BIGELOW: COAST WATER EXPLORATION OF 1913. 231 
been a similar, but more pronounced off shore current opposite Chesa- 
peake Bay, much as it is represented on the current chart of the North 
Atlantic (Soley, 1911), and surface density suggests that the fresh 
water from the Bay spreads out, fan-like, to the north, as well as over 
the heavier ocean water. The salter water which alternates with 
these comparatively fresh tongues is in part a contrast phenomenon; 
but the salinity curves immediately south of Delaware Bay can only 
be explained as due to an actual shoreward drift of water of high 
salinity (p. 187). And the current data at Station 10074 suggest, 
though they do not prove, that this salt tongue was swinging, eddy-like, 
toward the southwest. Just north of Delaware Bay, there seems to 
have been a similar eddy-like movement which, added to the southerly 
flow of coast water, produced the strong southwest current which was 
found at Station 10072. Surface salinities, like the current measure- 
ments at Station 10064 suggest traces of a northerly movement, or 
“banking up”. of the ocean water south of Long Island, a process 
which had progressed so far by the end of August as to raise the surface 
salinity from about 32.8% (Station 10062) to about 34% (Station 
10112). 
Surface density, being practically the same off Cape Cod as over 
the outer part of the continental shelf south of Nantucket, does not 
indicate any general flow across Nantucket Shoals into the Gulf of 
Maine in July, or vice versa; nor does surface salinity afford any un- 
mistakable evidence of a dominant current in that region, though the 
eurve of 33% suggests a possible southeasterly drift. Salinities show 
that there must have been an indraught of ocean water into the 
eastern side of the Gulf, which is consistent with the fact that the 
| surface density of the northern and eastern parts of the Gulf was very 
, much higher than that of the ocean water outside George’s. Bank. 
| To compensate for this tongue of ocean water, there was an outflow of 
| land water off Penobscot Bay; and the salinity curves suggest a 
| general southward drift of surface water along the western coast of 
the Gulf (Plate 2). 
The salinity curves, and our actual current measurements, agree 
very well with the earlier data, as summarized in the U. S. Coast Pilot 
(1912). According to the latter the prevailing drift over Nantucket 
Shoals is easterly, which agrees so well with our salinity curves as to 
make it a fair assumption that there is actually a dominant easterly 
current in this region in summer. The few current measurements 
which have yet been made on George’s Bank (U. S. Coast Pilot, 1912, 
Mitchell, 1881) indicate a similar easterly drift, veering northward 
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