The captain stretched out his arm from the bridge and shouted.  A minute later I would have given a great deal to have shouted too, for one-half of the sea seemed to shoulder itself above the other half, and came on in the shape of a hill.  There was neither crest, comb, nor curl-over to it; nothing but black water with little waves chasing each other about the flanks.  I saw it stream past and on a level with the Rathmines’ bow-plates before the steamer hove up her bulk to rise, and I argued that this would be the last of all earthly voyages for me.  Then we lifted for ever and ever and ever, till I heard Keller saying in my ear, ’The bowels of the deep, good Lord!’ and the Rathmines stood poised, her screw-racing and drumming on the slope of a hollow that stretched downwards for a good half-mile.

We went down that hollow, nose under for the most part, and the air smelt wet and muddy, like that of an emptied aquarium.  There was a second hill to climb; I saw that much:  but the water came aboard and earned me aft till it jammed me against the wheel-house door, and before I could catch breath or clear my eyes again we were rolling to and fro in torn water, with the scuppers pouring like eaves in a thunderstorm.

‘There were three waves,’ said Keller; ‘and the stokehold’s flooded.’

The firemen were on deck waiting, apparently, to be drowned.  The engineer came and dragged them below, and the crew, gasping, began to work the clumsy Board of Trade pump.  That showed nothing serious, and when I understood that the Rathmines was really on the water, and not beneath it, I asked what had happened.

‘The captain says it was a blow-up under the sea—­a volcano,’ said Keller.

‘It hasn’t warmed anything,’ I said.  I was feeling bitterly cold, and cold was almost unknown in those waters.  I went below to change my clothes, and when I came up everything was wiped out in clinging white fog.

‘Are there going to be any more surprises?’ said Keller to the captain.

’I don’t know.  Be thankful you are alive, gentlemen.  That’s a tidal wave thrown up by a volcano.  Probably the bottom of the sea has been lifted a few feet somewhere or other.  I can’t quite understand this cold spell.  Our sea-thermometer says the surface water is 44 deg., and it should be 68 deg. at least.’

‘It’s abominable,’ said Keller, shivering.  ’But hadn’t you better attend to the fog-horn?  It seems to me that I heard something.’

‘Heard!  Good heavens!’ said the captain from the bridge, ’I should think you did.’  He pulled the string of our fog-horn, which was a weak one.  It sputtered and choked, because the stoke-hold was full of water and the fires were half drowned, and at last gave out a moan.  It was answered from the fog by one of the most appalling steam sirens I have ever heard.  Keller turned as white as I did, for the fog, the cold fog, was upon us, and any man may be forgiven for fearing a death he cannot see.