350 



Popular Science Monthly 



Hovering over the battle lines in Europe are battle 'planes of great size. The engines turn 

 over slowly, giving the 'planes a lazy speed of sixty miles an hour. When a machine rises to 

 fi^ht them off a sudden transformation takes place. Powerful engines are switched on, and 

 at tremendous speed the birds of prey rush to the battle, with their guns belching fire 



