|1.||Sometimes shortened to: electro a duplicate printing plate made by electrolytically depositing a layer of copper or nickel onto a mould of the original|
|2.||(tr) to make an electrotype of (printed matter, illustrations, etc)|
electroforming process for making duplicate plates for relief, or letterpress, printing. The process was first announced in 1838 by M.H. von Jacobi, a German working in St. Petersburg, Russia. Thomas Spencer and C.J. Jordan of England and Joseph A. Adams of the United States produced similar results the following year.
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