"'If our country is at war at the time you read this, your duty is plain. I have no fears regarding your course of action. But if not, I do not care to influence unduly your decision about venturing into this unknown other world. The danger into which I personally may have fallen must count for little with you, in a decision to hazard your own lives. I may point out, however, that such a journey successfully accomplished cannot fail but be the greatest contribution to science that has ever been made. Nor can I doubt but that your coming may prove of tremendous benefit to the humanity of this other equally important, though, in our eyes, infinitesimal world. "'I therefore suggest, gentlemen, that you start your journey into the ring at 8 P. M. on the evening of November 4, 1923. You will do your best to find your way direct to the city of Arite, where, if I am alive, I will be awaiting you.'" CHAPTER X TESTING THE DRUGS The Doctor laid his papers on the table and looked up into the white faces of the three men facing him. "That's all, gentlemen," he said. For a moment no one spoke, and on the face of each was plainly written the evidence of an emotion too deep for words. The Doctor sorted out the papers in silence, glanced over them for a moment, and then reached for a large metal ash tray that stood near him on the table. Taking a match from his pocket he calmly lighted a corner of the papers and dropped them burning into the metal bowl. His friends watched him in awed silence; only the Very Young Man found words to protest. "Say now, wait," he began, "why----" The Doctor looked at him. "The letter requests me to do that," he said. "But I say, the formulas----" persisted the Very Young Man, looking wildly at the burning papers. The Doctor held up one of the white tin boxes lying on the arm of his chair. "In these tins," he said, "I have vials containing the specified quantity of each drug. It is ample for our purpose. I have done my best to memorize the formulas. But in any event, I was directed to burn them at the time of reading you the letter. I have done so." The Big Business Man came out of a brown study. "Just three weeks from to-night," he murmured, "three weeks from to-night. It's too big to realize." The Doctor put the two boxes on the table, turned his chair back toward the others, and lighted a cigar. "Gentlemen, let us go over this matter thoroughly," he began. "We have a momentous decision to make. Either we destroy those boxes and their contents, or three weeks from to-night some or all of us start our journey into the ring. I have had a month to think this matter over; I have made my decision.