Men who die from heart disease, or any sudden natural cause, never by any chance exhibit agitation upon their features. Having sniffed the dead man's lips I detected a slightly sour smell, and I came to the conclusion that he had had poison forced upon him. Again, I argued that it had been forced upon him from the hatred and fear expressed upon his face. By the method of exclusion, I had arrived at this result, for no other hypothesis would meet the facts. Do not imagine that it was a very unheard of idea. The forcible administration of poison is by no means a new thing in criminal annals. The cases of Dolsky in Odessa, and of Leturier in Montpellier, will occur at once to any toxicologist.
"And now came the great question as to the reason why. Robbery had not been the object of the murder, for nothing was taken. Was it politics, then, or was it a woman? That was the question which confronted me. I was inclined from the first to the latter supposition. Political assassins are only too glad to do their work and to fly. This murder had, on the contrary, been done most deliberately, and the perpetrator had left his tracks all over the room, showing that he had been there all the time. It must have been a private wrong, and not a political one, which called for such a methodical revenge. When the inscription was discovered upon the wall I was more inclined than ever to my opinion. The thing was too evidently a blind. When the ring was found, however, it settled the question. Clearly the murderer had used it to remind his victim of some dead or absent woman. It was at this point that I asked Gregson whether he had enquired in his telegram to Cleveland as to any particular point in Mr. Drebber's former career. He answered, you remember, in the negative.
"I then proceeded to make a careful examination of the room, which confirmed me in my opinion as to the murderer's height, and furnished me with the additional details as to the Trichinopoly cigar and the length of his nails. I had already come to the conclusion, since there were no signs of a struggle, that the blood which covered the floor had burst from the murderer's nose in his excitement. I could perceive that the track of blood coincided with the track of his feet. It is seldom that any man, unless he is very full-blooded, breaks out in this way through emotion, so I hazarded the opinion that the criminal was probably a robust and ruddy-faced man. Events proved that I had judged correctly.
"Having left the house, I proceeded to do what Gregson had neglected. I telegraphed to the head of the police at Cleveland, limiting my enquiry to the circumstances connected with the marriage of Enoch Drebber. The answer was conclusive. It told me that Drebber had already applied for the protection of the law against an old rival in love, named Jefferson Hope, and that this same Hope was at present in Europe. I knew now that I held the clue to the mystery in my hand, and all that remained was to secure the murderer.
"I had already determined in my own mind that the man who had walked into the house with Drebber, was none other than the man who had driven the cab. The marks in the road showed me that the horse had wandered on in a way which would have been impossible had there been anyone in charge of it. Where, then, could the driver be, unless he were inside the house? Again, it is absurd to suppose that any sane man would carry out a deliberate crime under the very eyes, as it were, of a third person, who was sure to betray him. Lastly, supposing one man wished to dog another through London, what better means could he adopt than to turn cabdriver. All these considerations led me to the irresistible conclusion that Jefferson Hope was to be found among the jarveys of the Metropolis.
"If he had been one there was no reason to believe that he had ceased to be. On the contrary, from his point of view, any sudden chance would be likely to draw attention to himself. He would, probably, for a time at least, continue to perform his duties.