no 



Tlic most iiui)()rtant ])<)int. besides the fai-t that iiortheni -water 

 ■was hathiiiir the eastern e(l<i:e ol" the Hank, was the relativel,y hi^li 

 teiui)eratiu"es of this mass. Tiie hitter part of March when the first 

 records of the subsurface were secured, it was soon noted that the 

 aictic water was markedly warmer tiian normal, and yet the tem- 

 l)ei atui-es secured alon<r the east side of the Bank April 24-30 indi- 

 cated a still further warmin<; when compared with the observations 

 taken in tliis rc/^ion oidy three weeks previously. 



PROFILE NO. 4— STATIONS 424-430 



Tiu' ."-ectioii runs fi-om the centi-al part of the Bank eastward 

 over the slo|)e and across the zone of mixed w;)ter, with its outer 

 (41(1 in offshore Atlantic water. ^Nlarch 2^ an intrusion of warm 

 salty water was observed in the surface layers between tlie forty- 

 fourth and forty-lifth pai-allels. on the east slope of the Grand 

 Bauk,-^" while to the westward a l)ody of relatively fresh warm 

 water flooded, the central part of tlie Bank. Between tliese two 

 lay frigid water, an intrusion from the North. ^'^ April 27 to May 

 1 stations 42-t to 4oO were located so as to investigate this interesting 

 region in vertical section. 



Salinifi/ — ^The freshest water Hooded 4:24 and 425. the two station-, 

 fai'thest inshore on the Bank, they being very neaidy the middle of 

 the bank. A shelf of water fresher than 32.06 ", ;„ 10 meters (n 

 fathoms) in thickness lay suspended at the mid-depths of stations 

 426 and 42T. It extended out nearly to the edge of the Bank. 

 "Watei- saltier than 30.00 °/oo. '■^ bottom cover 15 meters (8 fathoms) 

 thiek. had crept in over the Bank a distance of 48 miles from tlie 

 edge. But most striking was the mass of Atlantic water, > 35.00 ^/^,-^, 

 which extended downward to a depth of 330 meters (180 fathoms) 

 at station 429 and 200 meters (109 fathoms) at station 430. The 

 salty Atlantic water closely abutted the fresher water on the edge 

 of the Bank and tended to work inshore especialh' on the surface, 

 as indicated by the position and shape of the isohalines. The transi- 

 tion from slope to Atlantic was very abrupt. 



Temperature. — The coldest water lay 125 meters (68 fathoms) be- 

 low the surface, a shelf 120 meters (66 fathoms) thick, whose base 

 lested on the steepest part of the slope. The water, colder than 1.9° 

 and a salinity of 32.95-34.00 "/„„, was unquestionably the trunk of 

 the current with an Arctic source, which is shown in crosshatched 

 shading on the temperature section, profile No. 4. hugging closely to 

 the edge of the Bank and encroaching shorew'ard to a small extent. 



•"" Soe Oc'Pano<rinphpr's report. Marcli, p. (j4. ■^' St^c chart F. 



