Perhaps he had friends in hiding near by, to whom he had gone to report.

In that case his own safety demanded that he discover them before they reached the raft.

The boy had already disappeared in the timber, and there was no time to be lost in following him.
Thus reasoning, Grimshaw left the "shanty," locking its door behind him as he did so, and springing ashore, hastened up the trail, along which Winn had disappeared a few seconds before.

It took him about three minutes to reach the far edge of the timber and outskirts of the town.
Here several streets began, and as he could not follow them all, he was brought to a halt.

Which way should he go now?
He had seen nothing of the boy, whom he certainly ought to have overtaken before this, nor of any other person.