In this case Back Cup is nothing but a lair of pirates, the Count d'Artigas is the leader of the band and Serko and Spade are his lieutenants.

I cannot get this idea out of my head, and the more I consider the more convinced I am that I am right, especially as everything I see during my stroll about the cavern seems to confirm my opinion.

However this may be, and whatever may be the circumstances that have brought them together in this place, Count d'Artigas' companions appear to accept his all-powerful domination without question. On the other hand, if he keeps them under his iron heel by enforcing the severest discipline, certain advantages, some compensation, must accrue from the servitude to which they bow. What can this compensation be?

Having turned that part of the bank under which the tunnel passes, I find myself on the opposite side of the lagoon, where are situated the storerooms containing the merchandise brought by the _Ebba_ on each trip, and which contain a great quantity of bales.

Beyond is the manufactory of electric energy. I gaze in at the windows as I pass and notice that it contains machines of the latest invention and highest attained perfection, which take up little space. Not one steam engine, with its more or less complicated mechanism and need of fuel, is to be seen in the place. As I had surmised, piles of extraordinary power supply the current to the lamps in the cavern, as well as to the dynamos of the tug. No doubt the current is also utilized for domestic purposes, such as warming the Beehive and cooking food, I can see that in a neighboring cavity it is applied to the alembics used to produce fresh water. At any rate the colonists of Back Cup are not reduced to catching the rain water that falls so abundantly upon the exterior of the mountain.

A few paces from the electric power house is a large cistern that, save in the matter of proportions, is the counterpart of those I visited in Bermuda. In the latter place the cisterns have to supply the needs of over ten thousand people, this one of a hundred--what?

I am not sure yet what to call them. That their chief had serious reasons for choosing the bowels of this island for his abiding place is obvious. But what were those reasons? I can understand monks shutting themselves behind their monastery walls with the intention of separating themselves from the world, but these subjects of the Count d'Artigas have nothing of the monk about them, and would not be mistaken for such by the most simple-minded of mortals.

I continue my way through the pillars to the extremity of the cavern. No one has sought to stop me, no one has spoken to me, not a soul apparently has taken the very slightest notice of me. This portion of Back Cup is extremely curious, and comparable to the most marvellous of the grottoes of Kentucky or the Balearics. I need hardly say that nowhere is the labor of man apparent. All this is the handiwork of nature, and it is not without wonder, mingled with awe, that I reflect upon the telluric forces capable of engendering such prodigious substructions. The daylight from the crater in the centre only strikes this part of the cavern obliquely, so that it is very imperfectly lighted, but at night, when illuminated by the electric lamps, its aspect must be positively fantastic.

I have examined the walls everywhere with minute attention, but have been unable to discover any means of communicating with the outside.

Quite a colony of birds--gulls, sea-swallows and other feathery denizens of the Bermudan beaches have made their home in the cavern. They have apparently never been hunted, for they are in no way disturbed by the presence of man.

But besides sea-birds, which are free to come and go as they please by the orifice in the dome, there is a whole farmyard of domestic poultry, and cows and pigs. The food supply is therefore no less assured than it is varied, when the fish of all kinds that abound in the lagoon and around the island are taken into consideration.