Something made him change his mind.

The faint light of stars upon rippling water came to him through the open porthole, and he shut himself in and stepped forward to the couch beneath it to look forth.
But as he moved, another influence caught him, and he stopped short.
"Is anyone here ?" he said.
Through the wash of the water he thought he heard a light movement, and he felt a presence as of some small animal in the space before him.
Swiftly he stepped back and in a moment his hand was on the switch.

The light flashed on, and in a moment he stood staring--at a fair-haired, white-faced lad in a brown livery with brass buttons who stood staring back at him with wide, scared eyes..