Within twenty-four hours more we knew, and all at the university knew, that Dr. Grant had disappeared. From the meeting he went to his laboratory, burned some papers there and pocketed others. Then he went to his rooms, hastily packed a few bags and departed. He left no note, no message. His action brought to a climax the whole sensation of the controversy he had precipitated and Grant's going was taken by many of his critics as a confession of the falsity of his position. He had had no close relatives to start a search for him, and though to Ferson and me his strange departure seemed astounding, we could explain it no better than others. The sensation subsided, and Ferson was appointed to head the department in place of the vanished scientist. Our own work occupied us once more. And certainly neither Ferson nor I, any more than another, guessed what lay behind Grant's strange action. * * * * * It was six months after Grant's departure that the great change began. The first intimation was brought to the public notice by a New York newspaper. In a sensational article entitled "Is a New Crime Wave Upon Us?" it pointed out that in the last few days an unprecedented number of crimes of violence had taken place. These were the more appalling in that many seemed quite without motive. In New York alone, in those few days, there had been more than a dozen murders, mostly clubbings and stabbings, which had apparently been provoked by the slightest of causes. In Chicago a respected clerk of middle age had for some annoyance turned suddenly and fractured the skulls of three of his associates with a heavy bar. From San Francisco and Los Angeles had come news of half a dozen holocausts in which one member of a family had slaughtered or attempted to slaughter all the others. From every part of the land there were coming reports of the most horrifying crimes of violence, the great majority of which seemed inspired by the pettiest of causes. And this same wave of homicidal mania seemed at work over all the world! It was as though hundreds in earth's population had suddenly had their reason dwarfed and their passions magnified. No less than three solid householders in London had run amuck in bursts of sadistic[1] fury that had cost a half-score lives. The Paris police had taken from the Seine more human bodies, many terribly mutilated, than had ever been found in it in a like time before. Germany was aghast over two mass-murders of unexampled fiendishness that had occurred in a Rhenish and a Silesian village. There was news of an even more terrible slaying in Calcutta, and word of murders almost as terrible from almost every country on the globe. [Footnote 1: Sadism, of which this word is the adjective, is a mental perversion towards cruelty.]