"Her defence was reserved for the Assizes. She would say nothing."
"The problem is certainly a very interesting one. The point of the letter is very obscure, is it not?"
"Well, sir," said the guide, "it seemed, if I may be so bold as to say so, the only really clear point in the whole case."
Holmes shook his head.
"Granting that the letter is genuine and was really written, it was certainly received some time before—say one hour or two. Why, then, was this lady still clasping it in her left hand? Why should she carry it so carefully? She did not need to refer to it in the interview. Does it not seem remarkable?"
"Well, sir, as you put it, perhaps it does."
"I think I should like to sit quietly for a few minutes and think it out." He seated himself upon the stone ledge of the bridge, and I could see his quick grey eyes darting their questioning glances in every direction. Suddenly he sprang up again and ran across to the opposite parapet, whipped his lens from his pocket, and began to examine the stonework.
"This is curious," said he.
"Yes, sir; we saw the chip on the ledge. I expect it's been done by some passer-by."
The stonework was grey, but at this one point it showed white for a space not larger than a sixpence. When examined closely one could see that the surface was chipped as by a sharp blow.