ays I lay low, waiting for a
suitable time in which to make my final attempt to penetrate this
mystery.

I knew that for the adventure I was now contemplating considerable
courage was required. But I did not hesitate. The time had come for me
to show my mettle. In the few communications I was enabled to hold with
my superiors I told them of my progress and arranged with them my plan
of work. As we all agreed that I was about to encounter no common
villainy, these plans naturally partook of finesse, as you will see if
you follow my narrative to the end.

Early in the evening of a cool November day I sallied forth into the
streets, dressed in the habiliments and wearing the guise of the wealthy
old gentleman whose secret guest I had been for the last few days. As he
was old and portly, and I young and spare, this disguise had cost me no
little thought and labour. But assisted as I was by the darkness, I had
but little fear of betraying myself to any chance spy who might be upon
the watch, especially as Mr. L---- had a peculiar walk, which, in my
short stay with him, I had learned to imitate perfectly. In the lapel of
my overcoat I had tied a tag of blue ribbon, and, though for all I knew
this was a signal devoting me to a secret and mysterious death, I walked
along in a buoyant condition of mind, attributable, no doubt, to the
excitement of the venture and to my desire to test my powers, even at
the risk of my life.

It was nine o'clock when I reached South Street. It was no new region
to me, nor was I ignorant of the specified drinking den on the dock to
which I had been directed. I remembered it as a bright spot in a mass of
ship-prows and bow-rigging, and was possessed, besides, of a vague
consciousness that there was something odd in connection with it which
had aroused my curiosity sufficiently in the past for me to have once
formed the resolution of seeing it again under circumstances which would
allow me to give it some attention. But I never thought that the
circumstances would involve my own life, impossible as it is for a
detective to reckon upon the future or to foresee the events into which
he will be hurried by the next crime which may be reported at police
headquarters.

There were but few persons in the street when I crossed to The Heart's
Delight--so named from the heart-shaped opening in the framework of the
door, through which shone a light, inviting enough to one chilled by the
keen November air an