After Helen had spent an entrancing hour in talk with Mr. Wygram, she gleaned from her hostess by dint of judicious inquiry that he was now recognized the world over as an authority upon the Unseen. She learned further that this remarkable man had found a solution to more than one mystery that seemed impenetrable and that the police often had recourse to his services. This view of Wygram’s unique powers was supported by the attention paid him by Saul Hartz. It was never a habit of the Colossus to flatter the vanity of his fellow men by sitting in public at the feet of Gamaliel. But it was clear to Helen that the orientalist had some potent attraction for him. More than once in the course of that day she saw the two men together in quiet corners. And to judge by the look of concentration on Mr. Hartz’s face the subject of their talk was to him of vital concern. At dinner, no doubt as a concession to the keen curiosity Helen had shown in regard to Mr. Wygram, she was taken in by him. Further acquaintance did but add to the interest he excited in her. Little passed between them that average people could have laid hold of as definitely enlarging the boundaries of human knowledge, but Helen felt all the same that her approach to certain subjects whose importance and value she could but vaguely surmise would from now on be more practical, more scientific, more expert. “How far do you think it possible,” she ventured to ask, “for one mind, or for a group of minds, to act subconsciously upon the mind of another person, without coming into direct contact with it, in order to control its actions?” “An interesting speculation!” Wygram spoke with the simple candor of one very much a master of his subject. “I think myself the science--and as one happens to know, a dark and terrible science it is, which the East has already brought to an uncanny perfection--of imposing one’s will upon the will of another is being developed to a point which threatens some very ugly developments.” “That is just what one feels oneself,” said Helen. “Only the other day,” said Wygram, “I was called in by the New York police to help in a terrible case which has made a great impression over there. It was that of a man, otherwise presumably sane, who committed a perfectly senseless and illogical crime because a deadly enemy, an expert practitioner of the new science, had been able to tamper with the mind of that man subconsciously while he slept.” “How dreadful!” Wygram agreed that the speculations opened up by a fact so sinister were not pleasant. “The whole world is on the down grade,” he said. “Man has played things up too high. For many years he has been dealing with unclean things--subtle poisons, high explosives, black magic. But to my mind this new science which has come out of the East is the worst of all, because it is by far the most elusive.” “Can it be used, do you suppose, on a large scale?”