“It must be a wild place.”
“Yes, the setting is a worthy one. If the devil did desire to have a hand in the affairs of men—”
“Then you are yourself inclining to the supernatural explanation.”
“The devil’s agents may be of flesh and blood, may they not? There are two questions waiting for us at the outset. The one is whether any crime has been committed at all; the second is, what is the crime and how was it committed? Of course, if Dr. Mortimer’s surmise should be correct, and we are dealing with forces outside the ordinary laws of Nature, there is an end of our investigation. But we are bound to exhaust all other hypotheses before falling back upon this one. I think we’ll shut that window again, if you don’t mind. It is a singular thing, but I find that a concentrated atmosphere helps a concentration of thought. I have not pushed it to the length of getting into a box to think, but that is the logical outcome of my convictions. Have you turned the case over in your mind?”
“Yes, I have thought a good deal of it in the course of the day.”
“What do you make of it?”
“It is very bewildering.”
“It has certainly a character of its own. There are points of distinction about it. That change in the footprints, for example. What do you make of that?”
“Mortimer said that the man had walked on tiptoe down that portion of the alley.”