“I don’t exactly understand what makes the airship move,” confessed the newspaper man to the self-appointed instructor. “Is it——?”
“It’s these here perpellers,” explained the constable. “They work just like an electric fan, you know.”
“I see, but then the blades of an electric fan go around but the fan doesn’t sail in the air. Why is that?”
“Well—er—it’s because—Oh, here’s something I forgot to explain,” said the constable quickly, finding himself unexpectedly in deep water. “I’ll tell you about the perpellers later. This here’s the radiator,” he went on. “It’s full of water, just like in the radiator of an automobile, and it keeps the gasoline from boiling over—cools it off you know.”
“Indeed,” said the reporter, who knew a little about autos. “But I thought the water was to keep the engine from getting overheated.”
“Not in an airship,” insisted the constable. “In an airyplane the radiator keeps the gasoline cool. I’ll jest show you how it works,” and, before Dave could stop the man, he had opened a small faucet in the radiator, designed to drain out the water.
Now it happened that Dave had been running his engine very fast, and, in consequence, the water in the radiator—which really did cool the motor and not the gasoline—this water was very hot—in fact some steam was present.
No sooner did the meddlesome constable open the stop-cock that a jet of steam shot out, burning his fingers severely. The man jumped back with an exclamation of pain.
“I—I didn’t know it was so hot!” he cried. “This must be a new cooling system he’s using on this affair.”
“I should say it was more like a heating system,” remarked the reporter, with a smile he could not conceal.