31 



The radio compasses were invaluable in 1930 for enabling the 

 patrol vessels to find each other. It so happened that almost every 

 time relief of patrol was effected dense fog was prevailing. Despite 

 bad visibility, it was always possible to relieve the patrol on time, for 

 no matter how dense or prolonged the fog, the patrol vessels could 

 always steer toward each other along radio bearings until within 

 hearing distance of each other's fog whistles. 



Summarized radio traffic figures for 1928, 1929, and 1930 are given 

 below : 



ICE OBSERVATION 



Figures 16-23, following immediately after this section are monthly 

 ice maps. They show the positions of all icebergs and field ice south 

 of the forty-eighth meridian in the Grand Banks region either sighted 

 by or reported to the ice patrol. 



The same base map that has served for several years was used for 

 plotting the ice reports. Such uniformity makes a study of the ice 

 character of months of the same or different years very easy, either 

 through side-by-side comparision of the maps or superposition for 

 examination by transmitted light. 



The numbers appearing near the ice symbols give the day of the 

 month on which the ice reports were received. Whenever it was 

 reasonably certain that reports on the same or different days from 

 different locations referred to one berg dotted lines were drawn to 

 indicate the probable drift track of the ice. 



During March, April, and May a number of long drift tracks were 

 made for some of the southern bergs that were actually watched by 

 the patrol. Because of the longer time periods covered and the 

 absence of confusing detail, the drift tracks on the ice maps, Figures 

 21-23, are easier to follow than the same drift tracks shown on the 

 isotherm charts. Figures 4-8. 



A brief description of the 1930 season ice conditions follows. Only 

 the usual patrol area south of the forty-eighth parallel and about the 

 Grand Banks is considered. 



OCTOBER, 1929 



So far as is known, no ice drifted south of the forty-eighth paraUel 

 during the month. 



