It was certain they were not trying to take his life; had they wished they could have done that long ago, and while one lived one was never wholly lost.

It was a fact that he would remember through everything and he would pin his faith to it.
He slept, after a while, and he always thought afterwards that the foul, dense air of the cabin added a kind of stupor to sleep.

When he came out of it late the next day he was conscious of an immense heaviness in the head and of a dull, apathetic feeling.

He sat up slowly and painfully as if he were an old man.

Then he noticed that the porthole was open again, but, judging from the quality of the air in the cabin, it had not been open long.
So the slaver had been successful.