THEORETICAL EFFECTS OF PRESSURE WAVES. 



227 



(a) (b) 



Fig. 71. Modified pressure distribution. 9 = 270°. 



fl = 270°, figure 71.— There has been little change in the pressure distribution due directly 

 to the wave although the pressure over the whole area has risen. As, however, the air has 

 now had time to get into motion over the whole of the Barrier the blizzard is probably 

 at its maximum at this epoch. The pressure is now -20" higher at Capo Evans in figure 716 

 than in figure 71a. 



