"Try," said Thorndyke. "If you have seen the face before, you should be able to recall the person."
I looked intently at the photograph, and the more I looked, the more familiar did the face appear. Suddenly the identity of the man flashed into my mind and I exclaimed in astonishment:
"It can't be that poor creature at Kennington, Mr. Graves?"
"I think it can," replied Thorndyke, "and I think it is. But could you swear to the identity in a court of law?"
"It is my firm conviction that the photograph is that of Mr. Graves. I would swear to that."
"No man ought to swear to more," said Thorndyke. "Identification is always a matter of opinion or belief. The man who will swear unconditionally to identity from memory only is a man whose evidence should be discredited. I think your sworn testimony would be sufficient."
It is needless to say that the production of this photograph filled me with amazement and curiosity as to how Thorndyke had obtained it. But, as he replaced it impassively in its envelope without volunteering any explanation, I felt that I could not question him directly. Nevertheless, I ventured to approach the subject in an indirect manner.
"Did you get any information from those Darmstadt people?" I asked.
"Schnitzler? Yes. I learned, through the medium of an official acquaintance, that Dr. H.
