"Sharks," was the reply, "these waters swarm with them."
CHAPTER V.
A TRAGEDY OF THE SKIES.
It was soon evident that the two men were supporting themselves in the water. Their heads made black dots on the surface beneath which the heavy deck structure of the dirigible had vanished. Through the glasses it could be seen that they were swimming about awaiting the arrival of the vessel which was rushing at her top speed to their aid.
Soon the Southern Cross was alongside and a dozen ropes and life buoys were hastily cast over the side. But even as one of the men grasped a rope's end he gave a scream of terror that long rang in the boys' ears.
At the same instant a huge, dark body shot through the water and then there was a whitish gleam as the monster shark turned on its back with its jaws open displaying a triple row of saw-like teeth.
"Quick, shoot him," cried Captain Hazzard.
But nobody had a rifle or revolver. Frank hastily darted into his cabin for his magazine weapon but when he reappeared there was only a crimson circle on the water to mark where the terrible, man-killing shark had vanished with his prey. Attracted, no doubt, by the mysterious sense that tells these sea tigers where they can snap up a meal, other dark fins now began to cut through the water in all directions.
The second man, almost overcome by the horror of his companion's fate, however, had presence of mind enough to grasp a rope's end. In a few seconds he had been hauled to the vessel's side and several of the crew were preparing to hoist him on board when two of the monsters made a simultaneous rush at him, Frank's revolver cracked at the same instant and the sea tigers, with savage snaps of their jaws, which, however, fell short of their intended prey, rolled over and vanished.
The rescued man when hauled on deck was a pitiable object. But even in his half famished condition and with the great beard that he wore there was something very familiar—strangely so—about him to the boys. Frank was the first to solve the mystery.