There were no roads or beaten paths in this secluded portion of the royal domain, neither could there be seen any traces of habitation. "Deep in yonder lake," said Omar, drawing up his horse suddenly and swinging himself from his saddle near the spot where the waters, springing from beneath some green, moss-grown rocks, fell with gentle music into the river--"deep in yonder lake there lies a hidden mystery." "A mystery!" I cried. "What is it?" "Have patience, and I will reveal to you a secret known only to myself and to the Naya; the secret that I told you must be preserved." "But you say it is buried beneath these waters!" I exclaimed, puzzled. "How will you reveal it?" "Watch closely, so that if occasion arises you will remember how to exactly imitate my movements," he answered, and when we had tethered our horses, he led me away from the edge of the lake up the hill-side some distance to where a number of points of moss-grown rock cropped up out of the turf. After searching among them for some minutes he suddenly stopped before one that rose from the ground about three feet and was perhaps ten yards in circumference, examining it carefully, at last giving vent to an ejaculation of satisfaction. "You see this rock, Scars!" he cried. "Does anything about it appear to you remarkable?" I bent, and feeling it with both my hands, carefully examined its side, top and base. "No," I answered, laughing. "As far as I can detect it is the same as the others." "You would never guess anything hidden there?" he asked, smiling. "No." "Well, watch and I'll show you." And with these words the Naba of Mo approached the rock at a point immediately facing me, and placing his hands upon the side, about two feet from the ground, drew out bodily a portion of its lichen-covered face about eighteen inches square, that had been so deftly hewn that when in its place none could detect it had ever been removed. Peering into the cavity thus disclosed I saw, to my surprise, what appeared to be a small iron lever, thickly rusted, descending into some cog-wheeled mechanism of a very complicated character. "Now, watch the lake while I reveal to you its mystery," my companion said, placing his hands upon the lever. With a harsh, grating noise it fell back beneath the weight he threw upon it, and the harsh jarring of cog-wheels revolving sounded for a few moments beneath our feet. Then, as he set the mechanism in motion, my gaze was fixed upon the lake and I stood aghast in wonderment.