"It was a little later than this nonsense with the dog, which was a piece of boyishness, a degree of relaxation to the strain of my fight with down-town conditions, that there came in what makes a man think the affairs of this world are not adjusted rightly, and makes recurrent the impulse which was first unfortunate for Abel--no doubt worse for Cain. There is no need for going into details of the story, how I learned, or when. My knowledge was all-sufficient and absolute. My wife and my friend were sinning, riotously and fully, but discreetly--sinning against all laws of right and honor, and against me. The mechanism of it was simple. The grounds back of my house, you know, were large, and you may not have forgotten the lane of tall, clipped shrubbery that led up from the rear to a summer-house. His calls in the evening were made early and ended early. The pinkness of all propriety was about them. The servants suspected nothing. But, his call ended, the graceful gentleman, friend of mine, and lover of my wife, would walk but a few hundred paces, then turn and enter my grounds at the rear gate I have mentioned, and pass up the arbor to the pretty summer-house. He would find time for pleasant anticipation there as he lolled upon one of the soft divans with which I had furnished the charming place, but his waiting would not be long. She would soon come to him, and time passed swiftly. "That is the prologue to my little play. Pretty prologue, isn't it?--but commonplace. The play proper isn't! The same conditions affect men differently. When I learned what I have told--after the first awful five minutes--I don't like to think of them, even now!--I became the most deliberate man on the face of this earth peopled with sinners. Sometimes, they say, the whole substance of a man's blood may be changed in a second by chemical action. My blood was changed, I think. The poison had transmuted it. There was a leaden sluggishness, but my head was clear. "I had odd fancies. I remember I thought of a nobleman who had another torn slowly apart by horses for proving false to him at the siege of Calais. His cruelty had been a youthful horror to me. Now I had a tremendous appreciation of the man. 'Good fellow, good fellow!' I went about muttering to myself in a foolish, involuntary way. I wondered how my wife's lover could endure the strain of four strong Clydesdales, each started at the same moment, one north, one south, one east, one west. His charming personal appearance recurred to me, and I thought of his fine neck. Women like a fine-throated man, and he was one. I wondered if my wife's fancy tended the same way. It was well this idea came to me, for it gave me an inspiration. I thought of the dog.