“And he has made some wonderful ones. He told me he had discovered a chemical which mixed with gasoline will keep him in the air for twelve hours, and he is confident that he will soon double and triple its effectiveness. He has already learned how to sustain his machine for some time motionless.”
“Have you seen him do it?”
“I have,” and Harvey related the incident of the Professor dropping the giant crackers among the group on the edge of the wood.
“It is a most extraordinary achievement. I suppose he has managed to secure in some way the action of supports which operate like the wings of a bird, when he holds himself stationary in the sky.”
“Furthermore, he runs his machine without noise, which is another feat that no one else has been able to attain. It seems to me also that his ‘Dragon of the Skies,’ as he has named it, can travel faster than the swiftest eagle.”
It was in the mind of Harvey to ask the detective how he came to form the acquaintance of Professor Morgan and to inquire whether he knew the crank was in Chesterton at that moment, or had been there during the afternoon; but, as the caller did not volunteer the information, the youth forbore questioning him.
“We shall not forget that whenever and wherever we meet outside of this room, it will be as strangers. If you wish to speak to me on anything, you will take off your cap and scratch your head. If I see that, I shall accept it as notice that you have something important to say. As soon as you can do so without attracting notice you will go to your room. When the coast becomes clear I shall follow you, but prudence may require me to delay doing so for an hour or for several hours.”
At that moment both were startled by a loud knock on the door. On the instant, Detective Pendar whispered:
“Make believe you are asleep.”
Waiting, therefore, until the summons had been twice repeated, Harvey asked mumblingly: