It was a fatal pause for him. Jack gently drew his gas-gun toward him and fired. The negro threw both his hands into the air and dropped with a loud “Oof!”

But the shot had been at such close range that the powerful gas impregnated the air that Captain Andrews and his young companion were breathing. The reek of it stung their nostrils.

“We’ve got to get out of here,” whispered Jack, “or we’ll be as dead to the world as that fellow is.”

Painfully they crept on their stomachs through the thick brush, moving as silently as cats. A single mistake in their movements, the crack of a branch snapped by carelessness might, as they both knew, prove fatal. But they managed to gain a small clearing under some big trees without mishap.

It was at this moment that Jack had a sudden inspiration.

“See here,” he said excitedly, under his breath, “those chaps have worked past us now, to judge by the sounds. They think that we have fled through the woods. What’s the matter with our doubling back on our tracks and marching right into the settlement?”

Captain Andrews, ungiven as he was to emotion, fairly gasped.

“By the beard of Neptune, boy!” he exclaimed, and then, in the same breath, “but it’s not as mad a plan as it sounds. In all likelihood, almost the entire force of guards from the plantation buildings are out after us, and we ought to be more than a match for half a dozen with the gas-guns.”

“Then we’ll do it?” throbbed Jack, with a catch of his breath.

“Yes. We came here to rescue those poor chaps, and, by the Polar Star, we’ll do it if it’s possible.”