Mayes’s stronghold was taken, but Mayes had escaped us once again; the cage was in our hands, but the bird had flown.

Martin Hewitt, however, had his plans, as he was soon to show. The recovery of the Admiralty code was a good stroke, and was a satisfactory ending to an important case; but that, and even the capture of the curious premises behind the Barbican, made but a halting-place in his pursuit of Mayes, and as soon as I was in some degree recovered from my struggle, and the captured place had been hastily searched, the chase was resumed without a moment’s delay; and that adventure was entered upon which saw the end of the Red Triangle and its unholy doings — which came terribly near to seeing the end of Hewitt himself, in fact.

I have not described the den near the Barbican with any great particularity, but I have said that the office, accessible from the open street, was only connected with the hidden premises behind — premises, as was afterwards discovered, held under a separate tenancy — by an easily-shifted ladder. It was in these hidden premises, approached by the maze of courts and the stable-yard, that the main evidences of Mayes’s way of life were observable. The passage where my wrist had been locked to the wall, and the room or cellar in which Plummer had been confined, were the only parts of the lower premises fitted for the detention of prisoners, with the exception of one very low and wholly unlighted cellar, entered by a trapdoor and a very steep flight of brick steps. This place smelt horribly faint and stagnant; but it produced on my mind, both then and when I examined it later, an effect of horror and repulsion more than could be accounted for by the smell alone. Of its history nothing was discovered, and perhaps the feeling (though others experienced it as well as myself) was the effect of mere fancy; but I have never got rid of a conviction that that black cellar, or rather pit — for it was very narrow — had been the instrument of crimes never to be told.

There were one or two rooms sparely furnished — one as a bedroom, a larger room, with a long table, a sofa, and several chairs; and in one of the smaller rooms was found a stove, ladles and crucibles for the melting down of metals — gold or silver. It was in this same room also that the table stood, in the drawers of which were found papers, letters and formul?— things giving more than a hint of the use to which Mayes had put his friendship with Mr. Jacob Mason, for of every possible manner and detail in which science — more particularly the science of chemistry — could aid in the commission of crime, there were notes in these same drawers.

But most of these things were observed in detail later. The thing that set us once more on the trail of Mayes, that very night and that very hour, was found in the isolated office facing the street. It was a cheque-book, quite ful............