Chapter XVI. Tom is Worried - Page 2

replaced. When it was lowered to the deck it was carefully examined.

"What made it break?" Ned wanted to know.

"That's a question I can't answer," Tom replied. "There may have been a defect in the wood, but I had it all carefully examined before I used it."

The propeller was one of the "built-up" type, with alternate layers of ash and mahogany, but some powerful force had torn and twisted the blades. The wood was splintered and split, and some jagged pieces, flying off at a tangent, so great was the centrifugal force, had torn holes in the strong gas bag.

"Did something hit it; or did it hit something?" asked Ned as he saw Tom carefully examining the broken blades.

"Hard to say. I'll have a good look at this when we get back. Just now I want to finish that gun test we didn't get a chance to start."

"You don't mean to say you're going to keep on, and with the balloon damaged; are you?" cried Mr. Damon, in surprise.

"Certainly--why not?" Tom replied. "In warfare accidents may happen, and if the Mars can't go on, after a little damage like this, what is going to happen when she's fired on by a hostile ship? Of course I'm going on!"

"Bless my necktie!" ejaculated the odd man.

"That's the way to talk!" exclaimed Lieutenant Marbury. "I'm with you."

There really was very little danger in proceeding. The Mars was just as buoyant as before, for more gas had been automatically made, and forced into the uninjured compartments of the bag. At the same time enough sand ballast had been allowed to run out to make the weight to be lifted less in proportion to the power remaining.

True, the speed would be less, with two propellers instead of three, and the craft would not steer as well, with the torn ends of the gas bag floating out behind. But this made a nearer approach to war conditions, and Tom was always glad to give his inventions the most severe tests possible.

So, after a little while, during which it was seen that the Mars was proceeding almost normally, the matter of discharging the guns was taken up again.

The weapons were all ready to fire, and when Tom had attached the pressure gauges to note how much energy was expended in the recoil, he gave the word to fire.

The two big weapons were discharged together, and for a moment after the report echoed out among the cloud masses every soul on the ship feared another accident had happened.

For the big craft rolled and twisted, and seemed about to turn turtle. Her forward progress was halted, momentarily, and a cry of fear came from several of the members of the crew, who had had only a little experience in aircraft.

"What's the matter?" cried Ned. "Something go wrong?"

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