113 



face to bottom. Offshore the temperature rose hijjher than ■i''. a 

 figure which marks the extent to Avhich this water mass was cooled 

 by the 1923-24 winter. The water on the Newfoundland shelf, 

 colder than 0°, could not have attained such a temperature locally: 

 therefore, it must have been transported here from the north, but on 

 its landward side it had suffered considerable mixture with low- 

 salinity water expanding from the Newfoundland shores. The 

 salinity of the saltest water on the shelf corresponds to that of the 

 oceanic mass offshore but the great temperature difference disas- 

 sociates any further relationship. 



The most striking feature of this section, however, was the abrupt 

 and unquestionable transition from the Arctic water on the shelf to 

 the Avarmer saltier water offshore of the continental edge, the latter 

 contour clearly marking the point to Avhich northern water had 

 advanced. 



It is worth noting in connection with the two sections radiating 

 southeast and southwest from Cape Race that the saltest Avat'er lay 

 on the bottom of the '' gvdley,"' but on the (Irand Banks side, Avhile 

 the coldest water also lay in the bottom depths, but on the NeAvfound- 

 hmd side of the submarine valley. The freshest Avater Avas in the sur- 

 face layers Avhich extended considerably farther offshore from Cape 

 Hace to the southeast than to the soutlnvest. Such a distribution 

 may be due to the loAv-salinity .surface Avater along the east coast of 

 NcAvfoundland being set soutliAvard by the polar current, instead of 

 folloAving the normal offshore expansion of such land drainage. The 

 bulk of the Arctic Avater, Avhich normally seeks the bottom depths, 

 being deflected more to the right. floAvs in the greatest depression 

 of the shelf. Arctic Avater extended but little beyond the edge of the 

 Grand Bank, to the southeast of Cape Race, Avhere it Avas blocked 

 by the vertical side of a salter Avarmer mass. 



STATIONS 418-423 AND 428 



April 23 to 30 the patrol cruised around the Atlantic edge of the 

 Orand Bank .searching the slope Avaters for icebergs. From the 

 primary viewpoint of the ice patrol, which is safeguarding the main 

 steamship routes between Europe and United States, this zone has 

 come to be recognized as containing the richest distribution of glacial 

 ice. Oceanographic obserA^ations of these Avaters Avere taken at sta- 

 tions 418-423, located along the sloj^e at regular intervals, beginning 

 with 418, 75 miles nortliAvest of the Tail, and ending Avith 428, on 

 the northeastern part of the Bank. 



The subsurface minimum temperatures of —0.1°, —0.2°, and 

 —0.5° at stations 418, 419, and 420, respectiAely with their salinities 



