‘It shook me far more to see you looking like a drowned rat when you came down. This is what is known ashore as “Seeing Life.”’

‘You keep a look-out with that “perisher,” my boy, and don’t worry about me. You’ve got a shirt to wear, and I haven’t, unless it’s dry before we rise.’

Presently they relapsed into silence, and Raymond dropped off to sleep again, while the ‘Sub’ carried on with the watch.

At four o’clock tea put in an appearance, after which Boyd took his turn at the periscope watch, while the others sat reading.

The wind had been increasing since noon, and the sea was getting up. Looking through the periscope his view was often obscured by the waves, and occasionally they broke right over, shutting out the scene as if a light blue curtain had been flung over the eyes and torn away again.

Even at thirty feet the boat began to roll, and when suddenly a bump was heard forward and a rattle the whole length of the boat, Raymond jumped from his chair, brought her quickly up and glanced ahead.

However, there was nothing to be seen, and he lowered the periscope, the boat descending to the patrol level again.

‘What was it?’ asked Seagrave.

The other shook his head. ‘Don’t know. One of the mysteries of the deep. Perhaps a mine that didn’t go off. Anyhow you can say so in your letters home. I heard that noise three times in an afternoon when I was in “85” last year. You never can say for certain that it’s not the moorings of a mine, so it’s always best to be on the look-out if you hear that sort of row. I don’t like them knocking to be let in in that way. It’s too forward of them altogether.’

‘I saw that “U” boat we recovered the other day when I was on leave,’ said Boyd. ‘She struck a mine end on. Great Scott! she was a sight. The whole bow-cap was blown right off, and they found the bodies of the crew in her when they got her up. Poor beggars. They’d grouped up and put the hydroplanes hard-a-rise before they were snuffed out.’