The mechanic nodded, gave the big propeller blades a quarter turn and jumped back. In an instant the motor was operating, and the craft would have leaped forward and cleaved the air but for the holding ropes and blocks. Tom speeded the machinery up to almost the last notch, but those in the aerodrome hardly heard a sound. It was as though some great, silent dynamo were working.
"Fine!"
"Wonderful!"
"Wouldn't have believed it possible!"
These were some of the comments of the government inspectors.
"And now for the final test—that in the air," said Mr. Terrill.
Previous to this he and his colleagues had made a minute examination of the machinery, and had been shown the interior construction of the silencer by means of one built so that a sectional view could be had. Tom's principles were pronounced fundamental and simple.
"So simple, in fact, that it is a wonder no one thought of it before," said a navy aviation expert. "It is the last word in aircraft construction—a silent motor that will not apprise the enemy of its approach! You have done wonders, Mr. Swift!"
"I'd rather hear you say that after the air test," replied Tom, with a laugh. "Are you ready, Mr. Terrill?"
"Whenever you are."