* 158 



PROFILE NO. 19— STATIONS 351-355. 



The section runs from in on the Bank west-southwesterly across the 

 southwest slope and offshore into deep water. The stations were 

 taken October 21-22. 



Salinity. — Water of 35 "/qo was found at the outer station extending 

 downward 450 meters (246 fathoms). The general shape of * its 

 northern boundary corresponded closely to water of this same char- 

 acter at the Tail on profile No. 17; and similarly a salinity of over 

 36 "/oo was found at the 125-meter (68-fathom) level, 68 miles seaward 

 of the slope, which identifies this as Gulf Stream. Water of 34.5 "/no to 

 33.5 "/oo lay on the slope and in over the bottom of the Bank, while a 

 surface fihn of water fresher than 33 "/oo spread nearly 30 miles sea- 

 ward from the edge — the largest quantit}' of water of such low sahnity 

 found in any of the sections for October. 



Temperoture. — xVgain we found a band of water colder than 0°, 

 presumably a connection with those which we had previously observed 

 on the east slope and at the Tail. It lay on the slope between the 75 

 and 120 meter (41 and 66 fathom) levels, and extended only 8 miles 

 offshore, which is a decrease in size from that around the Tail and 

 northward. The bottom water in on the Bank was 0.85°, which is 

 colder than that found on the Bank to the eastward but not so cold 

 as the water which lay in over the southwest slope and at the Tail. 



The influence of the band of icy water on the slope was reflected 

 in the temperatin-es on the surface, whjch, being colder than the 

 water on either side of it, and despite the influence of solar warmth, 

 retained its Arctic character. These two bodies of warmer water 

 separated by the cold band correspond in temperatures higher than 

 10°, but are quite dissimilar in physical character. Inshore over the 

 Bank a fresh surface layer 30 meters (16 fathoms) thick attained 

 a temperature higher than 10° through solar warming. Offshore 

 at the outer stations, on the other hand, we find water with tempera- 

 tures higher than 15°, which water can have only one som-ce, the 

 Tropics, and in this region is referred to as Gulf Stream. 



Consideration of the relativelj" high state of sidinit}' (except on the 

 surface, where diluted by water fresher than 33 "/oq) , combined with the 

 relatively high temperature of the two bodies of warm water (except 

 where the section was punctured by the icy band), suggests that this 

 locality may bound the extreme northwestern extension of frigid 

 Arctic water along the western slope of the Grand Bank. 



