has some new wrinkles on it, and I thought you might have
evolved them yourself. Not that it's an amateur affair, by
any means!" he added hastily, as if fearing the young
inventor might resent the implication that his machine was a
home-made product.

"Yes, I originated this," answered Tom, as he put a new
turn-buckle in place; "but I didn't actually construct it--that
is, except for some small parts. It was made in the
shop--"

"Over at the army construction plant, I presume,"
interrupted the man quickly, as he motioned toward the big
factory, not far from Shopton, where aircraft for Uncle
Sam's Army were being turned out by the hundreds.

"Might as well let him think that," mused Tom; "at least
until I can figure out who he is and what he wants."

"This is different from most of those up there," and the
stranger pointed toward the circling craft on high. "A bit
more speedy, I guess, isn't it?"

"Well, yes, in a way," agreed Tom, who was lending over
his craft. He stole a side look at the man. The face was
becoming more and more familiar, yet something about it
puzzled Tom Swift.

"I've seen him before, and yet he didn't look like that,"
thought the young inventor. "It's different, somehow. Now