The first ice report in 1935, received on the 18th of February, 

 revealed an unbroken mass of heavy field ice extending about 100 

 miles in a general southeasterly direction, directly across Canadian 

 steamer lanes E and F. Subsequent reports established the south- 

 ward movement of this ice along the 100-fathom curve on the north- 

 eastern slope of the Grand Banks. (See fig. 4.) In response to these 

 indications the Ice Patrol cutter Mendota arrived in the critical area 

 on March 12, 1935, to observe ice conditions. Continued reports made 

 it immediately apparent that the ice fields "were moving rapidly 

 southward and many icebergs were in the cold current along the 

 eastern slope of the Grand Banks. Therefore, on jNlarch 14, the Ice 

 Patrol was inaugurated for the 1935 season. 



1935 was an unusually lieavy ice year. Not since 1929 have the 

 trans-Atlantic lanes been so seriously menaced. Field ice is much 

 more embarrassing to the shipmaster than a similar area containing 

 icebergs. The reasons for this are that, during daylight in the absence 

 of fog, a vessel maj^, with reasonable safety, thread its way among 

 bergs without being materially deviated from its course and may 

 proceed with a minimum loss of time. While it is true that a colli- 

 sion with a berg is more likely to prove fatal than running into 

 field ice, the chances of such collision are very much less. Bergs were 

 numerous this year. Over twice what is considered normal drifted 

 south of the forty-eighth parallel. Bergs were a serious threat to the 

 United States-European lanes from the middle of April to July. 7. 

 In spite of these facts the outstanding characteristic of the season v.as 

 the unusual amounts and compact character of the field ice. From the 

 first of March to the middle of April Canadian tracks E and F were 

 closed to navigation b}' field ice. Traffic along these routes, east and 

 west bound, was forced to alter its course to the southward as far 

 as latitude 45°30' K to clear the ice. (See figs. 4, 5, and 6.) This 

 circuitous route increased the distance as much as 200 miles. Of the 

 vessels that attempted to force their way through the field ice, two 

 are known to have been seriously damaged. Another ship suffered 

 sL'ght damage attempting to assist one of these two. Still another 

 vessel tried to skirt the ice to the northward, without success, and 

 finally had to take the soutliern route. This ship lost at least 3 days' 

 time, due to field ice. On the other hand, no vessel was known to 

 have struck an iceberg during this season. 



When encountering a large ice« field the shipmaster is faced with 

 the dilemma of whether to proceed through at slow speed or to 

 attempt to skirt the ice at considerable loss of time. He has the 

 following unknowns, whichever procedure he adopts : The extent 

 of the field along his track line; the character of the ice after he 

 enters the field, whether it be heavy or light, open or compact ; and, 

 which direction is the shorter distance around. The problem of de- 



