He fired three or four shots in quick succession and then heard the sound of a plunge in the water.
Jamming his torch into the clutch of one of the tholepins, he seized the rifle and shot a quick glance ahead of him.
Jack was not to be seen, but he did see the octopus writhing and waving its frightful arms on the ledge.
"Where are you, Jack?" he shouted.
"All right!" cried Jack himself, rising just alongside the boat and holding on to the gunwale with one hand.
"I'll finish that demon before he can do any more mischief!" hissed Dick.
It was Jack falling into the water that had caused the plunge he had heard and not the return of the octopus to its element.
Now, taking quick but careful aim, Percival fired half a dozen shots from the repeating rifle he had seized and with deadly effect.
The revolver shots had wounded the octopus, but not fatally, and he might at any moment plunge into the water and seize Jack.
The heavier caliber weapon did the work.