There appears to be another species of magic mirror, of which few examples are known, having the property of showing in the face a pattern entirely different from that on the back. Three such are mentioned by Ayrton, though it does not seem that he himself had inspected any of them personally. One of these, which he states to exist at Kamakura, the old capital of the former Shoguns, is a religious mirror about four inches and one-fifth high, by three and a half wide, held in great reverence. In the polished surface, when looked at very obliquely, is seen the image of a Buddhist priest. The pattern on the back is a rosary in high relief with a branch of plum-blossom, and a crescent moon rising out of the sea as a background. It is said that this optical effect is produced by chemically etching the surface with an acid paste, and then repolishing. Professor Ayrton, who had two mirrors made thus by a Japanese mirror-maker, found that if the face of a mirror that had so been etched was repolished until every trace of the marks disappeared in direct or oblique vision, they then entirely disappeared also from the image cast by the mirror in reflecting a beam of light upon a screen. He greatly doubted whether chemical means could produce a mirror possessed of true magic properties. The cause of the phenomena of the Kamakura mirror and its congeners--should the facts be established as narrated--therefore remains still to be explained. Though in the case of the ordinary Japanese mirrors science completely explains what would otherwise seem to be a most mysterious and unaccountable phenomenon, the explanation itself involves a very remarkable fact, namely, that there can exist such very delicate and minute differences of curvature in the polished face as to be practically invisible for ordinary purposes, and difficult even of scientific detection, and yet that those minute differences in curvature should be in such exact correspondence to the patterns on the back as to reproduce those patterns in the reflected beams of light. The facts seem so utterly unlikely _à priori_ to be true, that one can only give full credence to them after the most searching scientific demonstration. But is not this, after all, only another example of the truism that when science explains away one mystery she does so by establishing some truth that is itself still more mysterious? [Illustration: _The Mirror of Kamakura._] [Illustration: JAPANESE WOMAN DANCING, WITH MIRROR. From a bronze plate (_modern_).] [Illustration] APPENDIX I. BIBLIOGRAPHY OF THE MAGIC MIRROR. PART I. REAL MAGIC MIRRORS. BREWSTER, SIR DAVID. Account of a curious Chinese Mirror, etc. _Philosophical Magazine_, vol. i., p. 438, 1832. See also _Poggendorff’s Annalen_, xxvii., pp. 485-489, 1833. [Translation of the preceding], and _Journal Franklin Institution_, vol. xv., p. 128, 1832.