THE MIMEOGRAPH.
Among the many inventions of Mr. Edison one of the most useful is the mimeograph. By means of it exact reproductions of typewriting may be made in a few moments and hundreds of fac-simile circulars produced in a short time. The process is a very simple one, and the sheets upon which the writing is done may be quickly prepared on any of the standard typewriters. These sheets are called "stencils." If the machine has a ribbon it must be unpinned or the ribbon mechanism arranged so the ribbon will not move, so that the type may strike directly against the stencil. A specially prepared waxen sheet is placed over a piece of fine silk and above that a sheet of tissue paper. These three sheets, with an oiled backing sheet, are placed in the typewriter as one would put in carbon sheets, the tissue sheet being uppermost. The typewriter is operated in the usual way. The bare type striking the tissue paper forces the impressions from the waxen sheet on to the piece of silk. The wax adheres to the silk and when the circular is completed the waxen sheet is found to be perforated wherever the type has struck it. The waxen sheet is taken from the machine, separated from the others, and fixed in a special frame with a porous sheet over it. By means of a roller, printer's ink is forced through the porous sheet and perforated waxen sheet on to a sheet of ordinary paper. This produces an exact
