"What are you going to do—jump on him?" breathed Leonard.
"No, your plan. If you see he is going to shoot you before you get inside, jump backwards and dive."
"And remember to go far enough out not to hit the dinghy."
"Good."
Madden stared up into the mysterious vessel, caught the ladder and swung himself silently onto the rungs. Caradoc mounted close behind him. They had mounted only two or three steps, when a sudden terrific report thundered above their heads.
It was so unexpected, so violent, that the two boys almost tumbled into the sea. The next instant they found themselves wrapped in an atmosphere of hot, stifling steam. They clung to the rungs in a veritable steam-bath that roared and plunged around them. When Madden collected his senses, he realized that it was merely a safety discharge from the boilers. The main steam pressure did not strike them, but they swung in the hot wet fringe of the exhaust. Had they been ten feet farther aft, they would surely have been boiled to death. As it was they were immersed in uncomfortably hot vapor.
They clung, rather unnerved by the uproar, enduring the heat for four or five minutes, when suddenly an idea occurred to Madden. He leaned down to Caradoc and shouted in his ear.
"How about going up now? Couldn't see us in this steam."
For reply, Caradoc shoved his friend upward, and so they scrambled aloft like two monkeys.
Fortunately for them, the night was windless and the white steam drifted straight up and as it rose, it spread out in an impenetrable fog. Cloaked in this vapor, the two adventurers scrambled up some thirty-five feet to the first deck. The steam was thick inside the rail. Covered by the noisy shriek of the exhaust, they jumped inside the promenade without being heard or seen, and a moment later, they dropped arm in arm, like two casual strollers, and moved up deck.