a few minutes after passing the bend in the stream, which hid the rock and the sleeping sentinel from sight, fred ashman observed that the smooth current broadened into a lake, forming the extraordinary sheet of water of which he had heard such strange accounts.

he held the paddle suspended, and looked around.

the surface was as calm as the face of a mirror, and in the strong moonlight, as he looked down he could see that it was of crystalline clearness—so much so, indeed, that a boat or any floating object looked as if suspended in mid-air.

it expanded right and left and in front, until he could barely discern the dim outlines of trees and rocks that shut it in. it was probably two or three square miles in extent, and to the westward the shore appeared to be composed of enormous boulders and masses of rocks.

directly ahead, was a crag more massive than the rest, towering a hundred feet above the lake, with a breadth fully one half as great. it resembled some gigantic sentinel, keeping ward and watch over the strange region unknown to few if any white man.

ashman turned to his companion with the question, what course he should take, and, without speaking, she pointed to the rock which she saw had attracted his attention.

very slight effort was required to propel the delicate craft, which seemed to become sentient, and to move forward in obedience to the wishes of its occupants. he barely dipped the blade into the water, when it skimmed forward like a swallow. after a number of strokes he ceased and fixed his eyes on the landmark by which he was proceeding.

a singular emotion held him speechless for the time. the vast mass of stone appeared to be slowly rising from the bosom of the lake, and, instead of remaining motionless, was advancing to meet the tiny canoe and its awed occupants. one moment, it was like some vast ogre, stealing silently about to crush them beneath the clear waters, and then it became a friendly giant, reaching out its hand to lead them forward.

but for the distant sounds of firing at the murhapa village, fred ashman would have felt that it was all a vision of sleep, from which he must soon awake to the realities of life.

but that horrible, grinding discord continually creeping into their ears told too plainly the dreadful scenes at comparatively a short distance. even in his exalted mental state, ashman began to ask himself what was to be the end of the strange venture upon which he had started. a disquieting misgiving arose, that perhaps he had not done the wisest thing in leaving his imperilled friends.

but he reflected that he had only obeyed the orders of ziffak, who indeed would not have permitted his wishes to be disregarded, for who should know the wisest course so well as he? besides, his own reason told him that if the professor and his companion were attacked in the cabin, it was impossible for him to raise a finger in their behalf.

and so he dismissed that phase of the marvellous business from his mind and faced the present situation.

he had fled with ariel from her father, king haffgo. instead of turning to the northward down the xingu, they had gone further up the stream and directly away from the right course out of the perilous country.

but while, in one sense, this might be looked upon as the height of recklessness, he saw it was unavoidable. had they turned down the xingu, there would have been no escaping their foes, while the enchanted lake and its surroundings must afford secure shelter for a time.

but for how long?

that was the question which obtruded itself, even while filled with the delightful thrill of his new love, and when en rapport with his marvellous surroundings.

the intimate knowledge which ariel possessed of the region would guide them to some spot where they could reasonably hope to be safe from pursuit, unless such pursuit was led by her enraged parent.

ashman was still scrutinizing the great mass of rock, steadily assuming more definite shape in the moonlight as the intervening distance decreased, when he was surprised that he had not noticed the mountainous elevation behind it. the immense rock seemed but the beginning of others rising beyond to the height of a thousand feet, while they broadened to the right and left until they stretched over an extent of several miles.

it seemed to him that these constituted a spur of the geral range, which extend in a northwesterly direction between the guapore river (forming a part of the eastern boundary of bolivia) and the headwaters of the tapajos and xingu. if so, their extent was continuous for a hundred miles.

ashman had ceased paddling, though, under the faint momentum remaining, the canoe continued slowly moving over the lake and gradually drawing near the rock. he did not break the silence, but asked himself what could be the reason of ariel's direction for him to paddle toward the rock. he supposed there was some place of concealment which she had in mind, though he discerned nothing of that nature.

"we cannot stay there forever," was the practical thought in the mind of the lover, who felt the next moment as though he would be happy to dwell forever anywhere with her.

"after we have staid here until pursuit is given up—if it ever will be—then we must leave the country. i will take her to my home in north america, where i shall love and cherish her and become the envied of all men."

"we are approaching the rock," he said, addressing her; "what next, dearest ariel."

"paddle right on," was the astonishing reply.

he looked at her with a questioning smile. could she be in earnest?

"right on," she repeated, reading his thoughts aright.

"very well; the slave obeys his mistress," he replied, giving the paddle another dip in the water.

gazing ahead, he instantly discovered the cause of her reply. a tunnel opened into the rock, seemingly near the centre. it was perhaps ten feet in height and with a width slightly greater. could it be she meant he should enter that black forbidding passage? he asked the question and she replied that such was her wish.

he could not decline to take her whither she desired to go. gently swaying the blade, he sent the boat within the dark opening, which appeared to distend its jaws to swallow the canoe and them from the world to which they had bidden good-bye.

ashman was beginning to ask himself how he was to continue the advance in the darkness, which must become impenetrable as they passed beyond the limit of the moonlight, when he perceived the water into which he dipped the paddle.

not only that, but it grew more distinct as he progressed, until once more the form of his beloved came out to view, as she sat near him in the canoe.

wondering what it all meant, he gazed ahead. the surface of the water grew plainer, as his eye ranged along the tunnel, until, only a short distance away, the view was clearer than on the lake itself, beneath the full moon.

what was the explanation of this wonderful sea of illumination into which he was guiding the canoe?