“I must really apologise,” said the Russian, next moment, “for keeping you waiting so long; but this lamp will not burn properly.”

“Don’t hurry yourself on my account,” said Ducie.  “I am quite jolly.  My eyes are ready bandaged; I am only waiting for the axe and the block.”

“We are not going to dispose of you in quite so summary a fashion,” said the Russian.  “One minute more and your eyesight shall be restored to you.”

Ducie’s quick ears caught a low click, as though someone had touched a spring.  Then there was a faint rumbling, as though something were being rolled back on hidden wheels.

“Lend me your hand again, and bend that tall figure of yours.  Step carefully.  There is another staircase to descend—­the last and the steepest of all.”

Keeping fast hold of Platzoff’s hand, Ducie followed slowly and cautiously, counting the steps as he went down.  They were of stone, and were twenty-two in number.  At the bottom of the staircase another door was unlocked.  The two passed through, and the door was shut and relocked behind them.

“Be blind no longer!” said Platzoff, taking off the handkerchief and handing it to Ducie, with a smile.  A few seconds elapsed before the latter could discern anything clearly.  Then he saw that he was in a small vaulted chamber about seven feet in height, with a flagged floor, but without furniture of any kind save a small table of black oak on which Platzoff’s lamp was now burning.  The atmosphere of this dungeon had struck him with a sudden chill as he went in.  At each end was a door, both of iron.  The one that had opened to admit them was set in the thick masonry of the wall; the one at the opposite end seemed built into the solid rock.

“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,