At last, when the full moon was shining, the two men stood at the head of the rapids and surveyed their surroundings before setting out on their return to camp.

Both sides of the Xingu were lined by the dense forest, in which the vegetation is so luxuriant that it must be a source of never ending wonder to those who look upon it for the first time. The river above made a sharp bend, shutting off the view so fully that from their position, it was impossible to tell how far they would be able to use the canoe without making another portage.

"We haven't seen a person on our way here," remarked the Professor, calmly surveying the river and shores; "and I hope Ashman will bring back a similar report, for we all need a full night's rest."

"How is that?"

Long touched the arm of his companion, as he asked the question, and pointed down stream in the direction of camp.

To the amazement of the Professor, three natives were seen standing on the very spot where they themselves had stood a brief while before, evidently scrutinizing the white strangers with profound wonder and curiosity.

They were dressed similarly to Bippo, Pedros and Quincal—that is, with only a piece of cloth around the loins—but they displayed a marked contrast in other respects. They were taller, more athletic, with immense bushy heads of hair, enormous rings in their ears, while the hue of their skins was almost as dark as that of the native African.

One carried a long-bow and a bundle of arrows strapped behind his shoulders, while the others were armed simply with javelins or spears.

"Those fellows mean fight," added Long.

"No doubt of it," replied the Professor.

"But a Winchester will reach further than their arrows and spears, even if they are tipped with poison."

"Possibly they may be friendly, if they can be convinced that we intend them no harm, and you know what an advantage it will be to us if able to trust all the natives on our return."

Long could not share the confidence of his companion and favored a direct advance down the bank toward the savages. If the latter preserved their armed neutrality, all would be well enough, but at the first sign of hostility he advocated opening fire on them.

Perhaps he was right in the declaration that anything like timidity in dealing with savages is the worst possible course. While the rights of every barbarian should be respected, it is all important that he should know that such concession is made not through fear, but because the superior party wishes to be just and merciful.

The natives stood as motionless as statues for several minutes, during which the white men scrutinized them with an interest that may be imagined.

The first and most natural thought of our friends was that an encounter could be avoided by entering the forest on the right and passing round the savages, who, it was quite apparent, intended to dispute their return; but if such was really their purpose, they would have little trouble in heading off the whites in the dense wood, beside which, for the weighty reasons already named, it would have been exceedingly unwise to act as though afraid of the dusky natives.

Despite Long's protest, the Professor decided to make a friendly advance, being vigilantly on his guard at the same time for the first offensive move of the savages. He carried his Winchester in one hand, while he rested the other on his revolver. He was determined, while hoping for comity, to be prepared for hostility or treachery.

Long was so dissatisfied with the looks of things, that he followed his friend a few paces, then halting with his Winchester ready for any emergency, and certain in his own mind that a sharp fight was inevitable.

The approach of the white man was evidently a surprise to the savages. The middle one, who held the long-bow and arrows, fell back several paces, as if about to break into flight or dart among the trees so invitingly near, but something must have been said by his companions to check him, for he stopped abruptly, and not only came back to his first position, but advanced a couple of paces beyond. The noise from the rapids prevented the Professor hearing their voices, though the unusually clear moonlight told him that some utterance had passed between them.

The first ominous act on the part of the natives was by this archer, who deliberately drew an arrow from over his shoulder and fitted it against the string of his bow. The fact that the missile was undoubtedly coated at the end with a virus more deadly than that of the rattlesnake or cobra was enough to render the would-be friend uncomfortable and to increase his alertness.

At the same time that the archer went through this significant preliminary, his companions shifted their grasp upon their javelins in a manner that was equally suggestive.

While carrying these primitive weapons, the fingers closed around the centre of gravity, that naturally being more convenient, but when about to hurl them, the hand was shoved further toward the head. Both natives thus shifted their right hands, though, they still held them horizontal at their thighs, from which position they could be brought aloft in the twinkling of an eye.

The white man walked slowly. The left hand, which supported his rifle, remained motionless, but removing the right from his revolver, he continued making signs, whose friendly meaning was so obvious that it was impossible for the natives to mistake it.

While approaching in this guarded manner, he Studied them with the closest scrutiny. Interesting under any circumstances, they were vastly more so at this time. What struck him in addition to the characteristics already named, were their frowsy eyebrows and glittering coal-black eyes. These were unusually large and protruding. The noses, instead of being broad and flat, like those of the native Africans, were Roman in shape. The mouths were wide, and, when they spoke, he observed that the teeth which were displayed were black, showing that a fashion prevailed among this unknown tribe similar to that in vogue among many of the natives in the East Indies.

Now, Professor Grimcke was too experienced an explorer to walk directly into danger, where there was no prospect of avoiding a desperate encounter. While eager to make friends with all the people whom he met, he did not intend to assume any unnecessary risks. The demeanor of the natives tendered it certain they were hostile. They made no responsive signs to those of the white man, and the latter would have checked himself half way, but for his suspicion that they were mystified by his conduct and were undecided as to the precise thing to do.

He not only heard their peculiar rumbling voices, but saw from the movements of their lips and their glances in each other's faces, that they were consulting as to what they should do. The white man was already so close that he could easily be reached by the bowman, and there was little doubt that either of the others could hurl his poisoned javelin the intervening distance.

The only way of defeating such a movement was for the white man to secure "the drop" on them, but, in one sense that was impossible. Unable to understand the words spoken, they were equally unacquainted with the weapons of the pale face, and would, doubtless pay no heed to the most threatening demonstration on his part.

"Take my advice and come back," called Jared Long; "keep your face toward them and blaze away, and I'll do my part!"

Instead of adopting the suggestion of his friend, the Professor slowed his pace, still making his gestures of good will. However, when fifty steps away, he came to a dead halt.

He had advanced three-fourths the distance, and, if the others were willing to accept his offers, they should signify it by coming forward and meeting him where he had stopped.

While moving forward in this guarded manner, Grimcke was prudent enough to edge over toward the woods, which were now so close to his right side as to be instantly available. When he came to a stop also it was near the trunk of a large tree, no more than a yard distant.

"The Professor is cunning," reflected Jared Long, watching every movement; "he'll whisk behind the tree the instant one of them makes a move. Helloa! what's up now?"

To the astonishment of both white men the native with the bow shifted it at this moment to his right hand, holding the arrow in place against the string with the same hand, while the weapon was at his side. Then he moved a step or two, as if to meet the stranger.

"Look out!" called the vigilant New Englander, "that chap is up to some deviltry."

He did not refer to him with the bow and arrow, but to one of the others, who stealthily turned aside and vanished among the trees. Being in the Professor's line of vision the latter observed the suspicious movement, and it cannot be said that it added to his comfort.

Meanwhile the archer advanced, but with such tardy step that it was evident he was timing his pace to that of his comrade who had so stealthily entered the wood. Convinced that his real peril lay among those trees, Grimcke began a backward movement with such caution that he hoped it would not be noticed by the native who was approaching with a sluggish pace.

The forest, like all those in South America, was so dense that great care was necessary for one to pick his way through it. The Professor's theory was that the savage with the spear would regulate his movements on the theory that the white man would not stir from the place where he had first halted. He would thus aim to secure a position from which he could hurl his javelin at him without detection. Grimcke conceived this was certain to take place, and, if he remained where he was, nothing could save him from the treacherous assault. It was a matter, therefore, of self preservation that dictated the brief retreat with the hope of thus disconcerting the savage.

The task which Grimcke had given himself was difficult indeed. The ground was unfavorable for the peculiar twitching movement which he hoped would carry him out of danger. He had gone barely a couple of yards when the bowman evidently suspected something of the kind, for he stopped short and stared inquiringly at the white man.

The latter extended his right hand as if to shake that of the savage, who stood motionless, making no sign of pleasure or displeasure. Indeed, he remained so fixed in his position that Grimcke was convinced he was listening for the sound of the other miscreant stealing through the wood. He plainly saw the black eyes cast a single inquiring glance in that direction.

"This is getting a little too threatening," reflected the Professor, satisfied that the three natives were as venomous as so many serpents; "at the first move war is declared."

His situation was so critical that he did not dare turn his head to look behind him, but never was there a more welcome sound to him than that made by the footsteps of the lank New Englander.

"Keep moving hack!" called Long, "but don't try to hide what you're doing."

The Professor saw the sense of this advice and he followed it, lifting his feet so high that the action was plainly seen, but doing so with a certain dignity that was not lacking in impressiveness. His aim was to give the act the appearance of a strategic movement, as it may be called. It was not that he was afraid of the natives, but he was seeking a better place from which to open hostilities against them.

This was the impression which he sought to give the fierce savages, and whether he succeeded, or not was certain to become apparent within the following five minutes. He himself believed, the chances were against the success of his plan.