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.'

"I read the dispatch at length. A man is naturally interested in the
news from his own city. It told how a popular club man had been found in
the early morning lying dead in the grounds of a friend, his throat torn
open by a huge dog, an Ulm, belonging to that friend, which had somehow
escaped from the basement of the house, where it was usually confined.
The gentleman had been a caller at the residence the same evening, and
had left at a comparatively early hour. Some time later the mistress of
the place had gone out to a summer-house in the grounds to see that the
servants had brought in certain things