Next day we were the best of friends, and we got leave to go ashore for a few hours.  We were anchored in Grassy Bay, off Ireland Island—­that is, off the island where the hulks are, and where the school-master spent those ten long years.  Alister and Dennis wanted to take a boat and make for Harrington Sound, a very beautiful land-locked sheet of water, with one narrow entrance through which the tide rushes like a mill-race, but when they heard my reason for wanting to have a look at my friend’s old place of labour and imprisonment, they decided to stay with me, which, as it happened, was very lucky for us all.

We were all three so languid, that though there was much to see and little time in which to see it, when we found three firm and comfortable resting-places among the blocks of white stone in the dockyard, we sat down on them, and contented ourselves with enjoying the beautiful prospect before us.  And it so happened that as Dennis said, “if we’d taken a box for the Opera” we could not have placed ourselves better for the marvellous spectacle that it was our good luck to witness.  I must try and tell it in order.

The first thing we noticed was a change among the sea-birds.  They left their careless, graceful skimming and swooping, and got into groups, wheeling about like starlings, and uttering curious cries.  And scarcely had we become conscious of this change among the birds, than a simultaneous flutter ran through the Bermudian “rig-boats” which had been skimming with equal carelessness about the bay.  Now they were hurriedly thrown up into the wind, their wide mainsails lowered and reefed, whilst the impulse spread as if by magic to the men-of-war and ships in the anchorage.  Down came the sails like falling leaves, the rigging swarmed with men bracing yards, lowering top-gallant masts, and preparing—­we could not conceive for what.

“What, in the name of fortune—­” said Dennis.

But at this moment Alister cried, “Look behind ye, man!”

We turned round, and this was what we saw:—­

The sky out to seaward was one great half-circle of blue-black, but in what sailors call the eye of the storm was another very regular patch, with true curved outlines of the arc and the horizon.  Under this the sea was dazzlingly white, and then in front of that it was a curious green-black, and it was tossing and flopping about as if it did not know what to be at.  The wind was scarcely to be felt as wind, but we could hear it moaning in a dull way that was indescribably terrifying.  Gradually the blackness seemed to come down over us as if it would swallow us up, and when I looked back to the bay not a bird was to be seen, and every boat was flying into shelter.

And as they fled, there arose from the empty sea and sky a strange hissing sound, which gradually grew so intense that it became almost a roar; and, as the noise increased, the white line on the horizon widened and widened.