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 will follow my narrative to the end.

"Early in the evening of a cool November night 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 labor. 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 and oppressed by the desolate appearance of the almost deserted street. But amongst those persons I thought I recognized more than one familiar form, and felt reassured as to the watch which had been set upon the house. The night was dark and the river especially so, but in the gloomy space beyond the dock I detected a shadow blacker than the rest, which I took for the police-boat they had promised to have in readiness in case I needed rescue from the water-side. Otherwise the surroundings were as usual, and saving the gruff singing of some drunken sailor coming from a narrow side street near by, no sound disturbed the somewhat lugubrious silence of this weird and forsaken spot.

"Pausing an instant before entering, I glanced up at the building, which was about three stories high, and endeavored to see what there was about it which had once arrested my attention, and came to the conclusion that it was its exceptional situation on the dock, and the ghostly effect of the hoisting-beam projecting from the upper story like a gibbet. And yet this beam was common to many a warehouse in the vicinity, though in none of them were there any such signs of life as proceeded from the curious mixture of sail loft, boat shop and drinking saloon, now before me. Could it be that the ban of criminality was upon the house, and that I had been conscious of this without being able to realize the cause of my interest?

"Not stopping to solve my sensations further, I tried the door, and, finding it yield easily to my touch, turned the knob and entered. For a moment I was blinded by the smoky glare of the heated atmosphere