48 EXPLORATIONS, WESTERN ATLANTIC, STEAMER BACHE, 1914. 



The temperatures over the inner part of the shelf, both vertical 

 and horizontal, were extremely uniform. 



Except for its demonstration that the cold coast and abyss waters 

 were discontinuous, the temperature profile does not throw much 

 light on the movements of the water in this region; but the salinity 

 profile (fig. 49) is unusually instructive in this respect. In general, 

 sahnity, like temperature, was much lower near the coast than over 

 the oceanic basin, with the same sudden transition from one type of 

 water to the other. The distinction is even sharper in salinity than 

 in temperature, the coast water (33-35^/oo) being separated by a 



Meter 



Fig. 49.— Profile of salinity, , and density at the temperature in situ, . 



_, from the mouth of 

 Chesapeake Bay, across the continental shelf, to a point 90 miles southeast of the 200 meter contour. 



zone of much salter water some 1,000 meters thick from the abyssal 

 water (34.9-35^/oo)- On the shelf itself there was a steady rise 

 of salinity from the land out to about the 100-meter contour, the 

 curves for successive saliaities showing that the axis of freshest water 

 dipped from the surface next the land to about 30 meters at station 

 10160, overlying considerably salter bottom water. It is over the 

 200-meter contour that the profile is most instructive, for here water 

 fresher than 35^/oo suddenly dips downward like a tongue into the 

 Salter ocean water, and the bottom water of about 35.37^/oo at station 

 10260 seems to have been entirely surrounded by fresher water. 



