58° 57° 56° 55; 



^^° ^^° 57° 56° 55° 54° 53° 52° ' 51° 50° 49° 48° 47° 46° 45° 44° 43° 



Figure 5.— Ice conditions and surface isotherms for the period 16-30 April 1951. Figures indicate day of month ice was sighted or reported. 



204964 O— 53 (Face p. 8) No. 5 



