delta. The summit shore line passes through the 

 east edge of the village, with altitude 520 to 525, the theoretic figure. 

 The extended plain lying for miles along the upper valley of Elm 

 creek, from Fairbanks Corners to Scotland School, appears to be 

 due to waters held in by rock control south of Marshville. The 

 marine delta of the Grass river is at Pyrites, on the Canton quad- 

 rangle. 



Gouverneur quadrangle. The Iroquois level appears in the south- 

 east part of the area, in the higher sand plains about Fullerville 

 Ironworks, at about 780 feet. These plains are the north part of 

 the delta of the west branch of the Oswegatchie river, which 

 extends 7 miles south to Harrisville, on the Lake Bonaparte quad- 

 rangle. The narrow waters entangled among the hills could not 

 be expected to produce distinct shore features. 



The lower plains north of P'ullerville, 700 ifeet, and those at 

 Edwards, 660, seem to have been due to pondings of the Oswe- 

 gatchie while it was cutting the rock gorges at Hyatt and Emery- 

 ville. 



The marine shore lies -diagonally across the area from the north- 

 east to the southeast corner, with altitudes of 525 down to 480 

 feet. The Oswegatchie delta begins at Hailesboro, 2 miles south- 

 east of Gouverneur, and the lower levels are the extensive plains 

 at and above Gouverneur. The delta plains are fine material, as 

 the coarse detritus had been dropped above the rock barrier. 



The Gouverneur sheet shows strikingly the singular topographic 

 character of that region, a complex of smoothed rock knobs and 

 ridges, with intervening smooth silt plains. The latter are the 

 product of the sea-level waters which rinsed the drift off of the 

 knolls and hills and spread it out evenly in the hollows. The clean- 

 cut horizontal line of contact between the silt plains and the steep 

 rock slopes is characteristic of the submarine silt plains in New 

 York and Vermont. The traveler on the Rome, Watertown and 

 Ogdensburg branch of the New York Central Railroad may see 

 this feature all the v;ay from Canton south to Keenes. Southward 

 through Antwerp the road lies above the marine plane. 



Five miles northeast of Gouverneur and 2 miles south of Rich- 

 ville, by the Cole School, is a good display of summit marine cobble 

 bars on some drift knolls. The bars are from 516 feet down. 

 Evidences of wave work on the slopes is common in this district. 



Lake Bonaparte quadrangle. The Iroquois waters passed up the 

 Oswegatchie valley as a deep embayment to Harrisville, where the 



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