117 



purposes, constant for any one survey, the current maps are presented 

 as originally dra\vn with the reference surface given in the title differing 



54° 53° 52° of 50° 49° 



47 46° 45° 



54° 53° 52° 51° 50° 49° 48° 47° 46° 45° 



Figure 45.— Dynamic current map, from data collected March 31-April 11, 1938. 



by the appropriate amounts from the nominal value of 1,000 decibars. 

 The current maps prepared during the season were made following 

 the procedure used in the past several years. The map representing 



