in the warm water after drifting south to latitude 41°50' N., longitude 

 51°13'W. (See fig. 39.) 



The ice situation during the sixth cruise, May 3 to 17, was the 

 normal result of seasonal influences at work during the last cruise. 

 The annual flooding of the Labrador Current, which normally occurs 

 in the latter part of April and the first of May, brought increasing 

 numbers of bergs into the area from the north. Although the current 

 chart delivered May 8 showed a strong cold current of normal volume 

 and velocity (averaging 0.73 knots between latitudes 46° N. and 

 43° N.) the distribution of bergs showed the major movement to be 

 still in the western branch of the Labrador Current onto the northern 

 edge of the Banks and down along the east coast of the Avalon Penin- 

 sula. The supply of bergs in the north was ample and the known 

 current provided adequate transportation; so it seemed inevitable 

 that at least a few bergs would complete the journey during May 

 southward into the steamer lanes. That this proved not to be the 

 case is shown later. It is estimated that 136 bergs drifted south of 

 latitude 48° N. during this cruise, the greatest number for any 

 cruise this year. There was an increased number of vessels attempt- 

 ing to use track F, the Cape Race route, durmg this patrol and ice 

 reports along this track showed such a number of bergs from longitude 

 46° W. to Cape Race and west to longtitude 54° W. that shipping 

 was warned off this route. The track was so strewn with bergs that 

 it was passable only in clear weather during daylight hours, making 

 it necessary for vessels on this route to stop in fog or darkness at 

 considerable loss of time. This delay, and of course danger, could 

 be avoided by a continued use of track E, which was passable in any 

 weather, using due caution, until track F was safe. (See fig. 40.) 



The seventh cruise. May 17 to 31, brought Httle real change to the 

 ice area from the last patrol. No bergs drifted south of the Tail of 

 the Banks during the whole month of May (which is unusual in 

 itself), and only a few moved as far south as latitude 45° N. Other 

 factors indicating a possible early close of the season were the usual 

 seasonal ones of increasmg air and water surface temperatures. In 

 spite of the lack of bergs in the critical area and the other influences 

 just mentioned, the situation remained threatenmg. The current 

 chart completed May 7, as mentioned above, showed a normal cold 

 current and the surface isotherms for the sixth and seventh cruises 

 (figs. 40 and 41) show an ever deepening intrusion of cold water, into 

 the warm Atlantic Current, to the south southeast of the Tail of 

 the Banks. In other words, if any berg did get south of latitude 

 44° X., there was an open highway to carry it southward across both 

 tracks B and C, to at least, latitude 41° N., and would keep the patrol 

 occupied for another month. Still, on May 31, no bergs had shown 

 any tendency to move south and the situation remained the same. 



