f
the detective's outrageous request. But as he noted how slight was the
figure opposing him from the other side of the threshold, he was swayed
by his natural admiration of pluck in the physically weak, and lost his
threatening attitude, only to assume one which Sweetwater secretly found
it even harder to meet.

"You are a fool," was the stinging remark he heard flung at him. "Do you
want to play the police-officer here and arrest me in mid air?"

"Mr. Brotherson, you understand me as little as I am supposed to
understand you. Humble as my place is in society and, I may add, in the
Department whose interests I serve, there are in me two men. One you
know passably well--the detective whose methods, only indifferently
clever show that he has very much to learn. Of the other--the workman
acquainted with hammer and saw, but with some knowledge too of higher
mathematics and the principles upon which great mechanical inventions
depend, you know little, and must imagine much. I was playing the gawky
when I helped you in the old house in Brooklyn. I was interested in
your air-ship--Oh, I recognised it for what it was, notwithstanding its
oddity and lack of ostensible means for flying--but I was not caught in
the whirl of its idea; the idea by which you doubtless expect, and with
very good reason too, to revolutionise the science of aviation. But
since then I've been thinking it over, and am so filled with your own
hopes that either I must have a hand in the finishing and sailing of the
one you have yourself constructed, or go to work myself on the hints you
have unconsciously given me, and make a car of my own."

Audacity often succeeds where subtler means fail. Orlando, with a
curious twist of his strong lip, took hold of the detective's arm and
drew him in, shutting and locking the door carefully behind him.

"Now," said he, "you shall tell me what you think you have discovered,
to make any ideas of your own available in the manufacture of a superior
self-propelling air-ship."

Sweetwater who had been so violently wheeled about in entering that he
stood with his back to the curtain concealing the car, answered without
hesitation.

"You have a device, entirely new so far as I can judge, by which this
car can leap at once into space, hold its own in any direction, and
alight again upon any given spot without shock to the machine or danger
to the people controlling it."

"Explain the device."

"I will draw it."

"Yo