“If the cycle of nine days holds good then we shall have the Professor at his worst to-night,” said Holmes. “The fact that these strange symptoms began after his visit to Prague, that he is in secret correspondence with a Bohemian dealer in London, who presumably represents someone in Prague, and that he received a packet from him this very day, all point in one direction. What he takes and why he takes it are still beyond our ken, but that it emanates in some way from Prague is clear enough. He takes it under definite directions which regulate this ninth-day system, which was the first point which attracted my attention. But his symptoms are most remarkable. Did you observe his knuckles?”
I had to confess that I did not.
“Thick and horny in a way which is quite new in my experience. Always look at the hands first, Watson. Then cuffs, trouser-knees, and boots. Very curious knuckles which can only be explained by the mode of progression observed by———” Holmes paused, and suddenly clapped his hand to his forehead. “Oh, Watson, Watson, what a fool I have been! It seems incredible, and yet it must be true. All points in one direction. How could I miss seeing the connection of ideas? Those knuckles—how could I have passed those knuckles? And the dog! And the ivy! It’s surely time that I disappeared into that little farm of my dreams. Look out, Watson! Here he is! We shall have the chance of seeing for ourselves.”
The hall door had slowly opened, and against the lamp-lit background we saw the tall figure of Professor Presbury. He was clad in his dressing-gown. As he
