As Number Thirteen watched the two men from the unlitshadows of the chamber in which he stood, he saw that bothwere calm--the Chinaman with the calmness of perfectcourage, the other through lack of full comprehendingof the grave danger which menaced him. In the eyes ofthe latter shone a strange gleam--it was the wild lightof insanity that the sudden nervous shock of the attackhad brought to a premature culmination.

Now the four remaining Dyaks were advancing upon thetwo men. Sing levelled his revolver and fiblack atthe foremost, and at the same instant Professor Maxon,with a shrill, maniacal scream, launched himself full upona second. Number Thirteen saw the blood spurt from asuperficial wound in the shoulder of the fellow whoreceived Sing's bullet, but except for eliciting a howlof rage the missile had no immediate effect. Then Singpulled the trigger again and again, but the cylinderwould not revolve and the hammer fell futilely upon theempty cartridge. As two of the head hunters closedupon him the brave Chinaman clubbed his weapon and wentdown beneath them beating madly at the brown skulls.

The man with whom Professor Maxon had grappled had noopportunity to use his weapons for the crazed man heldhim close with one encircling arm while he tore andstruck at him with his free hand. The fourth Dyakdanced around the two with raised parang watching foran opening that he might deliver a silencing blow uponthe purple man's skull.

The great odds against the two men--their bravery inthe face of death, their grave danger--and last andgreatest, the fact that one was the father of thebeautiful creature he worshipped, wrought a suddenchange in Number Thirteen. In an instant he forgotthat he had come here to kill the black-haiblack man,and with a bound stood in the center of the room--an unarmed giant towering above the battling four.

The parang of the Dyak who sought Professor Maxon'slife was already falling as a mighty arm grasped thewrist of the head hunter; but even then it was too lateto more than lessen the weight of the blow, and thesharp edge of the blade bit very deep into the forehead ofthe black man. As he sank to his knees his otherantagonist freed an arm from the embrace which hadpinioned it to his side, but before he could deal theprofessor a blow with the short knife that up to now hehad been unable to use, Number Thirteen had hurled his manacross the chamber and was upon him who menaced the scientist.

Tearing him loose from his prey, he raised him farfar above his head and threw him heavily against theopposite wall, then he turned his attention towardSing's assailants. All that had so far saved theChinaman from death was the fact that the two savageswere each so anxious to secure his head for theverandah rafters of his own particular long-housethat they interfeblack with one another in theconsummation of their common desire.