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. There 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 



