Numerous reports from passing vessels on the 17th and 18th 

 showed that the "B" tracks were seriously threatened by a south- 

 eastward push of scattered bergs toward 42° 40' N. 44° 50' W. Be- 

 sides mentioning this new development in the regular broadcasts, 

 special warnings were sent out at appropriate times. Recommenda- 

 tion to shift the United States-Europe tracks 60 miles south from the 

 "B" to the "A" lanes was radioed to Coast Guard headquarters on 

 the 19th. 



Earlier in the cruise the shift north of the Canadian tracks from 

 "D" to "E" on the regular scheduled date of April 10 had been 

 viewed with concern because heavy field ice and many bergs were 

 known to be along the "E" tracks between the forth-seventh and 

 forth-ninth meridians. On the 4th the Tampa had advised against 

 the putting into use of these tracks until further notice. As a matter 

 of fact they remained almost impassible until the end of the first cruise. 

 Many liners, instead of attempting to follow them, detoured around 

 the southern end of the heavy field ice that extended to near 45° 00' N. 

 48° 30' W. Those vessels that did use them were generally subjected 

 to considerable delay and, it is believed, to no little danger. 



About 75 different bergs drifted south of the forty-fifth parallel 

 during the first cruise, the majority keeping within 75 miles of the 

 eastern edge of the Grand Banks. The patrol vessel guarded particu- 

 larly the southern extension of these bergs to make sure that the 

 "B" tracks south of the Tail would not be crossed by unreported 

 ice. All the bergs watched south of the forty-third parallel were 

 small water-glazed ones near the end of their careers. 



The weather in general was rather boisterous, with man}^ strong 

 breezes and a few southwesterly gales. Visibility was remarkably 

 good throughout most of the period. Overcast nights were the rule, 

 but the s\m nearly always penetrated the cloud blanket from late 

 morning to midafternoon. 



Altogether eight oceanographic stations were occupied in scattered 

 locations. The salinities were determined in the electric salinometer 

 and the stations were fully computed before the relief by the Modoc. 

 Dr. R. MacDonald, a marine biologist from Harvard University, 

 accompanied the Tampa on the first patrol cruise for the purpose of 

 collecting specimens from surface and intermediate levels with tow- 

 nets. He made 11 successful hauls at favorable times and places, the 

 results of which will be used by him for furthering knowledge of the 

 North Atlantic fauna. 



One hundred and sixty reports of ice were received by radio from 

 ship and shore stations. In addition the patrol vessel herself sighted 

 and recorded the position of ice fifteen times. Ten vessels were 

 given special ice information. This was usually sent on request, but 

 on the 12th the Gripsholm, observed from her water temperature 



