he throbbing of the engines went on at an unvarying tempo. There was the slight, almost infinitesimal tremor of their vibration. The electric light in the cabin wavered rhythmically with its dynamo. From the open porthole came the sound of washing water. Now and then a disconnected sound of laughter or of speech came down from the main saloon.
Ortiz lay upon the bed, exhausted.
"It is perhaps humorous, Senor Bell," he said presently, in the same steady voice he had used upon the deck. "It is undoubtedly humorous that I should call upon you. I believe that you are allied with the Secret Service of your government."
Bell started to shake his head, but was still. He said nothing.
"I am poisoned," said Ortiz. He tried to smile, but it was ghastly. "It is a poison which makes a man mad in a very horrible fashion. If I could use my hands—and could trust them—I would undoubtedly shoot myself. It would be entirely preferable. Instead, I hope—"
He broke off short and listened intently. His forehead beaded.
"Is that an airplane motor?"
Bell went to the port and listened. The washing of waves. The throbbing of the ship's engines. The dismal, long-drawn-out moaning of the fog-horn. Nothing else.... Yes! A dim and distant muttering. It drew nearer and died away again.
"That is a plane," said Bell. "Yes, It's out of hearing now."