Topographical Features of the New Haven region. 63 



iugs. For like all New England, the Sound received vast deposits 

 of gravel and sand in the Champlain era from the depositions of the 

 great glacier ; and ever since these depositions were made, the riv- 

 ers have been carrying in detritus, each year making its large con- 

 tributions ; the estimate, therefore, that the original surface, as it 

 was before the Glacial era, had been covered by all these deposits 

 to an average depth of 50 feet, cannot be excessive. After such a 

 process tending to obliterate all depressions, especially over the north- 

 em half of the Sound which has received the most of the detritus, it is 

 certainly obvious that better defined river channels than exist are not 

 to be expected. 



But the conclusion from the existing channels above suggested has 

 at least three sources of doubt — one arising from the present action 

 of tidal currents ; a second, from outflowing under currents which oc- 

 cur at times in connection with large bays ; and a third, from the con- 

 figuration of the rocky basement beneath the mud and sand of the 

 bottom of the Sound, 



(1.) Jutting capes, especially if prolonged far out beneath the wa- 

 ter, as well as obstructing shoals or reefs, inasmuch as they narrow 

 the Sound, give increased velocity to the tidal currents passing by 

 them. This cause is sufficient to account for the large deep holes — 30 

 to 33 fathoms — opposite Norwalk, where " Eaton's Neck" on the Long 

 Island side makes a long projection into the Sound beneath its wa- 

 ters, which projection at its extremity, three miles out (and hence 

 nearly half across this part of the Sound), close along side of the deep 

 holes, is within 6 fathoms of the surface. Again, near the " Middle 

 Ground," south of the mouth of the Housatonic, or of Stratford, a 

 large shoal but 2 feet deep in one part, there are deep holes both off 

 its northern and southern extremities, the former of 20 to 21|^ fathoms 

 and the latter of 20 to 27^ fathoms; and they are in part at least an 

 obvious consequence of the tidal currents sweeping by. 



Ten miles west of the mouth of the Connecticut, the Sound com- 

 mences to narrow toward its eastern termination, its southern side 

 here bending up to the northeastward ; moreover shoals made from 

 Connecticut river detritus, contract the breadth on the north. Conse- 

 quently, here begin two depressions, and half a dozen miles east, a 

 third on the north, which three unite in one broad range of deeper 

 water, 18 to 32 fathoms in depth, that continues eastward, and finally 

 increases to 50 fathoms as the waters approach the channel, called 

 " The Race," by which they leave the Sound and enter the Atlantic. 



