“Well, he wrote so furiously that he broke his pencil, and had, as you observe, to sharpen it again. This is of interest, Watson. The pencil was not an ordinary one. It was above the usual size, with a soft lead, the outer colour was dark blue, the maker’s name was printed in silver lettering, and the piece remaining is only about an inch and a half long. Look for such a pencil, Mr. Soames, and you have got your man. When I add that he possesses a large and very blunt knife, you have an additional aid.”

Mr. Soames was somewhat overwhelmed by this flood of information. “I can follow the other points,” said he, “but really, in this matter of the length⁠—”

Holmes held out a small chip with the letters NN and a space of clear wood after them.

“You see?”

“No, I fear that even now⁠—”