Abruptly he dropped the glasses and jumped up. "Hear that?" he cried.
Now the humming of the motor was again audible and growing louder every instant; and Alan, infected with the excitement of Barcus, could just make out a dark shadow that moved swiftly and steadily toward the Seaventure.
"What the devil!" he demanded, puzzled. Barcus grasped his arm excitedly.
"Quick—kick off your shoes—get set for a mile-long swim! Devil's work, all right!" he panted, divesting himself of shoes and outer garments. "I couldn't make out what they were up to till I saw them lash the wheel, light the fuse, start the motor, and take to the dory. They've made a torpedo-boat out of that tender"
He sprang upon the rail, steadying himself with a stay. "Ready?" he asked. "Look sharp!"
The two dived as one, and not until three hundred feet or more separated them from the schooner did either dare pause for a backward glance.
Then the impact of the launch against the Seaventure's side rang out across the waters, and with a roar the launch blew up, spewing skyward a wide-spread fan of flame. There followed a crackling noise, and bright flames licked out all over the schooner from stem to stern. It seemed minutes that she burned in this wise—it was probably not so
