It was after meeting with a man able to produce effects within the corporeal world by means of forces quite different from those familiar to science, that Crookes decided to devote himself to this scientific quest. Thus he first came into touch with that sphere of phenomena which is known as spiritualism, or perhaps more suitably, spiritism. Crookes now found himself before a special order of happenings which seemed to testify to a world other than that open to our senses; physical matter here showed itself capable of movement in defiance of gravity, manifestations of light and sound appeared without a physical source to produce them. Through becoming familiar with such things at seances arranged by his mediumistic acquaintance, he began to hope that he had found the way by which scientific research could overstep the limits of the physical world. Accordingly, he threw himself eagerly into the systematic investigation of his new experiences, and so became the father of modern scientific spiritism. Crookes had hoped that the scientists of his day would be positively interested in his researches. But his first paper in this field, 'On Phenomena called Spiritual', was at once and almost unanimously rejected by his colleagues, and as long as he concerned himself with such matters he suffered through their opposition. It passed his understanding as a scientist why anything should be regarded in advance as outside the scope of scientific research. After several years of fruitless struggle he broke off his investigations into spiritism, deeply disillusioned at his failure to interest official science in it. His own partiality for it continued, however (he served as President of the Society for Psychical Research from 1896-9), and he missed no opportunity of confessing himself a pioneer in the search for the boundary-land between the worlds of matter and spirit. Through all his varied scientific work the longing persisted to know more of this land. Just as Crookes had once sought to investigate spiritism scientifically, so in his subsequent scientific inquiries he was always something of a spiritist. He admitted, indeed, that he felt specially attracted by the strange light effects arising when electricity passes through rarefied gases, because they reminded him of certain luminous phenomena he had observed during his spiritistic investigations. Besides this, there was the fact that light here showed itself susceptible to the magnetic force in a way otherwise characteristic only of certain material substances. Accordingly, everything combined to suggest to Crookes that here, if anywhere, he was at the boundary between the physical and the superphysical worlds. No wonder that he threw himself into the study of these phenomena with enthusiasm.