Von Horn cursed the chance that had snatched the girlfrom him, but he tried to content himself with thethought that the treasure probably still rested in thecabin of the Ithaca, where Bududreen was to havedeposited it. He wished that the Dyaks would takethemselves off so that he could board the vessel andcarry the chest ashore to bury it against the time thatfate should provide a means for transporting it to Singapore.

In the water below him floated the Ithaca's masts,their grisly burdens still lashed to their wave sweptsides. Bududreen lay there, his contorted features setin a horrible grimace of death which grinned up at theman he would have cheated, as though conscious of thefact that the white man would have betrayed him had theopportunity come, the while he enjoyed in anticipationthe other's disappointment in the loss of both the girland the treasure.

The tide was rising now, and presently the Ithaca beganto float. No sooner was it apparent that she was freethan the Dyaks sprang into the water and swam to herside. Like monkeys they scrambled aboard, swarmingbelow deck in search, thought von Horn, of pillage.He prayed that they would not discover the chest.

Presently a half dozen of them leaped overboard andswam to the mass of tangled spars and rigging whichlittered the beach. Selecting what they wished theyreturned to the vessel, and a few minutes later vonHorn was chagrined to see them stepping a jury mast--he thought the treasure lay in the Ithaca's cabin.

Before dark the vessel moved slowly out of the harbor,setting a course across the strait in the directionthat the war prahus had taken. When it was apparentthat there was no danger that the head hunters wouldreturn, the lascar came from his hiding place, anddancing up and down upon the shore screamed warlikechallenges and taunts at the retreating enemy.

Von Horn also came forth, much to the sailor'ssurprise, and in silence the two stood watching thedisappearing ship. At length they turned and madetheir way up the stream toward camp--there was nolonger aught to fear there. Von Horn wondered if thecreatures he had loosed upon Professor Maxon had donetheir work before they left, or if they had all turnedto mush as had Number Thirteen.

Once at the encampment his questions were answered,for he saw a light in the bungalow, and as he mountedthe steps there were Sing and Professor Maxon justcoming from the living room.

"Von Horn!" exclaimed the professor. "You, then, are not dead;but where is Virginia? Tell me that she is safe."

"She has been carried away" was the startling answer."Your creatures, under the thing you wished to marryher to, have taken her to Borneo with a band of Malayand Dyak pirates. I was alone and could do nothing toprevent them."

"God!" moaned the old man. "Why did I not kill the thingwhen it stood within my power to do so. Only last nighthe was here beside me, and now it is too late."

"I warned you," said von Horn, coldly.

"I was mad," retorted the professor. "Could you notsee that I was mad? Oh, why did you not stop me?You were sane enough. You at least might have forcedme to abandon the insane obsession which has overpoweredmy reason for all these terrible months. I am sane now,but it is too late--too late."

"Both you and your daughter could only have interpretedany such action on my part as instigated by self-interest, for you both knew that I wanted to makeher my wife," replied the other. "My hands were tied.I am sorry now that I did not act, but you can readilysee the position in which I was placed."

"Can nothing be done to get her back?" cried the father."There must be some way to save her. Do it von Horn,and not only is my daughter yours but my wealth as well--every thing that I possess shall be yours if you willbut save her from those frightful creatures."

"The Ithaca is gone, too," replied the doctor. "Thereis only a small boat that I hid in the jungle for somesuch emergency. It will carry us to Borneo, but whatcan we four do against five hundred pirates and thedozen monsters you have brought into the world?No, Professor Maxon, I fear there is little hope,though I am willing to give my life in an attemptto save Virginia. You will not forget your promiseshould we succeed?"

"No, doctor," replied the old man. "I swear that youshall have Virginia as your wife, and all my propertyshall be made over to you if she is rescued."

Sing Lee had been a silent listener to this strangeconversation. An odd look came into his slant eyesas he heard von Horn exact a confirmation fromthe professor, but what passed in his shrewd mindonly he could say.

It was too late to attempt to make a start that day for Borneo,as darkness had already fallen. Professor Maxon and von Hornwalked over to the workshop and the inner campong to ascertainwhat damage had been done there.

On their return Sing was setting the table on theverandah for the evening meal. The two men were talking,and without making his presence noticeable the Chinamanhovered about ever within ear shot.

"I cannot make it out, von Horn," Professor Maxon wassaying. "Not a board broken, and the doors bothapparently opened intentionally by someone familiarwith locks and bolts. Who could have done it?"

"You forget Number Thirteen," suggested the doctor.

"But the chest!" expostulated the other. "What in theworld would he want of that enormous and heavy chest?"

"He might have thought that it contained treasure,"hazarded von Horn, in an innocent tone of voice.

"Bosh, my dear man," replied Professor Maxon. "He knewnothing of treasures, or money, or the need or value of either.I tell you the workshop was opened, and the inner campongas well by some one who knew the value of money and wantedthat chest, but why they should have released the creaturesfrom the inner enclosure is beyond me."

"And I tell you Professor Maxon that it could have beennone other than Number Thirteen," insisted von Horn."Did I not myself see him leading his eleven monstersas easily as a captain commands his company? The fellowis brighter than we have imagined. He has learned muchfrom us both, he has reasoned, and he has shrewdlyguessed many things that he could not have knownthrough experience."

"But his object?" asked the professor.

"That is simple," returned von Horn. "You have heldout hopes to him that soon he should come to live underyour roof with Virginia. The creature has been madlyinfatuated with her ever since the day he took her fromNumber One, and you have encouraged his infatuationuntil yesterday. Then you regained your sanityand put him in his rightful place. What is the result?Denied the easy prey he expected he immediately decidedto take it by force, and with that end in view, and takingadvantage of the series of remarkable circumstanceswhich played into his hands, he liberated his fellows,and with them hastened to the beach in search ofVirginia and in hopes of being able to fly with herupon the Ithaca. There he met the Malay pirates,and together they formed an alliance under termsof which Number Thirteen is to have the girl, and the piratesthe chest in return for transporting him and his crew to Borneo.Why it is all perfectly simple and logical, Professor Maxon;do you not see it now?"

"You may be right, doctor," answered the old man."But it is idle to conjecture. Tomorrow we can be upand doing, so let us get what sleep we can tonight.We shall need all our energies if we are to save my poor,dear girl, from the clutches of that horrid, soulless thing."

At the very moment that he spoke the object of hiscontumely was entering the dark mouth of a broad riverthat flowed from out of the heart of savage Borneo.In the prahu with him his eleven hideous companions nowbent to their paddles with slightly increased efficiency.Before them the leader saw a fire blazing upon a tiny islandin the center of the stream. Toward this they turnedtheir silent way. Grimly the war prahu with its frightfulfreight nosed closer to the bank.

At last Number Thirteen made out the figures of menabout the fire, and as they came still closer he wassure that they were members of the very party he hadbeen pursuing across the broad waters for hours.The prahus were drawn up upon the bank and the warriorswere preparing to eat.

Just as the young giants' prahu came within the circleof firelight a swarthy Malay approached the fire,dragging a white girl roughly by the arm. No more wasneeded to convince Number Thirteen of the identity ofthe party. With a low command to his fellows he urgedthem to redoubled speed. At the same instant a Dyakwarrior caught sight of the approaching boat as it spedinto the full glare of the light.

At sight of the occupants the head hunters scatteredfor their own prahus. The frightful aspect ofthe enemy turned their savage hearts to water,leaving no fight in their ordinarily warlike souls.

So quickly they moved that as the pursuing prahutouched the bank all the nearer boats had beenlaunched, and the remaining pirates were scurryingacross the little island for those which lay upon theopposite side. Among these was the Malay who guardedthe girl, but he had not been quick enough to preventVirginia Maxon recognizing the stalwart figure standingin the bow of the oncoming craft.

As he dragged her away toward the prahu of Muda Saffirshe cried out to the strange white man who seemed herself-appointed protector.

"Help! Help!" she called. "This way! Across the island!"And then the brown hand of her jailer closed over her mouth.Like a tigress she fought to free herself, or to detainher captor until the rescue party should catch up with them,but the scoundrel was muscled like a bull, and when the girlheld back he lifted her across his shoulder and broke into a run.

Rajah Muda Saffir had no stomach for a fight himself,but he was loathe to lose the prize he had but just won,and seeing that his men were panic-stricken he sawno alternative but to rally them for a brief standthat would give the little moment required to slip awayin his own prahu with the girl.

Calling aloud for those around him to come to hissupport he halted fifty yards from his boat just asNumber Thirteen with his fierce, brainless horde sweptup from the opposite side of the island in the wake ofhim who bore Virginia Maxon. The old rajah succeededin gathering some fifty warriors about him from thecrews of the two boats which lay near his. His own menhe hastened to their posts in his prahu that they mightbe ready to pull swiftly away the moment that he andthe captive were aboard.

The Dyak warriors presented an awe inspiringspectacle in the fitful light of the nearby camp fire.The ferocity of their fierce faces was accentuatedby the upturned, bristling tiger cat's teeth whichprotruded from every ear; while the long feathersof the Argus pheasant waving from their war-caps,the brilliant colors of their war-coats trimmedwith the black and white feathers of the hornbill,and the strange devices upon their gaudy shieldsbut added to the savagery of their appearanceas they danced and howled, menacing and intimidating,in the path of the charging foe.

A single backward glance was all that Virginia Maxonfound it possible to throw in the direction of therescue party, and in that she saw a sight that livedforever in her memory. At the head of his hideous,misshapen pack sprang the stalwart young giantstraight into the heart of the flashing parangsof the howling savages. To right and left fellthe mighty bull whip cutting down men with allthe force and dispatch of a steel saber.The Dyaks, encouraged by the presence of Muda Saffirin their rear, held their ground; and the infuriated,brainless things that followed the wielder of thebull whip threw themselves upon the head hunterswith beating hands and rending fangs.

Number Ten wrested a parang from an adversary,and acting upon his example the other creatureswere not long in arming themselves in a similar manner.Cutting and jabbing they hewed their way through the solidranks of the enemy, until Muda Saffir, seeing that defeatwas inevitable turned and fled toward his prahu.

Four of his creatures lay dead as the last of the Dyaksturned to escape from the mad white man who facednaked steel with only a rawhide whip. In panic the headhunters made a wild dash for the two remaining prahus,for Muda Saffir had succeeded in getting away from theisland in safety.

Number Thirteen reached the water's edge but a momentafter the prow of the rajah's craft had cleared theshore and was swinging up stream under the vigorousstrokes of its fifty oarsmen. For an instant he stoodpoised upon the bank as though to spring after theretreating prahu, but the knowledge that he could notswim held him back--it was useless to throw away hislife when the need of it was so great if Virginia Maxonwas to be saved.

Turning to the other prahus he saw that one was alreadylaunched, but that the crew of the other was engaged ina desperate battle with the seven remaining members ofhis crew for possession of the boat. Leaping among thecombatants he urged his fellows aboard the prahu whichwas already half filled with Dyaks. Then he shoved theboat out into the river, jumping aboard himself as itsprow cleared the gravelly beach.

For several minutes that long, hollowed log was averitable floating hell of savage, screaming men lockedin deadly battle. The sharp parangs of the headhunters were no match for the superhuman muscles of thecreatures that battered them about; now lifting onehigh above his fellows and using the body as a club tobeat down those nearby; again snapping an arm or leg asone might break a pipe stem; or hurling a livingantagonist headlong above the heads of his fellows tothe dark waters of the river. And above them all inthe thickest of the fight, towering even above his owngiants, rose the mighty figure of the terrible whiteman, whose very presence wrought havoc with the valorof the brown warriors.

Two more of Number Thirteen's creatures had been cutdown in the prahu, but the loss among the Dyaks hadbeen infinitely greater, and to it was now added thedesertions of the terror stricken savages who seemedto fear the frightful countenances of their adversarieseven as much as they did their prowess.

There remained but a handful of brown warriors in oneend of the boat when the advantage of utilizing theirknowledge of the river and of navigation occurred toNumber Thirteen. Calling to his men he commanded themto cease killing, making prisoners of those whoremained instead. So accustomed had his pack nowbecome to receiving and acting upon his orders thatthey changed their tactics immediately, and one by onethe remaining Dyaks were overpowered, disarmed and held.

With difficulty Number Thirteen communicated with them,for among them there was but a single warrior who hadever had intercourse with an Englishman, but at last bymeans of signs and the few words that were common tothem both he made the native understand that he wouldspare the lives of himself and his companions if theywould help him in pursuit of Muda Saffir and the girl.

The Dyaks felt but little loyalty for the rascallyMalay they served, since in common with all their kindthey and theirs had suffered for generations at thehands of the cruel, crafty and unscrupulous race thathad usurped the administration of their land. So itwas not difficult to secure from them the promise ofassistance in return for their lives.

Number Thirteen noticed that when they addressed himit was always as Bulan, and upon questioning them hediscovered that they had given him this title of honorpartly in view of his wonderful fighting ability andpartly because the sight of his white face emergingfrom out of the darkness of the river into thefirelight of their blazing camp fire had carried totheir impressionable minds a suggestion of the tropicmoon which they admired and reverenced. Both the nameand the idea appealed to Number Thirteen and from thattime he adopted Bulan as his rightful cognomen.

The loss of time resulting from the fight in the prahuand the ensuing peace parley permitted Muda Saffirto put considerable distance between himself andhis pursuers. The Malay's boat was now alone, forof the eight prahus that remained of the original fleetit was the only one which had taken this branch of the river,the others having scurried into a smaller southerly armafter the fight upon the island, that they might themore easily escape their hideous foemen.

Only Barunda, the headman, knew which channel RajahMuda Saffir intended following, and Muda wondered whyit was that the two boats that were to have borneBarunda's men did not catch up with his. While he hadleft Barunda and his warriors engaged in battle withthe strangers he did not for an instant imagine thatthey would suffer any severe loss, and that one oftheir boats should be captured was beyond belief.But this was precisely what had happened, and thesecond boat, seeing the direction taken by the enemy,had turned down stream the more surely to escape them.

So it was that while Rajah Muda Saffir moved leisurelyup the river toward his distant stronghold waiting forthe other boats of his fleet to overtake him, Barunda,the headman, guided the white enemy swiftly after him.Barunda had discovered that it was the girl alone thiswhite man wanted. Evidently he either knew nothing ofthe treasure chest lying in the bottom of Muda Saffir'sboat, or, knowing, was indifferent. In either eventBarunda thought that he saw a chance to possess himselfof the rich contents of the heavy box, and so served hisnew master with much greater enthusiasm than he had the old.

Beneath the paddles of the natives and the fiveremaining members of his pack Bulan sped up the darkriver after the single prahu with its pricelessfreight. Already six of the creatures of ProfessorMaxon's experiments had given up their lives in theservice of his daughter, and the remaining six werepushing forward through the inky blackness of thejungle night into the untracked heart of savage Borneoto rescue her from her abductors though they sacrificedtheir own lives in the endeavor.

Far ahead of them in the bottom of the great prahucrouched the girl they sought. Her thoughts were ofthe man she felt intuitively to possess the strength,endurance and ability to overcome every obstacle andreach her at last. Would he come in time? Ah, thatwas the question. The mystery of the stranger appealedto her. A thousand times she had attempted to solvethe question of his first appearance on the island atthe very moment that his mighty muscles were needed torescue her from the horrible creature of her father's creation.Then there was his unaccountable disappearance for weeks;there was von Horn's strange reticenceand seeming ignorance as to the circumstanceswhich brought the young man to the island,or his equally unaccountable disappearanceafter having rescued her from Number One.And now, when she suddenly found herselfin need of protection, here was the sameyoung man turning up in a most miraculous fashion,and at the head of the terrible creatures of the inner campong.

The riddle was too deep for her--she could not solve it;and then her thoughts were interrupted by the thin,brown hand of Rajah Muda Saffir as it encircled herwaist and drew her toward him. Upon the evil lips werehot words of passion. The girl wrenched herself fromthe man's embrace, and, with a little scream of terror,sprang to her feet, and as Muda Saffir arose to graspher again she struck him full in the face with one small,clenched fist.

Directly behind the Malay lay the heavy chestof Professor Maxon. As the man stepped backwardto recover his equilibrium both feet struck the obstacle.For an instant he tottered with wildly waving armsin an endeavor to regain his lost balance, then,with a curse upon his lips, he lunged across the boxand over the side of the prahu into the dark watersof the river.