nd, again, how was it possible to have silenced the sound of engines, the whir of a propeller, so that there should be no auditory indication whatever of a plane's presence?
Dick looked all about him. Nothing was in the air—he could have sworn it. He replaced the soaring lever and banked in a close circle, his glance piercing the night. No, there was nothing.
Crash! Boom! The plane rocked violently, tossing upon gusts of air. A huge, gaping hole of blackness had suddenly appeared in the middle of the White House lawn. The tents were flat upon the ground. Through the rising smoke clouds Dick saw tongues of flame.
No shell that, but a bomb, and dropped from the skies less than five hundred feet from where Dick hovered. Yet there was nothing visible in the skies save the round orb of the moon.
A rush of wind past Dick's face! One of the vanes of the helicopter crumpled and fluttered away into the night. Dick needed no further persuasion. The dead soldier had not lied.
Von Kettler had begun the fulfillment of his threat!
CHAPTER V
The Enemy Strikes
s Dick's airship veered and side-slipped, he kicked hard on the left rudder and brought the nose around. Furiously he sprayed the air with a leaden hail from his quick-firer. He heard a rush of wind go past him, and realized that his unseen antagonist had all but rammed him.