After the match was burning well he threw it into the room and then peered after it.

There came no reply to this challenge, and so he strode in boldly, lighting another match.
The room was empty.
He saw how it was.

Betty and the man had heard the barking of the dog and had suspected the presence of an eavesdropper.

The man had fled.
Probably by this time Betty was in her room.

Calumet went out upon the porch, leaped off, and ran around the house in a direction opposite that which had marked his course when coming toward the front, covering the ground with long, swift strides.