occasionally, and Garret Jackson, the engineer, lending a hand whenever he was needed. All that afternoon work on the airship progressed. The joint inventors of it wanted to be sure that the sustaining gas bag, or aluminum container, would do its work properly, as this would hold them in the air, and prevent accidents, in case of a stoppage of the engine or propellers.
The aeroplane part of the airship was all but finished, and the motor, a powerful machine, of new design, built by Mr. Swift, was ready to be installed.
All that afternoon Tom, his father and Mr. Sharp labored in the shop. As it grew dusk there sounded from the house the ringing of a bell.
"Supper time," remarked Tom, laying aside a wrench. "I wish Mrs. Baggert would wait about an hour. I'd have this valve nearly done, then."
But the housekeeper was evidently not going to wait, for her voice supplemented the bell.
"Supper! Sup-per!" she called. "Come now, Mr. Swift; Tom, Mr. Sharp! I can't wait any longer! The meat and potatoes will be spoiled!"
"I s'pose we'd better go in," remarked Mr. Sharp, with something of a sigh. "We can finish to-morrow."
The shop, where certain parts of the airship
