"Before we go any farther," said Platzoff, "I may as well explain to you how it happens that a respectable old country-house like Bon Repos has such a suspicious-looking hiding-place about its premises. You must know that I bought the house, many years ago, of the last representative of an old north-country family. He was a bachelor, and in him the family died out. Three years after I had come to reside here the old man, at that time on his death-bed, sent me a letter and a key. The letter revealed to me the secret of the place we are now exploring, of which I had no previous knowledge; the key is that of the two iron doors. It seems that the old man's ancestors had been deeply implicated in the Jacobite risings of last century. The house had been searched several times, and on one occasion occupied by Hanoverian troops. As a provision against such contingencies this hiding-place (a natural one as far as the cavern beyond is concerned, which has probably existed for thousands of years) was then first connected with the interior of the house, and rendered practicable at a moment's notice; and here on several occasions, certain members of the family, together with their plate and title-deeds, lay concealed for weeks at a time. The old gentleman gave me a solemn assurance that the secret existed with him alone; all who had been in any way implicated in the earlier troubles having died long ago. As the property had now become mine by purchase, he thought it only right that before he died these facts should be brought to my knowledge. You may imagine, my dear Ducie, with what eagerness I seized upon this place as a safe depository for my Diamond, which, up to that time, I had been obliged to carry about my person. And now, forward to the heart of the mystery!"
Having unlocked and flung open the second iron door, Platzoff took up his lamp, and, closely followed by Ducie, entered a narrow winding passage in the rock. After following this passage, which tended slightly downwards for a considerable distance, they emerged into a large cavernous opening in the heart of the hill.
Platzoff's first act was, by means of a long crook, to draw down within reach of his hand a large iron lamp that was suspended from the roof by a running chain. This lamp he lighted from the hand-lamp he had brought with him. As soon as released, it ascended to its former position, about ten feet from the ground. It burned with a clear white flame that lighted up every nook and cranny of the place. The sides of the cave were of irregular formation. Measuring by the eye, Ducie estimated the cave to be about sixty yards in length, by a breadth, in the widest part, of twenty. In height it appeared to be about forty feet. The floor was covered with a carpet of thick brown sand, but whether this covering was a natural or an artificial one Ducie had no means of judging. The atmosphere of the place was cold and damp, and the walls in many places dripped with moisture; in other places they scintillated in the lamplight as though thousands of minute gems were embedded in their surface.
In the middle of the floor, on a pedestal of stones loosely piled together, was a hideous idol, about four feet in height, made of wood, and painted in various colours. In the centre of its forehead gleamed the great Diamond.
"Behold!" was all that Platzoff said, as he pointed to the idol. Then they both stood and gazed in silence.
Many contending emotions were at work just then in Ducie's breast, chief of which was a burning, almost unconquerable desire to make that glorious gem his own at every risk. In his ear a fiend seemed to be whispering.
"All you have to do," it seemed to say, "is to grip old Platzoff tightly round the neck for a couple of minutes. His thread of life is frail, and would be easily broken. Then possess yourself of the Diamond and his keys. Go back by the way you came and fasten everything behind you. The household is all abed, and you could get away unseen. Long before the body of Platzoff would be discovered, if indeed it were ever discovered, you would be far away and beyond all fear of pursuit. Think! That tiny stone is worth a hundred and fifty thousand pounds."
This was Ducie's temptation. It shook him inwardly as a reed is shaken by the wind. Outwardly he was his ordinary quiet impassive self, only gazing with eyes that gleamed on the gleaming gem, which shone like a new-fallen star on the forehead of that hideous image.
The spell was broken by Platzoff, who, going up to the idol, and passing his hand through an orifice at the back of the skull, took the Diamond out of its resting-place, close behind the hole in the forehead, through which it was seen from the front. With thumb and forefinger he took it daintily out, and going back to Ducie dropped it into the outstretched palm of the latter.
Ducie turned the Diamond over and over, and held it up before the light between his forefinger and thumb, and tried the weight of it on his palm. It was in the simple form of a table diamond, with only sixteen facets in all, and was just as it had left the fingers of some Indian cutter a couple of centuries ago. It glowed with a green fire, deep, yet tender, that flashed through its facets and smote the duller lamplight with sparkles of intense brilliancy. This, then, was the wondrous gem that many a time and oft had felt the touch of great Aurengzebe's hand! Ducie seemed to be examining it most closely; but, in truth, at that very moment he was debating in his own mind the terrible question of murder or no murder, and scarcely saw the stone itself at all.