There was a little smile of disbelief on Dean's face. Yamada went on quietly. "You do not believe because you do not understand. There are not many who can comprehend, or who wish to comprehend, this greater science which is not bound by earthly laws. But here is a problem for you, Mr. Dean." A little spark of irony flickered in the black eyes. "Can you tell me how I know you have suffered from nightmares recently?" Dean jerked around and stood staring. Then he smiled. "As it happens, I know the answer, Doctor Yamada. You physicians have a way of hanging together--and I must have let something slip to Doctor Hedwig yesterday." His tone was offensive, but Yamada merely shrugged slightly. "Do you know your Homer?" he asked, apparently irrelevantly, and at Dean's surprized nod went on, "And Proteus? You remember the Old Man of the Sea who possessed the power of changing his shape? I do not wish to strain your credulity, Mr. Dean, but for a long time students of the dark lore have known that behind this legend there exists a very terrible truth. All the tales of spirit-possession, of reincarnation, even the comparatively innocuous experiments in thought-transference, point to the truth. Why do you suppose folklore abounds with tales of men who have been able to change themselves into beasts--werewolves, hyenas, tigers, the seal-men of the Eskimos? Because these tales are founded on truth! "I do not mean," he went on, "that the actual physical metamorphosis of the body is possible, so far as we know. But it has long been known that the intelligence--the mind--of an adept can be transferred to the brain and body of a satisfactory subject. Animals' brains are weak, lacking the power of resistance. But men are different, unless there are certain circumstances----" As he hesitated, Dean proffered the Japanese a cup of coffee--coffee was generally brewing in the percolator these days--and Yamada accepted it with a formal little bow of acknowledgment. Dean drank his coffee in three hasty gulps, and poured more. Yamada, after a polite sip, put the cup aside and leaned forward earnestly. * * * * * "I must ask you to make your mind receptive, Mr. Dean. Don't allow your conventional ideas of life to influence you in this matter. It is vitally to your interest that you listen carefully to me, and understand. Then--perhaps----" He hesitated, and again threw that oddly furtive glance at the window.