78 



APRIL 



No reports were received of the Gulf of St. Lawrence field ice but 

 in the Labrador Current along the eastern edge of the Grand Banks- 

 there appeared a far greater amount of all kinds of ice than usual for- 

 the season. In the first place a great amount of field ice seriously 

 obstructed navigation within the area partially bounded by lines 

 running from Cape Race to 44° 20' N., 48° 30' W., thence to 47° 30' 

 N., 46° 30' W., and thence northwestward past the forty-ninth 

 parallel, and so out of the field of observation. Everywhere this field 

 ice was more or less thickly studded with bergs. 



Toward the end of the month ship reports indicated that the limits 

 of the field ice had retreated rapidly to north of the forty-seventh 

 parallel. After the flat ice w^as melted by sun, wave, and warmer 

 water the large bergs, being much more resistant, remained to con- 

 tinue their southward drift toward the Gulf Stream waters. The 

 great majority of the April bergs were situated between the 50-fathom 

 curve of the eastern edge of the Grand Banks and a line located 60 

 miles to the eastward of it. The most southerly bergs of the month 

 were located along the direct southerly extension of this ice stream, 

 where they almost reached to the forty-second degree of north latitude 

 in longitude 49° 30' W. 



There was also a very distinct curving of ice and cold water to the 

 westward around the Tail of the Banks. If this outlet had not 

 existed it is very probable that the southward push of icy waters 

 would have been greater and woidd have sufficed to carry bergs across 

 the westbound B tracks to the south and southeast of the Tail. 



About the middle of the month reports showed that scattered bergs 

 were rapidly advancing southeastward into and across the area of 

 warm surface water to the east and west of 42° 50' N., 44° 30' W. 

 One of these bergs actually crossed the westbound B track from 

 Fastnet, in longitude 43° 50' W. This push of bergs was quite alarm- 

 ing, and was one of the factors that made the patrol recommend a 

 shift of tracks south to the extra southern or "A" lanes on April 19, 

 though, as matters turned out, after that date there were very few 

 further reports of threatening bergs in the eastern part of the ice- 

 patrol area. The warm waters rapidly melted the southeasternmost 

 of the invading bergs and their ranks were not filled by new levies 

 from the continuous procession moving south along the eastern edge. 

 During April, 1928, there was a southeasterly push of bergs very 

 similar to the one of 1929. The feature this j^ear, however, in common 

 with all ice conditions about the Grand Banks from April on, was far 

 heavier and more serious. This j^ear the patrol ships were prevented 

 by the ice just below the Tail from investigating the southeastern 

 sector themselves; therefore a careful study of the subsurface condi- 

 tions in the latter area could not be carried out. The bergs, as shown 



