and at such a time? Those are
the things that brought the suspicion into my mind; the certainty,
however, had to be brought about beyond dispute before I could act.

"I knew that George Carboys had returned to that studio by the dry marks
of muddy footprints, that were nothing like the shape of Van Nant's,
which I found on the boards of the veranda and on the carpet under one
of the windows; I knew, too, that it was Van Nant who had sent that
pigeon. You remember when I excused myself and went back on the pretext
of having forgotten my magnifying glass the other day? I did so for the
purpose of looking at that fifth pigeon. I had observed something on its
breast feathers which I thought, at first glance, was dry mud, as though
it had fallen or brushed against something muddy in its flight. As we
descended the stairs I observed that there was a similar mark on Van
Nant's sleeve. I brushed against him and scraped off a fleck with my
fingernails. It was the dust of dried modelling clay. That on the
pigeon's breast proved to be the same substance. I knew then that the
hands of the person who liberated that pigeon were the hands of some one
who was engaged in modelling something or handling the clay of the
modeller, and the inference was clear.

"As for the rest: when Van Nant entered that studio to-night, frightened
half out of his wits at the knowledge that he would have to deal with
the one detective he feared, I knew that if he approached that statue
and made any attempt to examine it I should have my man, and that the
hiding-place of his victim's body would be proved beyond question. When
he did go to it, and did examine it---- Clarges Street at last, and
thank fortune for it, as I am tired and sleepy. Stop here, chauffeur.
The riddle is solved, Mr. Narkom. Good-night!"

CHAPTER VII

THE RIDDLE OF THE 5.28

It was exactly thirty-two minutes past five o'clock on the evening of
Friday, December 9th, when the station-master at Anerley received the
following communication by wire from the signal box at Forest Hill:

5.28 down from London Bridge just passed. One first-class
compartment in total darkness. Investigate.

As two stations, Sydenham and Penge, lie between Forest Hill and
Anerley, in the ordinary course of events this signal-box message would
have been despatched to one or the other of these; but it so happens
that the 5.28 from London Bridge to Croydon is a special train, which
makes no s