92 



and the work was bent wholly towards contributing direct practical 

 information on the behavior of those icebergs that drifted south of 

 the Tail of the Grand Bank. In the course of the season a total of 

 76 stations were taken, all but three of which were occupied in the 

 deep water off the slope to a depth of 750 meters. This number of 

 stations is less than for 1923 or for 1924; but their value was conse- 

 quently greatly enhanced by their being well distributed over the area 

 to be surveyed, with each station in the set taken in rapid succession. 

 We were handicapped during the early part of the season by the 

 breaking down of the oceanographic winches on board both the 

 Tampa and the Modoc, so that the first set of stations was not actually 

 begun until April 29, after the patrol had been in progress more 

 than a month. It was deemed best to make a general survey of the 

 entire ice area at the beginning of the season and a second one at its 

 close. During the progress of the season it was not found possible 

 to make more than one survey and this was confined to a compara- 

 tively small but important area off the southwest slope of the Bank. 

 The critical ice area is of such great extent that it requires at least a 

 total of 12 to 14 stations to delineate the courses of the currents with 

 any accuracy. A satisfactory survey of the entire region around 

 the Tail was afforded by Sets I and III with a total of 26 stations. 



SOME FEATURES REVEALED BY THE VERTICAL SECTIONS 



The vertical sections show the distribution of temperature, salinity, 

 and specific volume for the following groups of stations : 



Section I: West-southwest slope, stations 558-560, figures 29 

 and 30. 



Section II: Southwest slope, stations 557-565, figures 31 and 32. 



Section III: South slope, stations 566-570, figures 33 and 34. 



Section IV: Southeast slope, stations 571-576, figures 35 and 36. 



Section V: East slope, stations 578-581, figures 37 and 38. 



Section VI: West-southwest, station 607-609, figures 39 and 40. 



Section VII: Southwest slope, station 610-614, figures 41 and 42. 



Section VIII: South slope, station 615-619, figures 43 and 44. 



Section IX: Southeast slope, station 620-630, figures 45 and 46. 



Section X: East slope, station 622-625, figures 47 and 48. 



Since vertical sections normal to the Grand Bank slopes have been 

 taken and discussed repeatedly in former ice seasons, only brief com- 

 ment on the principal features is called for. 



Section I: The striking thing about this profile, Figure 29, is the 

 shelf of icy water (temperature below^ 0° C), that hugged the slope 

 between i(>0' and 200 meters, and extended out about 20 miles from 

 the edge. The density wall, as illustrated in Figure 30, was well 

 developed at the time with its highest point approximately 45 miles 

 seaward from the slope. 



