inventions

Josiah Warren’s 1830 “Reduction in the Cost of Printing Apparatus” described one of his attempts to make the power of the press widely available. An 1846 patent (#4479) issued for “Improvement in Compositions for Stereotype-Plates” marked on advance in this project. Matrices of a composite material, largely made up of clay, took the place of the lead matrices proposed in 1830 (themselves an improvement of copper matrices, in terms of the ease with which they could be used. (There is a reissue on file for either 1853 or 1883.) It took me quite awhile to actually find this patent, although […]