"Who is it?" Leonard asked.

She shook her head.

"Wait," she begged.

A few days later, we were invited to a picnic party at Greymarshes Bay to celebrate Arthur's supposed twentieth birthday. Duncombe had hired a little petrol launch, and we took our lunch and bathing clothes along the coast. It was a hot, almost breathless day, and we entered the water eagerly for our pre-luncheon bathe. Every one except Mrs. Scatterwell bathed, and she busied herself with one of the servants, preparing luncheon in a shady spot. Somehow or other, perhaps because of the brilliancy of the weather, every one was in better spirits. Even Duncombe and his pupil seemed to be on quite good terms. They vied with one another in diving feats, and Arthur, exulting in his one accomplishment, clambered up the rocks more than once to a considerable height, before he made his plunge. Presently, however, we all tired a little of the sport. Rose was already dressing in a convenient cave. I was lying at full length, enjoying a sun bath on the shingle, when I heard Duncombe's voice from behind a great rocky promontory jutting out from the sea a little to my left.

"One more, Arthur. I've found a new place. It's the best of the lot."

I watched the young man climb obediently up the jagged boulder of rock. The topmost ledge must have been at least twenty or thirty feet high, and he was well on his way to it, with his back turned to me, when I became conscious of a queer feeling of apprehension. The space of water into which Arthur was to plunge was out of my sight, but there was a little foam at the corner, and I remembered how once on a stormy day I had stood and seen the broken waves thunder along this opening. I rose to my feet, waded in as far as I could, and swam on my side towards the promontory. Arthur by now had reached the summit and was cautiously scrambling to his feet. There was no sign anywhere of Duncombe. I swam on a few more strokes, until I was suddenly conscious of a current. I swam round it, until I was directly facing Arthur, now standing upright and commencing to poise.

"Wait a moment, Arthur," I called out.

"Get out of the way, then," he replied. "I'm coming over. Where's Duncombe?"

I looked around but there was no sign of him, yet I knew very well that he could not be more than a few yards away.

"One moment, Arthur," I shouted back.