Topograijhical Features of the JVeic Haven region, 65 



which the outflowing under-currents of bays appeal' to be insiiificient 

 to account for the facts, either because the bay is not of the shape to 

 produce appreciably such an eflfect, or there is not in the currents the 

 proper accordance with the ebb in direction, that we think the facts 

 afford strong evidence in favor of a former elevation of the region — 

 an elevation probably not less than 1 50 feet. In such a case Long 

 Island would have been literally the southern border of New Eng- 

 land, and the universal glacier would have had no great basin of salt 

 water to span in order to reach what is now the Island, and deposit 

 there the boulders of Connecticut rocks, some of which, according to 

 Prof. Mather, are from 500 to 1000 tons in weight.* 



* It is difficult to explain the facts in detail with regard to the Sound without a map 

 at hand. The following observations on the subject are however here added. 



The main course of deep water through the Sound west of the meridian of Guilford 

 commences near the northern shore of the Sound, off Coscob harbor and Greenwich Cove, 

 (near the boundary between Connecticut and New Tork), and just here enter Bjram, 

 Mianus and Turn rivers. From this region it stretches eastward, passes the north point 

 of the Eaton Neck spit, leaves " Middle Ground " to the north (and consequently in this 

 part is south of the middle of the Sound), and then continues directly eastward till it 

 almost touches the north coast of Long Island (being less than a mile off) in the line of 

 Guilford. At the very end of the deep water channel the depth is 18f fathoms; just 

 east of it, the depth is only 11^, then 10 and 9 fathoms. But about 6^ miles a httle to 

 the north of east, about two from the shore of Long Island there is an oblong deep hole 

 18 to 19 fathoms in depth; and 2^ miles beyond, in the same direction, commences the 

 southern arm of the great central range of deep water which continues eastward out 

 of the Sound. The great range of deep water, seventy miles long, that commences m 

 the west near Greenwich, must, as already observed, owe something of its depth, in its 

 eastern portion at least, to its distance from the northern shore of the Sound or the 

 region of rivers and detritus ; and, again, it may have had its course determined origi- 

 nally by an east-and-west depression in the configuration of the basement rocks of the 

 Sound. Still it affords some reason for believing that it once contained the channel of 

 a great river. It begins against the north shore near Greenwich, just where three 

 streams enter the Sound, as if a continuation of their united channels. Its depth at its 

 eastern extremity, and its abrupt termination there, are reasons for inferring that it 

 once continued stiU farther east, and was probably kept open by a flow of water 

 through it. If the land were formerly higher by 150 feet, as has been supposed, the re- 

 quired conditions would have existed for making it a river course. But the query 

 comes up, where in that case would have been the discharge? Its abrupt eastern ter- 

 mination takes place right opposite the large and broad Peconic bay which divides the 

 eastern end of Long Island for a distance of nearly 20 miles, making the Island in 

 form like the profile of an alligator, with its long mouth (Peconic bay) wide open ; and 

 the interval of dry land between the Sound and this bay is hardly three miles wide. 

 Moreover, directly in the line of the depression, the land is low, and is intersected by 

 Matituck lake, and also by various channels on the Peconic side. These facts lead to 

 the supposition that this Sound stream of the Glacial era, whose tributaries included 



Trans. Connecticut Acad., Vol. II. 5 Sept., 1869. 



