Touching the plate once more he pushed it back to its original position, and found that it remained stationary. As long as he kept on the outward side he was safe, and if the Secretary observed this rule he could easily avail himself of the plate to descend by, for the perpetrators of the villainous arrangement had evidently not thought it necessary to make it entirely revolve, as one who had once gone up the tower was never expected to come down the outside again. And now, with great caution, he wormed his way to the treacherous step, and with still greater care placed his foot on its outer edge; it held firm, and he ventured to plant both his feet upon it. But, alas! he has forgotten how slippery a flag of slate, polished by two hundred years' exposure to the elements, may become. His feet slipped from under him, and in striving to save himself he overbalanced the stone. Instantly it revolved, and a second later he found himself suspended over the well, with only the strength of a despairing grasp on the edges of the slate between him and eternity. CHAPTER XXXIII THE SECRET OF THE DOOR Miss Fitzgerald's disclosures to the Marchioness, as it turned out, rather helped than hindered those principally concerned, for Mr. Lambert met her Ladyship at the church, and his explanations took the keen edge off the wrath which she vented on her daughter a little later, and in the midst of which Lieutenant Kingsland arrived, with ample assurances of worldly prosperity, which overcame her strongest objections, and went far to reconcile her to the inevitable. Her disappointment, however, was keen, and her temper suffered in consequence, so that dinner, at which the Secretary's unaccountable absence formed the chief topic of conversation, was distinctly not a success, and the ladies retired early, leaving the gentlemen to their own devices. Miss Fitzgerald claimed to join in the general hegira, but her actions belied her words, for shortly after she was supposed to have gone to her room, her figure, its white dinner dress concealed by a long grey cloak, might have been seen gliding across the lawn in the direction of the inn. The night was pregnant with great events, though outwardly calm and beautiful, and the great hall in which Mr. Riddle, Kent-Lauriston, and the Lieutenant stood smoking, after having been dismissed from the drawing-room, was flooded with moonlight. "I say," remarked Kingsland irrelevantly, after a long interval broken only by the conscientious puffing of cigarettes, "how that mediæval prize puzzle shows up in the moonlight." "The secret door?" asked Kent-Lauriston. "Yes, it does. I heard the butler making his plaint about it yesterday. It appears it's no joke to keep those nails polished." "I shouldn't think it would be, and I dare say the bulk of the servants wouldn't touch it with a ten-foot pole. I wonder what's behind it, anyway." Nobody said anything.