"There is no harm, is there, in training a dog to pull down a stuffed figure? There is no harm, either, if the stuffed figure be given the simulated habiliments of some friend of yours. And what harm can there be in training the dog in a garden arbor instead of in a basement? I dropped into the way of being at home a little more. I told my wife she should have alternate nights at least, and she was grateful and delighted. And on the nights when I was at home I would spend half an hour in the grounds with the dog, saying I was training him in new things, and no one paid attention. I taught him to crouch in the little lane close to the summer-house, and to rush down and leap upon the manikin when I displayed it at the other end. Ye gods! how he learned to tear it down and tear its imitation throat! The training over, I would lock him in the basement as usual. But one night I had a dispatch come to me summoning me to another city. The other man was to call that evening, and he came. I left before nine o'clock, but just before going I released the dog. He darted for the post in the garden, and with gleaming eyes crouched, as he had been accustomed to do, watching the entrance of the arbor. "I can always sleep well on a train. I suppose the regular sequence of sounds, the rhythmic throb of the motion, has something to do with it. I slept well the night of which I am telling, and awoke refreshed when I reached the city of my destination. I was driven to a hotel; I took a bath; I did what I rarely do, I drank a cocktail before breakfast, but I wanted to be luxurious. I sat down at the table; I gave my order, and then lazily opened the morning paper. One of the dispatches deeply interested me. "'Inexplicable Tragedy' was the headline. By the way, 'Inexplicable Tragedy' contains just about the number of letters to fill a line neatly in the style of heading now the fashion. I don't know about such things, but it seems to me compact and neat and most effective. The lines which followed gave a skeleton of the story: "'A WELL-KNOWN GENTLEMAN KILLED BY A DOG. "'THEORY OF THE CASE WHICH APPEARS THE ONLY ONE POSSIBLE UNDER THE CIRCUMSTANCES.'