Haupt. ] 32 [Dec. 16, 
and builds the bars in front of Barnegat, Absecon and other 
inlets, crowding the channels over against the southern shores 
of these inlets, which are thus eroded by the ebb currents. 
The same physical features will be found to result from the 
components acting north and sonth from a point near Green 
Run Inlet, Md., on the coast between Cape Charles and Hen- 
lopen. 
The tidal observations in this bay are indicated on the map 
(Plate ITT) and confirm this theory. The mean rise of the tide 
at Cape Charles is only 2.5 feet, because of the relief afforded by 
the bay. At Cold Spring Inlet it is 44, and at New York 
entrance 4.8. Here it attains its maximum height and thence 
diminishes eastwardly to Nantucket. From the secondary 
point of reversion near Barnegat on the New Jersey coast, the 
littoral currents are indicated by the heights of the tides. 
Thus at Barnegat they are 2 feet, at Absecon 3.9, at Cold 
Spring 4.4, ete. 
The interference of the tidal waves and the great difference 
of three (3) hoursin the time of high water which is compressed 
in the short space between Martha’s Vineyard and Monomoy, 
is too extended a subject to be included in this paper, which 
is intended merely for the alluvial coast line south of Long 
Island. Its consideration is therefore omitted, but the mean 
tides are recorded in part of the northern bay to illustrate the 
continuance of the concentration of the tidal energy and pro- 
gression as previously observed. 
These same laws and phenomena are found to exist on the 
Pacific Coast and will explain many of the effects which 
have only been casually noted by mariners. The phenomena 
are identical with those already described. The laws are of 
general application. 
