“Yes,” assented Jerry. “They’re using all the gas the generator can turn out. I only hope they don’t burst the bag, or ruin the machinery.”
“If they do, we’ll make Noddy pay for it!” cried Bob.
“That would be more bother than it would be worth,” was Jerry’s opinion. “We’ll try to get the machine away from him before he has a chance to do much damage.”
Upward the Comet mounted steadily, for those on board were evidently pushing her to the utmost. On account of the limited facilities on the aeroplane, Jerry and his chums could not go up on such a sharp slant as could their enemies, but this suited our heroes just as well.
The two airships were now comparatively close together. The Comet was still shooting upward, and the Chaser was directly below her.
Suddenly, from the upper craft, came a cry of alarm.
“They’ve discovered us!” was Bob’s opinion.
“No, they did that some time ago,” said Jerry. “I’m afraid something has happened.”
“It does seem so,” agreed Ned. “Look at that smoke!” he yelled. “She’s on fire!”
“No, it isn’t that,” was Jerry’s retort, after a quick glance at their craft through the glasses. “They’ve been using too much lifting gas, and the generator is choked. It’s escaping through the safety valve. She won’t go any higher now, but she can still go forward. We haven’t got ’em yet.”