246 H. L. FAIRCHILD PLEISTOCENE UPLIFT OF NEW YORK 



In 1902 the writer published a description of the Iroquois beaches ex- 

 tending from Richland to Watertown Center, with maps, profiles, and 

 table (114, pages 106-112). In that stretch of splendid beaches con- 

 spicuous from the Rome, Ogclensburg and Watertown Eailroad, the gravel 

 bars are spaced through considerable vertical range, up to 50 feet at 

 Watertown Center and to 77 feet at the Farr farm, 3 miles east of Water-, 

 town, the point used in the accompanying map and table. 



It has been the theory of students of the glacial lakes phenomena that 

 the differential uplift of a basin should produce splitting of the bars by 

 the relative lowering of the water level north of the fulcral line, the 

 isobasal line passing through the outlet. It was expected that the vertical 

 spacing of the Iroquois beaches would increase steadily to the northward. 

 This expectation was not realized. Prom Richland to Watertown Center, 

 28 miles by the shore, the bars exhibit no consistent or harmonious rela- 

 tion and no decided increase in vertical range, though the stretch of shore 

 is decidedly tilted as a whole. Four miles farther to the northeast the 

 range at Farrs is 77 feet. From there northward, so far as our detached 

 figures show, the vertical range of bars decreases, and toward the north 

 edge of the State the beach becomes simple. 



This discordance with our theories has been something of a puzzle ; 

 but now, in the light of the tabulation and the facts of this paper, the 

 explanation seems clear. The Richland- Watertown series of .bars registers 

 a local wavelike land uplift just before the extinction of Iroquois and 

 before any recorded rising of the land occurred at Covey outlet. During 

 the life of Iroquois the Rome outlet had been rising and the water level 

 in correspondence. Eventually the ice-body had been so long and so far 

 removed from the upper Saint Lawrence Valley and the Adirondack mass 

 that relatively rapid uplift began in the Watertown district and the land 

 uplift exceeded the rise of the water level by the amount of splitting 

 recorded in the Watertown beaches. 



The latest or extinction water level at Farrs is taken as 671 feet, after 

 much study of the matter in the field and office. The summit of the bar 

 series is 733 feet, which makes the amount of splitting of the bars, the 

 uplift out of Iroquois waters, 62 feet. The tabulation gives the glacial 

 uplift at Farrs as 69 feet. When the Covey outlet became effective the 

 rising of the Iroquois water level practically ceased, as that district was 

 not lifted until after the extinction of Iroquois. The stationary attitude 

 of the Iroquois water gave the Watertown wave of land uplift the chance 

 to slowly rise out of the waters and produce the series of beaches. 



Between Rome and Richlaud the Iroquois shore has not been mapped, 

 it lying in a drumlin area, but must be examined with reference to this 



