How much more so in the confines of a lagoon! After five minutes' manoeuvring, the _Sword_, which was kept at about a fathom below the surface, had not succeeded in sighting the orifice.
"Perhaps it would be better to return to the surface, Lieutenant," I said.

"We should then be able to see where we are." "I think you are right, Mr.Hart, if you can point out just about where the tunnel is located." "I think I can." "Very well, then." As a precaution the light was turned off.

The engineer set the pumps in motion, and, lightened of its water ballast, the boat slowly rose in the darkness to the surface.
I remained at my post so that I could peer through the lookouts.
At last the ascensional movement of the _Sword_ stopped, and the periscope emerged about a foot.
On one side of me, lighted by the lamp by the shore, I could see the Beehive.
"What is your opinion ?" demanded the lieutenant.
"We are too far north.

The orifice is in the west side of the cavern." "Is anybody about ?" "Not a soul." "Capital, Mr.Hart.Then we will keep on a level with the surface, and when we are in front of the tunnel, and you give the signal, we will sink." 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.