But these warships would invest you beyond the dangerous zone, and the _Ebba_ would not be able to put in to the ports she previously visited with the Count d'Artigas. In this event, how would you be able to provision the island?"

Engineer Serko remained silent.

This argument, which he must already have brooded over, was too logical to be refuted or dismissed, and I have an idea that the pirates contemplate abandoning Back Cup.

Nevertheless, not relishing being cornered, he continued:

"We should still have the tug, and what the _Ebba_ could not do, this would."

"The tug?" I cried. "But if Ker Karraje's secrets are known, do you suppose the powers are not also aware of the existence of the Count d'Artigas' submarine boat?"

Engineer Serko looked at me suspiciously.

"Mr. Hart," he said, "you appear to me to carry your deductions rather far."

"I, Mr. Serko?"

"Yes, and I think you talk about all this like a man who knows more than he ought to."

This remark brought me up abruptly. It was evident that my arguments might give rise to the suspicion that I was not altogether irresponsible for the recent incident. Engineer Serko scrutinized me sharply as though he would read my innermost thoughts.

"Mr. Serko," I observed, "by profession, as well as by inclination, I am accustomed to reason upon everything. This is why I communicated to you the result of my reasoning, which you can take into consideration or not, as you like."

Thereupon we separate. But I fancy my lack of reserve may have excited suspicions which may not be easy to allay.

From this interview, however, I gleaned a precious bit of information, namely, that the dangerous zone of Roch's fulgurator is between five and six miles off. Perhaps, during the next equinoctial tides, another notice to this effect in another keg may also reach a safe destination.

But how many weary months to wait before the orifice of the tunnel will again be uncovered!

The rough weather continues, and the squalls are more violent than ever. Is it the state of the sea that delays another campaign against Back Cup? Lieutenant Davon certainly assured me that if his expedition failed, if the _Sword_ did not return to St. George, another attempt under different conditions would be made with a view to breaking up this bandits' lair. Sooner or later the work of justice must be done, and Back Cup be destroyed, even though I may not survive its destruction.

Ah! why can I not go and breathe, if only for a single instant, the vivifying air outside? Why am I not permitted to cast one glance over the ocean towards the distant horizon of the Bermudas? My whole life is concentrated in one desire: to get through the tunnel in the wall and hide myself among the rocks. Perchance I might be the first to catch sight of the smoke of a squadron heading for the island.

This project, alas! is unrealizable, as sentries are posted day and night at each extremity of the passage. No one can enter it without Engineer Serko's authorization. Were I to attempt it, I should risk being deprived of my liberty to walk about the cavern, and even worse might happen to me.

Since our last conversation, Engineer Serko's attitude towards me has undergone a change. His gaze has lost its old-time sarcasm and is distrustful, suspicious, searching and as stern as Ker Karraje's.

_November 17_.--This afternoon there was a great commotion in the Beehive, and the men rushed out of their cells with loud cries.

I was reclining on my bed, but immediately rose and hurried out.

All the pirates were making for the passage, in front of which were Ker Karraje, Engineer Serko, Captain Spade, Boatswain Effrondat, Engine-driver Gibson and the Count d'Artigas' big Malay attendant.

I soon learn the reason for the tumult, for the sentries rush in with shouts of alarm.

Several vessels have been sighted to the northwest--warships steaming at full speed in the direction of Back Cup.

CHAPTER XVI.

ONLY A FEW MORE HOURS.

What effect this news has upon me, and what emotion it awakens within my soul! The end, I feel, is at hand.