"What are they, Mr. Holmes?"
I stepped to my bureau and brought out an enlarged photograph. "This is my method in such cases," I explained.
"You certainly do things thoroughly, Mr. Holmes."
"I should hardly be what I am if I did not. Now let us consider this weal which extends round the right shoulder. Do you observe nothing remarkable?"
"I can't say I do."
"Surely it is evident that it is unequal in its intensity. There is a dot of extravasated blood, here, and another there. There are similar indications in this other weal down here. What can that mean?"
"I have no idea. Have you?"
"Perhaps I have. Perhaps I haven't. I may be able to say more soon. Anything which will define what made that mark will bring us a long way towards the criminal."
"It is, of course, an absurd idea," said the policeman, "but if a red-hot net of wire had been laid across the back, then these better-marked points would represent where the meshes crossed each other."
"A most ingenious comparison. Or shall we say a very stiff cat-o'-nine-tails with small hard knots upon it?"