HISTORICAL 221 



the work of the river, cutting down through 100 feet to its present in- 

 active condition. He does not discuss the higher terraces nor the deltas 

 at the mouths of tributary valleys. 



The Geology of Vermont, 1861, gave positive adherence to the iceberg 

 theory of drift origin. New England was supposed to have been deeply 

 submerged in the ocean. Vermont had been buried 5,000 feet in the sea 

 and marine beaches were found up to a present height of 2,196 feet 

 (volume 1, page 183). Evidently the high-level glacial gravels and 

 glacial lake deposits were mistaken for marine features. The terraces 

 of the Connecticut Valley were described and figured by C. H. Hitchcock 

 with considerable detail. They were considered the product of the com- 

 bined action of the lowering sealevel (and lake) waters with that of river 

 flow. This view was essentially correct ; but the upper limit of the static 

 waters was not recognized, because of the belief in deep submergence, and 

 no discrimination was made between the terraces built in standing water 

 and those due wholly to river work. 



WORK OF JAMES D. DANA 



The earliest important writings on the terraces in the southern part of 

 the Connecticut Valley were made by James D. Dana in his Manual of 

 Geology, in the Transactions of the Connecticut Academy of Science, 

 volume 2, and chiefl}^ in the American Journal of Science. In the early 

 edition of his Manual, 1867, he recognized the depression of the land 

 during the "Champlain Epoch," with increase in height of the marine 

 plane toward the north. Elevations were given as follows : 30 to 50 feet 

 in northern Connecticut, 100 to 170 feet in Massachusetts, and 170 to 

 200 feet in New Hampshire. 



In 1873 (in American Journal of Science, volume 5, pages 198-211) 

 he expressed the view that the amount of Champlain submergence was 

 about 50 feet on Long Island Sound and greater northward, and that the 

 high valley terraces were river floodplains which ^''once filled the valley 

 across" to depth of 200 feet. In subsequent papers his estimate of the 

 amount of submergence was less for the shore of the Sound. 



Extended writings up to 1876, in volumes 9-12 of the Journal, dis- 

 cussed the phenomena in much detail, holding the view that "the ocean 

 took no part in the formation of the river terraces" ; "the height of the 

 flood the chief cause of the height of the terraces" (volume 10, page 

 435). He thought that the river had a depth in glacial flood of 150 feet 

 and a width of 15 miles in the Hartford-Turners Falls section (page 

 507). The depression of the Connecticut coast he estimated as 15 feet. 



The publication by "Warren Upham in 1878 of detailed description of 



XVI— Bull. Gbol. Soc. Am., Vol.. 25, 1913 



