It was the best thing to be done. We moved off again and the pilot kept her head towards the tunnel.

When we were about twelve yards off I gave the signal to stop. As soon as the current was turned off the Sword stopped, opened her water tanks and slowly sank again.

Then the light in the lookout was turned on again, and there in front of us was a black circle that did not reflect the lamp’s rays.

“There it is, there is the tunnel!” I cried.

Was it not the door by which I was going to escape from my prison? Was not liberty awaiting me on the other side?

Gently the Sword moved towards the orifice.

Oh! the horrible mischance! How have I survived it? How is it that my heart is not broken?

A dim light appeared in the depth of the tunnel, about twenty-five yards in front of us. The advancing light could be none other than that, projected through the lookout of Ker Karraje’s submarine boat.

“The tug! The tug!” I exclaimed. “Lieutenant, here is the tug returning to Back Cup!”

“Full speed astern,” ordered the officer, and the Sword drew back just as she was about to enter the tunnel.