From the depths of his gorgeous robe, Lien Weng took a small gun-metal case. A spring released the top. Within was a tiny glass phial, in the form of a syringe, containing about an ounce of a colorless fluid. So delicate was the whole contrivance that it could be concealed in the palm of one hand. After Lien Weng had placed it on the table in front of him, he went on to explain its nature and its use. The fluid was the most subtle and the most deadly poison science had yet evolved. Distilled in minute quantities by a recent chemical process from a rare herb indigenous to the Manchurian wilds, the secret was known to the Society alone, and its use was strictly regulated by its laws. In operation, as Lien Weng explained, it was very simple. By discharging the contents of the phial on the back of a person’s coat, of no matter what thickness, at a point midway between the shoulder blades, it would percolate in the course of less than three hours to the spinal marrow. And, without warning of any kind, it would bring about a sudden and complete collapse of the nervous system. Death would at once ensue and not leave a trace of its cause. So subtle was the work of this poison that it defied all medical diagnosis. Its operation was impossible to detect. Autopsies were vain. The police of London, New York, Bombay, Shanghai could only surmise that such a thing existed without being able to prove the fact. Indeed they were faced by a problem with which they could not deal; a problem so elusive that it merged cause in effect. Succinctly and gently, with the air of a British judge addressing a British jury, Lien Weng expounded all this to John Endor. He was required to use the lethal weapon formally entrusted to him now by the decree of the Council of Seven within the time appointed and in the manner specified. “And if, sir, one does not choose to carry out this horrible task?” said Endor, quietly. “Sir,” was the President’s soft reply, “since you have taken the oath of our Society is it really necessary for me to answer your question?” Endor looked earnestly at the faces of the six men around him, as if he would peer into their minds. Again he was undecided as to what his immediate course of action should be. His first thought was to defy these fanatics by flinging the phial into the fire. But as his fingers closed upon the slender tube of glass, the mysterious _prana_ deep down in every healthy nature intervened to save him. An overt act of that kind, as the faces around told him very surely, would mean certain death. At the call of an obscure law of being Endor slowly returned the cylinder to its gun-metal sheath. And then fully sensible of six pairs of eyes fixed upon him, he took from his breast pocket a cigarette case and calmly placed within it this most deadly of weapons. “Sir, you have until to-morrow Monday week at midnight,” were Lien Weng’s final words.