When I saw the killer wave from the bridge of the Cape Horn, I took it for a natural peril; it was only much later that I realized that I might be one of the very few people to have observed a rare marine phenomenon – a monster seiche wave – at close quarters and survived.

When I joined her in 1930, the Cape Horn was an almost new, standard ‘three island’ ship of the period. The man in charge, Captain ES Wilkie, had commanded the last active square-rigged ship on the British register, and he and I were the only sailing ship men aboard.

The incident happened during a Force 9 or 10 gale in the Pacific, sometime between April and June 1935. We were nearly two weeks out of a Canadian or US west coast port taking sawn lumber to Shanghai. It was blowing hard with 25-ft (7.6m) seas and the phosphorescence given off by the breaking seas provided plenty of light to see by as I made my way over the deck-load towards the bridge. Ahead and to port one could see for a couple of miles, but the horizon was not clearly defined. The temperature was near zero.

About 4:30am, I noticed a change in the regular run of the seas ahead. A larger wave was forming, to judge from the gaps of blue water between the crests. The Chief Mate, Mr McKenzie, had the watch and I drew his attention to it. “Here’s a ‘ninth wave’ bearing down, Mister.” He examined it with the glasses, took a bearing from the ship’s compass, checked the ship’s head, then moved back to the corner window.

A ‘ninth wave’ is a common seamen’s expression, meaning a single wave larger than the others. As I kept my eyes on it, it slowly increased in size. Later, I added: “It’s not just one big wave, there are others behind it just as big. I can see their crests breaking here and there.” His left hand moved towards the engine telegraph, hesitated and drew back.

By this time the wave had become so huge that I knew it would capsize the ship. No increase in speed would save us now. I was puzzled by the slowness of the advance of the sea; we seemed to be drifting together. Then I noticed that what I had initially taken for wave crests were actually widely-spaced geysers, dancing on the upper surface. These geysers – or whatever they were – were rising to a height of about 20ft (7.6m) and dropping to half that before rising again, sometimes curving against the wind. The upper surface of the sea appeared flat and endless, stretching towards the unseen horizon. By ‘flat’ I mean there was no defined wave motion; the surface boiled gently in whorls, exactly like the water filling a lock of the Panama Canal.

I knew beyond question that I was a dead man, but the idea didn’t seem to worry me unduly. Rather, there was an absence of feeling. Suddenly I was shocked back to the present. I could plainly hear the thumping and rattling of the rocker arms of the main engine and the noise of the big exhaust in the funnel. Then, like the slamming of a watertight door, the wind dropped from a full gale to a calm. I knew what was happening; the height of the sea had cut off the wind, making a temporary lee for the ship. Glancing at the compass, I saw with surprise and delight that the ship’s head was coming up to windward. In fits and starts it moved in the right direction. I talked to her: “Hurry ‘fore the bastard wind comes back. Do it for me, lover...” stuff like that, but meaning every whispered word.

The bows were only about 30 ft (9m) off the far end of the ‘sea’ when she rammed it. Then all hell broke loose. I felt the shock as the fo’c’s’le head went in and the deck-load forrard tore loose. There was another crunching thud beneath my feet.

Just then – and with incredible speed – the whole face of the wave altered. A curtain of water rose from the sea and enclosed it. Where the existing face was deep and flat, this curtain appeared to be made of joined vertical columns about three ft (90cm) in diameter, uniform and crested, and sloping at the same angle as the great wave behind it. They looked exactly like huge steel pistons coated with oil and passed the wheelhouse windows downwards in about three seconds.

I gripped the wheel harder (for all the good it might do). The forrard windows were struck by a sea that I fully expected to demolish the whole front of the structure. This was strange; it acted like water but didn’t have the character of water with force behind it. In that instant – as if a switch had been pressed – the three front windows turned pure white, as if they had turned into three blocks of ice. In the blink of an eye it was gone, and you could see out of them again.
Then the big wave was gone. As the vessel listed heavily to port, I saw a normally big sea pass by us as the water drained from the bridge. The Old Man arrived, much to my relief, and immediately rang the telegraph. He was barefooted in soaked pyjamas and his uniform cap, shivering, for the wind had returned. He had words with the Mate (beyond my hearing), who departed at great speed. Captain Wilkie glanced briefly at the compass and said: “All right Craig. What really happened?”

His question relieved me. It meant the Mate had not seen me alter course to windward without orders. If anything had happened to anyone down below, the sea would get the blame, not me. I answered: “She wouldn’t answer her helm, sir; not enough anyway. It was the biggest sea I’ve ever seen. I’ve seen some big uns off the Horn, but nothing like this.”

After I struck the four bells at the end of the watch, I wanted a good look at the lower bridge. The stanchions on the fore part remained, but all the woodwork except the capping rail had gone. The boats were in perfect order, canvas covers intact. The afterdeck was untouched. I could hardly believe it. The fo’c’s’le had been flooded to the level of the upper tier of bunks, but this was quite normal in this run in any sort of weather. Nobody commented about it more than usual; it seemed as if nobody but the Mate and myself had seen what we went through. He never spoke about it afterwards – we never hit it off well, anyway – and neither did I.

I am left with my memory of those critical minutes, like a stretch of film with neither beginning nor end. Contrary to usual storm conditions, visibility was excellent. Wherever one looked, the air was charged with phosphorescence, and the water was alive with it. The prevailing colour of the solid water was a dark blue, with the breaking crests and ‘geysers’ showing a normal white. When the great wave had passed, the colour of the seas changed back to grey.

The wave appeared independent of the rest of the sea, while the ‘geysers’ seemed like a great pumping system, raising and lowering the water level within it. If there was any gas involved, it was imperceptible; there was no smell, and the oil lamp lighting the compass card burned steadily through the whole incident.

So what was it? Where did it come from – and where did it go after it left us? Are there ‘holes’ in the sea as there are said to be ‘black holes’ in space? I’ve often wondered. My own conclusion is that it was hollow – a gigantic bubble.