"Be careful, Jack!" Samms cautioned, sharply. "Don't touch it—it may be charged, or worse."
Jack took the metal cover, which he was still holding, and by working it back and forth edgewise in the sand, made of it a vertical barrier squarely across the thing's path. The traveler paid no attention, did not alter its steady pace of a couple of miles per hour. It measured about twelve inches long over all; its paddle-wheel-like extremities were perhaps two inches wide and three inches in diameter.
"Do you think it's actually alive, sir? In a place like this?"
"I'm sure of it. Watch carefully."
It struck the barrier and stopped. That is, its forward motion stopped, but its rolling did not. Its rate of revolution did not change; it either did not know or did not care that its drivers were sl
