“It has done mischief enough. Its day is over!” I cried. “Help me, Stackhurst! Let us end the murderer forever.”

There was a big boulder just above the ledge, and we pushed it until it fell with a tremendous splash into the water. When the ripples had cleared we saw that it had settled upon the ledge below. One flapping edge of yellow membrane showed that our victim was beneath it. A thick oily scum oozed out from below the stone and stained the water round, rising slowly to the surface.

“Well, this gets me!” cried the inspector. “What was it, Mr. Holmes? I’m born and bred in these parts, but I never saw such a thing. It don’t belong to Sussex.”

“Just as well for Sussex,” I remarked. “It may have been the southwest gale that brought it up. Come back to my house, both of you, and I will give you the terrible experience of one who has good reason to remember his own meeting with the same peril of the seas.”