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branches — the eastern branch we have just discussed, and we will 

 now speak of the western branch and the circulation over the Grand 

 Bank. The Arctic water becomes accelerated as it floods in over 

 the broad continental shell' and pours southwestward through the 

 gulley between Newfoundland and the Grand Bank proper. Much 

 of this water swings to the right as an indraught along the south 

 coast of Newfoundland as far west as Cape Pine, while the offshore 

 water, following the bottom configuration, swerves to the left and 

 eddies eastward. During the period, March to May, the cold Arctic 

 water is at a maximum here and it spreads southward, enveloping 

 the entire Grand Bank's column, for a brief period in the surface 

 layers, and for more extended periods on the bottom. As summer 

 advances the influence of the northern icy waters becomes less 

 obvious and late season investigations find it restricted to the bottom, 

 where intermittently throughout the summer irregular, but short- 

 lived, intrusions may occur. 



The south central part of the Grand Bank is least affected by 

 Arctic influences and as summer advances the effects of freshening 

 and warming in this region become more and more emphasized, 

 more especially in the surface layers. In order that such water be 

 progressively freshened and warmed, it must receive a coastal supply. 

 This may be attributed to the general seaward expansion and east- 

 ward movement of the surface layers of low salinity to the Grand 

 Bank, interacting with the intermittent expansions of the northern 

 current from the gulley southward over the Bank. 



The picture certainly is complex. In addition to the mixing of 

 water masses over the Bank, we must not forget to take account of 

 the effects of seasonal cooling and warming which acts equally on all 

 water masses in a given region. The first signs of cooling of the sur- 

 face layers in the central part of the Bank is detected in autumn, 

 and from then on progressively lower temperatures are observed 

 which reach a minimum in February and March, when from surface 

 to bottom the convectional currents produce a uniform water column, 

 O'' to —0.5°. The following results of investigations by months of 

 the years for which we have record is given for the south central part 

 of the Bank, lat. 44° 00', long. 50° 50', which designates the center 

 of a region least affected by intrusions, and which therefore most 

 nearly approaches a purely tidal reservoir. 



