e a true
physician, had not excluded the unknown and now was vindicated, and that
there are sometimes strange affairs that baffle our feeble diagnosis of
mankind....

This is merely a recital of the facts. I am not attempting to prove
anything. I merely state that, as I descended the Estabrook steps and
struck off into the park, the detective instinct which lies in every one
of us had wakened in me. It may have been the reason for my turning
around, after I had crossed the street, between the whirr and lights of
two automobiles, and stood at the opening of one of the paths of the
park.

The house I had just left met my scrutiny with a cold, impassive stare
of its own--its look might have been the stare of the sphinx or of a
good poker player. It gave no sign. My eyes traveled up to the roof,
then back again to the ground, and only when my glance dropped did I
see for the second time the lurking figure of the man.

"He was watching me from first to last," said I to myself. "He probably
saw my little strategy of waiting around the corner."

Indeed, my first impulse was to walk rapidly over the way, head him off,
and ask him his business; but I considered it unwise, and plunging into
the shadows of the wailing trees, I walked briskly toward the distant
lights that marked my district of the city.

You know, perhaps, the feeling that you are being followed. Without
recognition of any definite sight or sound, you become more and more
conscious of some one skulking in the shadows behind. Finally, you hear,
in one of those moments when the wind catches its breath, the breaking
of a twig, the disturbance among the dry leaves that have blown in
drifts over the path, and you know that some one is there.

I admit freely that I felt I had involved myself in such a manner that
some one wished to do me harm. If, on the other hand, he who followed
sought to rob me, the situation was as bad. The park was deserted. One
does not like to call for help unless certain of danger. And therefore,
though I am no longer moulded for speed, I broke into a run.

I had gone but a few paces before the other discovered that I was in
flight. I heard the rapid patter of his shoes behind me. In another
twenty feet I heard his voice. It was not loud and it was cautious, but
it reached my ears with a suggestion of extraordinary savageness.

"Stop!" it called with an oath. "I've got you. Stop!"

It was not a reassuring message, of course. I tried t