BIGELOW: COAST WATER EXPLORATION OF 1913. 187 



over the seventy-five fathom curve; and there is every reason to as- 

 sume that by a run of a very few miles further to the south Gulf Stream 

 water of 35%o would have been found. Close to the shore of Long 

 Island the salinity was only about 31.2%o, with an expansion of water 

 fresher than 32.2%o olT its eastern end. And there was a second tongue 

 of comparatively low salinity abreast of Barnegat. On the other hand 

 Gulf Stream water (35%o) was encountered on the surface at the outer 

 edge of the continental slope off New Jersey, with a rise of salinity 

 from 32.4%o to 35.25%o in a distance of only twenty miles (Station 

 10070 to Station 10071). 



Close to the New Jersey coast the salinity rose, north to south, 

 from 31.2%o near New York to 32.2%o off Cape May. And the 

 importance of Delaware Bay, like that of the Connecticut and Hudson 

 Rivers, as a source of land water, was shown by the pronounced off 

 shore swing of the curve of 32.2%o abreast of its mouth. At the time 

 of our visit its influence was evident for at least fifty miles from Cape 

 May (Station 10072). The curves show a tongue of comparatively 

 salt water approaching the shore north of Delaware Bay; and a much 

 more pronounced one just south of it, where the curve of 33.5%o lies 

 only thirty miles from land, good evidence that the Delaware water 

 had but little effect either south or north of the Bay in July. The 

 approach of water of high salinity toward the coast south of New 

 York is further illustrated by the fact that off Cape Henlopen the 

 curve of 33%o was within thirty-five miles of land instead of at a dis- 

 tance of eighty miles, as was the case abreast of Long Island. And 

 while this phenomenon is in part a concomitant of the steadily decreas- 

 ing breadth of the continental shelf, the water was Salter over the 

 twenty-five fathom curve off Cape Henlopen than over the 100 

 fathom curve off Long Island. 



The freshening effect of Chesapeake Bay on the surface is unmis- 

 takable; the water fifteen miles off its mouth being the freshest 

 (29.25%o) water encountered during the cruise. And the surface salin- 

 ity was only 32.2%o over the 100 fathom curve, though 33.5%o water 

 occupied this relative position on the shelf only thirty miles further 

 north. But the water from the Bay had little effect further seaward, for 

 in the next fifteen miles the salinity rose to 33.5%o, i. e., to practically 

 the same saltness as at the same relative position off Barnegat. 



The work south of Cape Cod occupied only about three weeks time; 

 hence it is hardly to be expected that any considerable change in 

 salinity would have taken place. x\nd as a matter of fact the stations 

 on the way north show no clear evidence of any. But water samples 



