Published in 1874, this collection of reports by the chemist and scientific journalist Sir William Crookes (1832-1919) describes his controversial research into psychic forces. In 1870, Crookes decided that science had a duty to study preternatural phenomena associated with spiritualism, and he spent the next four years carrying out experiments which tested famous mediums including D. D. Home, Kate Fox and Florence Cook. This fascinating work describes Crookes' witnessing of the movement of bodies at a distance, rappings, changes in the weights of bodies, levitation of individuals and automatic writing. Although he was strongly criticised by his contemporaries, Crookes would not be deterred from his psychical research, demonstrating that he thought all natural phenomena worthy of scientific investigation. A great experimentalist, Crookes refused to be bound by tradition and convention, and his story reveals one of the important episodes in the history of the spiritualist movement.