loonist was now in a fair way to have the difficulty solved.
His airship was, primarily an aeroplane, but with a sustaining aluminum container, shaped like a cigar, and filled with a secret gas, made partly of hydrogen, being very light and powerful. It was testing the effect of this gas on a small model of the aluminum container that the explosion, told of in the first chapter, occurred. In fact it was only one of several explosions, but, as Tom said, all the while they were eliminating certain difficulties, until now the airship seemed almost a finished thing. But a few more details remained to be worked out, and Mr. Swift and his son felt that they could master these.
So it was with a feeling of no little elation, that the young inventor followed Mr. Sharp into the shop. The balloonist, it may be explained, had been invited to live with the Swifts pending the completion of the airship.
"Do you think we'll get on the right track if we put the needle valve in?" asked Tom, as he noted with satisfaction that the damage from the explosion was not great.
"I'm sure we will," answered the aeronaut. "Now let's make another model container, and try the gas again."
They set to work, with Mr. Swift helping them
