“Close that window!” he commanded, with a scowl.

I obeyed, sliding the sash to its place. But still I gazed through the glass at the labyrinth of walks and hedges defining the extensive gardens at this side of the house. I knew every inch of these grounds, having wandered there many hours during my sojourn at the mansion. And the thought came to me that it would not be difficult to escape in that maze of hedge and shrubbery, had I once a fair start of my pursuers.

Within my range of vision was a portion of the driveway, and presently I saw the Emperor’s carriage roll away, followed by several others. Piexoto was seated in the last of the carriages, but only a small portion of the Uruguayan guard accompanied the cortège.

I tried to see if the Minister of Police was among those who were returning to Rio, but was unable to note his presence in the brief time the carriages were in view. Nor did Valcour seem to be with them. Captain de Souza evidently remained in charge of the guards left at the mansion.

Well, I longed to leave the place myself, now that the emptiness of the secret vault had been disclosed; but for some reason my captors desired me to remain a prisoner.

The day dragged wearily away. One of the Uruguayans brought me food at noontime, and I ate with good appetite. The room grew close, but when I attempted to raise the window the surly guard outside presented his carbine, and I respected his wish to leave the sash lowered.

During this time I had ample opportunity to speculate upon the astonishing events of the morning; but my attempt to solve the problem of what had become of Dom Miguel and the records seemed absolutely futile. That the body of the chief had been removed by some friendly hand—the same that had saved the funds and papers—there was no doubt whatever. But when had this removal taken place?

At one time a fleeting hope animated me that the vault had been entered in time to save Dom Miguel from suffocation; but a little reflection soon caused me to abandon that notion. Allowing that the slayer of Madam Izabel had been a patriot, and left the train at the first station beyond Cruz, he could not possibly have returned to de Pintra’s mansion on the swiftest horse within eight hours of the time my friend had been entombed alive, and long before that Dom Miguel would have succumbed to the confined atmosphere of his prison.

Moreover, none of the conspirators who knew of the ring or was competent to recognize it had been on the train at the time of Izabel de Mar’s death. Therefore the patriot who finally secured the key to the vault and saved the records must have obtained the ring long after any hope of saving the life of the imprisoned chief had been abandoned.

Somehow, it occurred to me that the man in the shrubbery had not been murdered by the Mexican, but by some one of our band who had promptly cleared the vault and escaped with the contents—even while the Emperor and his party were in possession of the house. The ring might have been dropped during the escape and found by the Mexican—this being the only plausible way to account for its being in his possession.