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A method whereby drawings of objects under the microscope, of rare specimens of plants, insects, and other things, may be accurately, easily, and inexpensively multiplied has long been desired. Numerous attempts have been made to meet these requirements, but none with which I am acquainted seems to yield such satisfactory results as that lately perfected by Mr. A. Pumphrey, of Birmingham, which he calls the Autographic Printing process. This is a method, invented and patented by him, by which anything written or drawn with ink on paper can be multiplied to any extent, In absolute facsimile, and in any one colour. It differs from the Papyrograph and other devices of that kind in the fact that fine lines can be reproduced in all their perfection; another and very great advantage is that the original is in no way injured, as is the case in most other methods. A desire having been expressed by members of the Birmingham Natural History and Microscopical Society to see the process in actual work, the inventor attended at the Society's meeting, held on Tuesday, April 2nd, and gave an account of the process, and then proceeded to employ it in reproducing a number of various kinds of drawings. These sketches, prepared beforehand by members, having been given to Mr. Pumphrey, a prepared slab of slate, counted with a special preparation of gelatine, (which can be kept ready for use for an indefinite length of time,) was moistened with a solution of bichromate of potash, the drawing to be copied was placed in contact with the surface for a few seconds, and the ink on the paper, where it touched the gelatine, affected it and made it horny. Without any further operation, an ordinary inking roller was passed over the gelatine, the ink adhering to the slab only where the writing had touched. Clean paper was then laid upon it, and a little pressure produced a perfect copy. After one print was taken, the slab was moistened with clean water, and the operation repeated, With this number of the Magazine will be found a number of plates thus obtained, which reproduce the original drawings with excellent effect.

Is was at first supposed that any ink and paper would suffice, but the materials of which these are made are so various that it is advisable to use only those kinds which have been found to be most satisfactory. The chief requisite of the ink is that it should contain am excess of iron. Ink and paper of the best kind can he obtained from the patentee, Emily Street, Birmingham, and from Mr. T. Bolton, at his Microscopist's and Naturalists' Studio, 17, Ann Street, Birmingham, both of whom supply, at a small charge, a book giving full details how to obtain the best results, and a compact and handy apparatus, by means of which the printing can be done, as has been practically proved, by anyone. The price of this, with every requisite for producing prints similar to these