59° 58° Sr _ 56° 55° 54° 53° .52° ^1°^ 50° ■49° 48° 47° 46° 45° 44° 43' 



58° 57° 56° 55° 54° 53°" 52° 51° 50° 49° 48° ,47° 46° 45° 44° 43° 



FIOURE 28.— Fourth oruise, March 24 to April 6, 1937, showinK surface isotherms, track of vessel, and ice conditions. Figures indicate date that ice was sighted or reported. 



81041—39 (Face p. 42) No. 4 



