"And," Dr. Erwin went on frigidly, "if we had found absolutely nothing we would, at least, have kept silent about an unsuccessful research, it is useless to say. Think, then, my dear Master, the exterior objects must have imprinted themselves on the retina, did they not? reduced in size, according to the size of the place wherein they were reflected; they appeared there, they certainly appeared there! There is--I beg your pardon for referring to it, but it is to these others (and Dr. Erwin designated M. Ginory, his registrar, and Bernardet)--there is in the retina a substance of a red color, the _pourpre retinien_, very sensitive to the light. Upon the deep red of this membrane objects are seen white. And one can fix the image. M. Edmond Perrier, professor in the Museum of Natural History, reports (you know it better than I, my dear Master), in a work on animal anatomy and physiology which our students are all familiar with, that he made an experiment. After removing a rabbit's eye, a living rabbit's eye--yes, science is cruel--he placed it in a dark room, so that he could obtain upon the retina the image of some object, a window for instance, and plunged it immediately into a solution of alum and prevented the decomposition of the _pourpre retinien_, and the window could plainly be seen, fixed on the eye. In that black chamber which we have under our eyebrows, in the orbit, is a storehouse, a storehouse of images which are retained, like the image which the old Dane's eye held of the wolf's nose and teeth. And who knows? Perhaps it is possible to ask of a dead man's eye the secret of what it saw when living." This was, put in more scientific terms by the young Danish doctor, the substance of what Bernardet believed possible. The young men had listened with the attractive sympathy, which is displayed when anything novel is explained. Rigid, upon the marble slab, the victim seemed to wait for the result of the discussion, deaf to all the confused sounds about him; his eye fixed upon the infinite, upon the unknowable which he now knew. It was, however, this insensible body which had caused the discussion of what was an enigma to savants. What was the secret of his end? The last word of his agony? Who made that wound which had ended his life? And like a statue lying on its stone couch, the murdered man seemed to wait. What they knew not, he knew. What they wished to know, he still knew, perhaps! This doubt alone, rooted deep in M. Ginory's mind, was enough to urge him to have the experiment tried, and, excusing himself for his infatuation, he begged M. Morin to grant permission to try the experiment, which some of the doctors had thought would be successful. "We shall be relieved even if we do not succeed, and we can but add our defeat to the others."