OF THE UNITED STATES ARMY. 



147 



TABLE III. 



War Department, Signal Corps, U. S. Army, Meteorological Service. 



Station EUendale, N. D. (90th Meridian Time.) 



Wind Aloft Report. 



Time 8:26 A.M. Date December 5, 1918. 



TABLE IV. 



War Department, Signal Corps, U. S. Army, Meteorological Service. 



Station Mineola, L. I. (75th Meridian Time.) 



Wind Aloft Report. 



Time 7:06 A.M. Date September 7, 1918. 



as that last mentioned would move toward his objective 2 X 154. 

 or 308 miles an hour more rapidly than if he were opposed by it. 

 When it is recalled that the aviator above the clouds has no means 

 of knowing anything about the motion of the air in which he flies, 

 it will be seen that it is of the greatest importance to him to know 

 the nature of the currents at different levels. Table 4 furnishes a 

 very typical illustration of this importance. 



From the above data it is evident that an aviator flying toward 

 the west at this time and place should have flown at an altitude of 

 i,0CHD meters, while an aviator flying toward the east should have 

 flown at an altitude of 4,000 meters or more. 



