92 J. D. Dana on the origin of some of the 



(1.) Slope antedating the elevation. — There can be no doubt 

 that part of the slope antedates the elevation. This may be true of 

 each end of the slope, that is (A) the southern part adjoining the bay, 

 and {B) the northern part. 



A. The Southern Part. — A slope in the southern part may have 

 arisen («) from the tidal curi*ents with or without the waves, aided by 

 the river floods ; [h) from the waves alone ; or (c) from increasing 

 depth in the bay outward, and decreasing supply of sand. 



(a.) From tidal currents. — Oyster Point projects toward the 

 Sound between West River and the bay, and in this exposed condi- 

 tion would in all probability have been swept by the tides in such a 

 manner that it would have failed to be built up to the water's surface 

 or to mean tide level. The eastern part of this Point for the last half 

 mile is actually half lower than the western or that bordering West riv- 

 er, owing undoubtedly to the action of the cause here mentioned ; and 

 the western sufiered also ; ibr, on the other side of West River the ter- 

 race is 24 to 24^ feet high. Grape Vine Point, a mile and a quarter 

 farther north in the bay, is another example of this effect, as observed 

 on page 72, where the facts as to its little height over its middle, and 

 the western or Mill River side, and the full height of the terrace on 

 the Quinnipiac side, are stated. Had the Point been a little narrower, 

 it might have been low all the way across, so that it would have re- 

 mained doubtful whether this low level was due to tidal currents or not. 

 But the heights on the Quinnipiac side are as great as those of the 

 middle of the New Haven plain in the same east-and-west lines, so that 

 they have nearly the normal elevation. They show, therefore, that the 

 lower part of the Point is over 20 feet below the normal level, owing 

 to the action of the great central tidal flow up the bay. Again, at 

 the corner of State and Chapel streets, along side of the channel of 

 the old East Creek, the present height is 15 feet, or about 22 feet be- 

 low the full height for the latitude ; and this influence of the sweep of 

 the tides is felt all the way nearly to an east-and-west line through 

 the corner of College and Chapel streets. 



It is quite certain, in view of these facts, that Oyster Point was 

 in no part built up to the water level. How much to allow for the defi- 

 ciency, we have not facts to determine. An allowance of 10 feet 

 could not be too great; and this would give 31 or 32 feet as the 

 height which the Point would have had, if no such cause had ope- 

 rated. 



If the surface of the plain at Oyster Point, corresponding to the 

 original water level, is to be reckoned at 30 feet above the present 



