and Mr. Damon had the Humming-Bird out on the testing ground, trying the engine, which had been keyed up to a higher pitch of speed. "I consider it perfectly marvelous, and I can't imagine how it must seem to skim along that way."
"Come and try it," urged Tom suddenly. "There's not a bit of danger. Really there isn't."
"Oh! I'd never dare do it!" replied the girl, with a gasp. "That machine is too swift by name and swift by nature for me."
"Why don't you take Miss Nestor on a grass-cutting flight, Tom?" suggested Mr. Damon. "Bless my lawn mower! but she wouldn't be frightened at that."
"Grass cutting?" repeated the girl. "What in the world does that mean?"
"It means skimming along a few feet up in the air," answered the young inventor, who had now fully recovered from the effects of the blow given him by the midnight intruder. In spite of many inquiries, no clues to his identity had been obtained.
"How high do you go when you 'cut grass,' as you call it?" asked Miss Nestor, and Tom thought he detected a note of eager curiosity in her voice.
"Not high at all," he said. "In fact, sometimes I do cut off the tops of tall daisies. Come, Mary! Won't you try that? I know you'll like
