"Sure," said Sherman. "We could do over seven hundred as a pure projectile, but we can't use that much speed and keep our maneuvering power."
CHAPTER XX
The Coming of the Green Globes
"Where to, folks?" asked Sherman, during one of their periods of soaring, as they floated high above the hilly country to the west of the Delaware River.
"Oh, most anywhere," said Ben. "I would like to see you try out this new-fangled gun of yours on something, though."
"What shall we try it on? A house?"
"No, that's too easy. We saw what it could do to things like that in the laboratory. Find a nice rock."
"O. K. Here goes. Don't give her the gun for a minute, Murray."
With wings extended, the Monitor spiralled down toward the crest of the mountain. A projecting cliff stood just beneath them, sharply outlined in the rays of the morning sun.