A plunge deep down into the sea is confusing at the best of times.  The water thunders in the ears, and a feeling of helplessness and awe sometimes comes over the best of swimmers.  In this case, then, tangled and helpless as he was, Harry Paul could only think for a few moments of the time when he swam into the sea-cave at Pen Point at high tide, and felt the long strands of the bladder wrack curl and twist round his limbs like the tentacles of some sea-monster; and he realised once more the chilling sense of helpless horror that seemed to numb his faculties. He made an effort again and again, but each time it was weaker, and at last, with the noise of many waters in his ears, and a bewildering rush of memories through his brain, all seemed to be growing very dark around him, and then he knew no more.