; 
\ 
BIGELOW: COAST WATER EXPLORATION OF 1913. 209 
peake Bay. And the considerable difference in temperature between 
the surface and the water a few fathoms down is almost as conclusive 
evidence in the same direction, because any constant accession of cold 
water from below would have made the temperature more uniform, 
vertically. 
The evidence of salinity supports that of temperature, for although 
Schott (1912) believes that the low salinity of the coast water suggests 
upwelling, a more rational explanation of this phenomenon is that it 
results from the large amount of river water which enters the sea 
between Chesapeake Bay and Newfoundland, as maintained by 
Tizard (1897). I have already pointed out (1914a), that the river 
water which enters the Gulf of Maine would be sufficient to raise 
the level of the latter half a fathom per year, were it an enclosed basin, 
evaporation being more than offset by rainfall. And even larger 
amounts of fresh water come from the rivers west and south of Cape 
Cod; e. g., the Connecticut, Hudson, Delaware, and the watershed 
draining into Chesapeake Bay. ‘There is therefore no more need to 
-eall upon upwelling to account for the low salinity of our coast water, 
than for that of the Baltic, of the Gulf of St. Lawrence, or of the 
waters off the mouths of the Niger and Amazon rivers. Furthermore, 
while upwelling would lower the salinity of the surface water below that 
of the Gulf Stream, it could not possibly reduce it to the comparatively 
fresh state of the coast water (32%p to 33%po), because the deeper lay- 
ers of the Atlantic, from which any updraught must come, are far salter 
than this (34.9% , Murray and Hjort, 1912). In short, low surface 
salinity does not indicate upwelling in this case, though it does not 
necessarily preclude the possibility that such a process might be taking 
place to a small extent. Unfortunately our salinity profiles across 
the continental shelf do not establish the upper limits of the water of 
the abyss as well as the temperature profiles, for they leave a bare 
| possibility that the fresh coast water may have been connected with 
the abyssal water of 34.9%, by a continuous zone of bottom water 
fresher than 35%po (p. 344). Butalthough the data are not absolutely 
conclusive, for want of bottom salinities at the crucial depth (75-109 
| fathoms), it is very much more probable that the bottom water at this 
| depth was salter (above 35% ), just as it was warmer (p. 164), than the 
: 
| 
} 
| water below it. And this was certainly the case south of Nantucket 
| 
in August, when the salinity of the bottom water, in sixty fathoms, was 
39.17% 9 (p. 193). If our salinity profiles are correct in this respect, 
it is impossible to reconcile them with active upwelling. Density, 
likewise, argues against the existence of an updraught of abyssal water 
