Waiting in ambush was by no means new to him. He was not in the least troubled by impatience. To be sure, he would have felt more comfortable with a piece of bread and a cup of water; yet deprivations of the kind were within the expectations; and while there was a hope of good issue for the enterprise, he could endure them indefinitely. The charge given him pertained particularly to Demedes. No fear of his not recognizing the Greek. Had he not enjoyed the delight of holding him out over the wall to be dropped to death?

He was eager, but not impatient. His chief dependence was in the sense of feeling, which had been cultivated so the slightest vibration along the ground served him in lieu of hearing. The closing of the front door by the keeper--felt, not heard--apprised him the day was over.

Not long afterward the pavement was again jarred, bringing a return of the sensations he used to have when, stalking lions in Kash-Cush, he felt the earth thrill under the galloping of the camelopards stampeded.

He drew the curtain aside slightly, just as a man stepped into the court from the passage. The person carried a lighted lamp, and was not Demedes.

The cistern-keeper--for he it was--went to the curbing slowly, for the advance airs of the gale were threatening his lamp, and dropped dextrously through the aperture to the upper landing.

In ambush the King never admitted anything like curiosity. Presently he felt the pavement again jar. Nobody appeared at the passage. Another tremor more decided--then the King stepped softly from the sedan, and stealing barefooted to the curbing looked down the yawning hole.

The lamp on the platform enabled him to see a boat drawn up to the lower step, and the stranger in the act of stepping into it. Then the lamp was shifted to the bow of the boat--oars taken in hand--a push off, and swift evanishment.

We, with our better information of the devices employed, know what a simple trick it was on the keeper's part to bring the vessel to him--he had but to pull the right string in the right direction--but Nilo was left to his astonishment. Stealing back to his cover, he drew the door to, and struggled with the mystery.

Afterwhile, the mist dissipated, and a fact arose plainer to him than the mighty hand on his knee. The cistern was inhabited--some person was down there to be communicated with. What should the King do now?

The quandary was trying. Finally he concluded to stay where he was. The stranger might bring somebody back with him--possibly the lost child--such Lael was in his thoughts of her.

Afterwhile--he had no idea of time--he felt a shake run along the pavement, and saw the stranger appear coming up the steps, lamp in hand. Next instant the person crawled out of the curbing, and went into the house through the passage doorway. The King never took eye from the curbing--nobody followed after--the secret of the old reservatory was yet a secret.

Again Nilo debated whether to bring Sergius in, and again he decided to stay where he was.

Meantime the cloud which the Prince of India had descried from the roof of his house arrived on the wings of the gale. Ere long Sergius was shivering in the recess of the door. For relief he counted the beads of his rosary, and there was scarcely a Saint in the calendar omitted from his recitals. If there was potency in prayers the angels were in the cistern ministering to Lael.

The street became deserted. Everything living which had a refuge sought it; yet the gale increased: it howled and sang dirges; it started the innumerable loose trifles in its way to waltzing over the bowlders; every hinged fixture on the exposed house-fronts creaked and banged. Only a lover would voluntarily endure the outdoors of such a night--a lover or a villain unusually bold.

Near midnight--so Sergius judged--a dull redness began to tinge the cloud overhead, and brightening rapidly, it ere long cast a strong reflection downward. At first he was grateful for the light; afterwhile, however, he detected an uproar distinguishable from the wind; it had no rest or lulls, and in its rise became more and more a human tone. When shortly people rushed past his cover crying fire, he comprehended what it was. The illumination intensified. The whole city seemed in danger. There were women and children exposed; yet here he was waiting on a mere hope; there he could do something. Why not go?

While he debated, down the street from the direction of the Hippodrome he beheld a man coming fast despite the strength of the gusts. A cloak wrapped him from head to foot, somewhat after the fashion of a toga, and the face was buried in its folds; yet the air and manner suggested Demedes. Instantly the watcher quit arguing; and forgetful of the fire, and of the city in danger, he shrank closer into the recess.

The thoroughfare was wider than common, and the person approaching on the side opposite Sergius; when nearer, his low stature was observable. Would he stop at the cistern-keeper's?

Now he was at the door!

The Russian's heart was in his mouth.

Right in front of the door the man halted and knocked. The sound was so sharp a stone must have been used. Immediately the bolt inside was drawn, and the visitor passed in.

Was it Demedes? The monk breathed again--he believed it was--anyhow the King would determine the question, and there was nothing to do meantime but bide the event.

The sedan, it hardly requires saying, was a much more comfortable ambush than the recess of the door. Nilo merely felt the shaking the gale now and then gave the house. So, too, he bade welcome to the glare in the sky for the flushing it transmitted to the court. Only a wraith could have come from or gone into the cistern unseen by him.

The clapping to of the front door on the street was not lost to the King. Presently the person he had seen in the boat at the foot of the steps again issued from the passage, lamp in hand as before; but as he kept looking back deferentially, a gust leaped down, and extinguished the flame, compelling him to return; whereupon another man stepped out into the court, halting immediately. Nilo opened a little wider the gap in the curtain through which he was peeping.

It may be well to say here that the newcomer thus unwittingly exposing himself to observation was the same individual Sergius had seen admitted into the house. The keeper had taken him to a room for the rearrangement of his attire. Standing forth in the light now filling the court, he was still wrapped in the cloak, all except the head, which was jauntily covered with a white cap, in style not unlike a Scotch bonnet, garnished with two long red ostrich feathers held in place by a brooch that shot forth gleams of precious stones in artful arrangement. Once the man opened the cloak, exposing a vest of fine-linked mail, white with silver washing, and furnished with epaulettes or triangular plates, fitted gracefully to the shoulders. A ruff, which was but the complement of a cape of heavy lace, clothed the neck.

To call the feeling which now shot through the King's every fibre a sudden pleasure would scarcely be a sufficient description; it was rather the delight with which soldiers old in war acknowledge the presence of their foemen. In other words, the brave black recognized Demedes, and was strong minded enough to understand and appreciate the circumstances under which the discovery was made. If the savage arose in him, it should be remembered he was there to revenge a master's wrongs quite as much as to rescue a stolen girl. Moreover, the education he had received from his master was not in the direction of mercy to enemies.

The two--Demedes and the keeper--lost no time in entering the cistern, the latter going first. When the King thought they had reached the lower platform, he issued from the chair barefooted, and bending over the curbing beheld what went on below.

The Greek was holding the lamp. The occupation of his assistant was beyond comprehension until the boat moved slowly into view. Demedes then set the lamp down, divested himself of his heavy wrap, and taking the rower's seat, unshipped the oars. There was a brief conference; at the conclusion the subordinate joined his chief; whereupon the boat pushed off.

Thus far the affair was singularly in the line of Sergius' anticipations; and now to call him in!

There is little room for doubt that Nilo was in perfect recollection of the instructions he had received, and that his first intention was to obey them; for, standing by the curbing long enough to be assured the Greek was indeed in the gloomy cavern, whence escape was impossible except by some unknown exit, he walked slowly away, and was in the passage door when, looking back, he saw the keeper leaping out into the court.

To say truth, the King had witnessed the departure of the boat with misgivings. Catching the robbers was then easy; yet rescue of the girl was a different thing. What might they not do with her in the meantime? As he understood his master, her safety was even more in purpose than their seizure; wherefore his impulse was to keep them in sight without reference to Sergius. He could swim--yes, but the water was cold, and the darkness terrible to his imagination. It might be hours before he found the hiding-place of the thieves--indeed, he might never overtake them. His regret when he stepped into the passage was mighty; it enables us, however, to comprehend the rush of impetuous joy which now took possession of him. A step to the right, and he was behind the cheek of the door.

All unsuspicious of danger, the keeper came on; a few minutes, and he would be in bed and asleep, so easy was he in conscience. The ancient cistern had many secrets. What did another one matter? His foot was on the lintel--he heard a rustle close at his side--before he could dart back--ere he could look or scream, two powerful hands were around his throat. He was not devoid of courage or strength, and resisted, struggling for breath. He merely succeeded in drawing his assailant out into the light far enough to get a glimpse of a giant and a face black and horrible to behold. A goblin from the cistern! And with this idea, he quit fighting, and sank to the floor. Nilo kept his grip needlessly--the fellow was dead of terror.

Here was a contingency not provided for in the arrangement Sergius had laid out with such care.

And what now?

It was for the King to answer.