The two young officers waited and watched till twilight gave place to night. Presently Hiram B. Rutter strolled up to the open port.
"Having a breath of fresh air?" he inquired, affably.
"Ssh!" exclaimed Fielding, warningly. "There's a vessel over there. You can just see her starboard and masthead lights."
"Strikes me forcibly there are two red lights," said the American.
"So there are. By Jove! The villains are sending up rockets."
High above the Independencia the red glare of an exploded rocket transformed the surface of the surrounding sea into a blaze of dazzling light. Then, vanishing suddenly, the glare left the sub. and his companions blinking in the darkness.
"I know what they are doing," exclaimed Cardyke, excitedly. "They're sending up false signals of distress to lure yonder vessel within their power."
"That's it," assented Fielding. "And now's your chance to make use of your improvised flashing-lamp."
By this time the rest of the hostages were aware of the approach of another vessel, and the ports were literally jammed with human heads. But Mukyima was not content with watching. The active Jap crawled through the narrow port, balanced himself on the sill, then with a like motion drew himself up to the deck. Lying prone behind the casing of a skylight he waited till another rocket had been fired, then, mingling boldly with the pirate crew, made good use of his eyes. Unobserved, he regained the half-deck and told General Oki of what he had seen.
"Pirates get guns ready," explained Oki to Fielding. "Men are ready to capture other ship."