An hour later they return after having left a score of men to keep watch.  As the days at this season of the year are very short there is nothing to fear before the morrow.  It is not likely that the ships will attempt a night attack and land a storming party, for they must imagine that the place is in a thorough condition of defence.

All night long the pirates work, installing the trestles at different points of the coast.  Six have been taken through the passage to places selected in advance.

This done, Engineer Serko joins Thomas Roch in his laboratory.  Is he going to tell him what is passing, that a squadron is in view of Back Cup, and that his fulgurator will be employed to defend the island?

What is certain is that half a hundred engines, each charged with several pounds of the explosive and of the substance that ensures a trajectory superior to that of any other projectile, are ready for their work of destruction.

As to the deflagrator liquid, Thomas Roch has a certain number of phials of it, and—­I know only too well—­will not refuse to help Ker Karraje’s pirates with it.

During these preparations night has come on.  Only the lamps of the Beehive are lighted and a semi-obscurity reigns in the cavern.

I return to my cell.  It is to my interest to keep out of the way as much as possible, for Engineer Serko’s suspicions might be revived now that the squadron is approaching Back Cup.

But will the vessels sighted continue on their course in this direction?  May they not be merely passing on their way to Bermuda?  For an instant this doubt enters my mind.  No, no, it cannot be!  Besides, I have just heard Captain Spade declare that they are lying to in view of the island.

To what nation do they belong?  Have the English, desirous of avenging the destruction of the Sword, alone undertaken the expedition?  May not cruisers of other nations be with them?  I know not, and it is impossible to ascertain.  And what does it matter, after all, so long as this haunt is destroyed, even though I should perish in the ruins like the heroic Lieutenant Davon and his brave crew?

Preparations for defence continue with coolness and method under Engineer Serko’s superintendence.  These pirates are obviously certain that they will be able to annihilate their assailants as soon as the latter enter the dangerous zone.  Their confidence in Roch’s fulgurator is absolute.  Absorbed by the idea that these warship are powerless against them, they think neither of the difficulties nor menaces held out by the future.

I surmise that the trestles have been set up on the northwest coast with the grooves turned to send the engines to the north, west, and south.  On the east, as already stated, the island is defended by the chain of reefs that stretches away to the Bermudas.

About nine o’clock I venture out of my cell.  They will pay little attention to me, and perhaps I may escape notice in the obscurity.  Ah! if I could get through that passage and hide behind some rock, so that I could witness what goes on at daybreak!  And why should I not succeed now that Ker Karraje, Engineer Serko, Captain Spade, and the pirates have taken their posts outside?