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BIGELOW: EXPLORATIONS IN THE GULF OF MAINE. 95 
to disprove the supposition that this is an annual, if not a constant 
phenomenon. A similar indraught is shown by Schott, (1902) on his 
chart of the Atlantic. 
Unfortunately salinities at other times of year do not aid as to 
whether or not the 1912 conditions were normal, for there are only two 
titration records from within the Gulf, north of George’s Bank in 
Dickson’s tables, one of 32.9 off Cape Cod, April, 1896, the other of 32.3 
off Cape Sable in the same month. These are several records in his 
table from George’s Bank, and I have received two samples from its 
northern edge, collected November, 1911, with salinities of 32.7 and 
32.9 respectively. 
GENERAL CONSIDERATIONS. 
Various explanations have been proposed to account for the band 
of cold water of low salinity which bathes the coastal slope from New- 
foundland to Cape Hatteras, one of the earliest being that it is a 
branch of the Labrador Current flowing southerly along the shore. 
And although there is little actual evidence, other than low tempera- 
ture, in its support, this is the one which has found its way most gener- 
ally into literature, scientific as well as popular. Thus Libbey (1891), 
in his discussions of ocean temperatures south of Nantucket, constantly 
refers to the cold wall as the “Labrador Current.” Of late years, 
however, practical oceanographers have found less to recommend it, 
and Verrill, (1874) long ago questioned whether the low bottom tem- 
peratures which he observed off Portland in 1873 were not really a part 
of the cold bottom water of the North Atlantic rather than evidence 
of Arctic water. The facts, according to Verrill, do not warrant 
the assumption that an Arctic Current, properly so called, as dis- 
tinguished from tidal currents, enters the Gulf of Maine; but he quali- 
fies this generalization by adding that the Gulf gets constant acces- 
sions by the tides of cold water which has primarily come from the 
north. 
According to Schott, (1897) and Hautreux, (1910) the source of the 
cold water, as far south as New York, is not the Labrador Current, but 
the St. Lawrence. But Pettersson, (1907) discarding the idea of an 
Arctic Current, definitely classes the cold wall along the North Amer- 
ican coast as “an updrift of the cold bottom water of the ocean 
when pushed against the coast banks,”’ the motive force for this push 
being the “sinking cold water at Newfoundland,” though, as he points 
out, “we know too little of the hydrography of the Gulf Stream and of 
