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of the sun from striking the ice. During 1929 one herg southeast of 

 the Tail approached on a cloudy night was seen when the beams of a 

 searchlight were pla3"ed on it to be pouring off water from all visible 

 surfaces, just as so usually happens during the day. 



Notwithstanding the need for further observation and study, the 

 observations which the ice patrol has been able to make to date permit 

 some conclusions to be drawn about the life of bergs south of the 

 forty-fourth parallel. Two late instances will be given. 



A berg of not less than 500,000 short tons mass was seen by the 

 patrol for the first time on July 17, 1929, about 55 miles south- 

 southeast of the Tail. It was in water close to 60° F. at the surface 

 at this time and remained in such water throughout the remainder of 

 its life. It disappeared entirely late on July 26, nine days after it 

 had been first sighted. The berg was a rather sohd one and this 

 disintegration was considered quite rapid. A berg of about the same 

 size in 1928 lasted south of the Tail from May 21 to June 4, a period of 

 14 days. The time was earlier in the season and the water was con- 

 siderably colder during most of this time. In fact, it was in surface 

 water colder than 38° F. from May 21 to May 25. Both of the above 

 bergs were larger than the average berg that gets below the forty- 

 fourth parallel, being of the approximate size of the generously large 

 berg taken in section 3 of this chapter as the average size which crosses 

 the forty-eighth parallel. 



The experience of the ice patrol all goes to show that in the 50° to 

 60° surface water south and east of the Grand Banks the average berg 

 can be counted on under all ordinary circumstances to be entirely 

 melted in from 7 to 10 days. Only extremely large and resistant bergs 

 are able to survive longer in water warmer than 50° F. 



It was computed in the section of this chapter dealing with glacial 

 ice totals that the abnormally heavy 1929 ice season provided only 

 enough ice south of the forty-eighth parallel to cover the "melting 

 area" of 74,000 sc{uare sea miles with a film of ice one-eighth inch 

 thick. The only reason why the glacial ice reaches so much lower 

 latitudes and persists south of the forty-eighth parallel each season two 

 to three months longer than the field ice does is because of its con- 

 centration in the large masses known as icebergs. If it were not so 

 concentrated it would vanish overnight and never reach the 50° and 

 60° water east and south of the Banks. 



The field ice so prevalent during the first third of the ice patrol 

 season in the northern half of the "melting area" and in the regions 

 to the north of that, has an enormous preservative influence on the 

 bergs. If there were no field ice oft' the Labrador and Newfoundland 

 coasts in the winter and spring there would be far less of a berg 

 problem along the trans-Atlantic tracks than there now is. The 

 field ice has been credited with acting as a fender which keeps the 



