It was.
And further along Jack even caught sight of several more. The fierce creatures had heard the splash, and apparently scenting a fine dinner, were dashing this way and that, bent upon finding the object that had made all the rumpus.
"George, get your gun, and be ready to shoot!" said Jack, himself pale now with sudden anxiety.
So the skipper of the Wireless, understanding that this was a time to keep cool if they would save their cheery comrade, reached down under the side of his boat. When he bobbed up a few seconds later he was clutching his rifle, which he had brought along, in the faint hope that before the long cruise was done he might get a deer, or even a bear, with it.
Now the nose of the Tramp was heading straight for the spot where Nick clung to the life buoy.
"Splash as hard as you can!" shrilled Josh, who seemed to remember that sharks can sometimes be kept away by this means.
And immediately the fat boy exerted himself at a great rate, his legs and one arm beating the water until it sounded like a vast mill in action.
But as Jack cast a swift glance around he saw that the nearest shark was heading straight toward poor Nick. Jimmy had heard what was said to George. He, too, had pulled out a shotgun, and was cowering close by, holding the weapon in his hands, and with a grim look of "do or die" on his freckled face.
Bang! went the rifle in George's hands.
The bullet struck the water above the advancing monster, but seemed to do no particular damage, for they could see that he was still coming directly on.