--this hole here close to the top
of the paper. When a man invites another man to occupy with him a
compartment which he has engaged for his own exclusive use--and this
Stavornell must have done, otherwise the man couldn't have been
travelling with him--and then proceeds to read the news instead of
troubling himself to treat his companion as a guest, it is pretty safe
to say that they are acquaintances of long standing, and upon such terms
of intimacy that the social amenities may be dispensed with
inoffensively. Now look at the position of this newspaper lying between
the dead man's feet. Curved round the ankle and the lower part of the
calf of the left leg. If we hadn't found the key we still should have
known that the murderer got out on that side of the carriage."

"How should we have known?"

"Because a paper which has simply been dropped could not have assumed
that position without the aid of a strong current of air. The opening of
that door on the right-hand side of the body supplied that current, and
supplied it with such strength and violence that the paper was, as one
might say, absolutely sucked round the man's leg. That is a positive
proof that the train was moving at the time it happened, for the day, as
you know, has been windless.

"Now look! No powder on the face, no smell of it in the compartment; and
yet the pistol found in his hand is an ordinary American-made
thirty-eight calibre revolver. We have an amateur assassin to deal with,
Mr. Narkom, not a hardened criminal; and the witlessness of the fellow
is enough to bring the case to an end before this night is over. Why
didn't he discharge that revolver to-day, and have enough sense to bring
a thimbleful of powder to burn in this compartment after the work was
done? One knows in an instant that the weapon used was an air-pistol,
and that the fellow's only thought was how to do the thing without
sound, not how to do it with sense. I don't suppose that there are three
places in all London that stock air-pistols, and I don't suppose that
they sell so many as two in a whole year's time. But if one has been
sold or repaired at any of the shops in the past six months--well,
Dollops will know that in less than no time. I 'phoned him to make
inquiries. His task's an easy one, and I've no doubt he will bring back
the word I want in short order. And now, Mr. Narkom, as our friend the
assassin is such a blundering, short-sighted individual, it's just
possible