Addison crept out and looked round, but soon came back dripping wet.
"Look here!" said he in some excitement.

"There's a freshet coming, and Lurvey's Stream is between us and Boundary Camp.

If we don't start soon, we can't get there at all." Just as he finished speaking a deep, portentous rumbling began and continued for several seconds.

The distant mountain sides seemed to reverberate with it, and at the end the whole forest shook with heavy, jarring sounds.

We both leaped out into the rain.
"What is it, Ad ?" I cried.
"Earthquake," said Addison at last.