Both were startled, although they knew that they were safe, and involuntarily they drew back.
"More will come," said Obed.

"Just as one swallow does not make a summer, one stone does not make a flight.

Ah, there it is now!" They heard that same rushing sound through the air, and a bowlder weighing at least half a ton struck in front of their log.

It did not bound away like the first, but being so much heavier buried half its weight in the earth and lay there.

Obed chuckled and regarded the big stone with an approving look.
"It's an ill stone that doesn't fall to somebody's good," he said.