As long as he could Reade fought drowsiness.

Again and again he opened his eyes with a start.
"I mustn't do this," Tom told himself angrily.

"No gentleman will go to sleep at the switch---when it's his train that is coming!" Yet still he found himself nodding.

Had he deemed it safe Tom would have sprung up and walked about briskly.

But this, he knew, was to invite being discovered by the returning negro.
So, at last, despite himself, Tom fell asleep.
How much time had passed he never knew.