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Patent Model of a Machine for Coating Electrotype Molds with Plumbago

Patent Model of a Machine for Coating Electrotype Molds with Plumbago

Description (Brief)
This patent model demonstrates an invention for a machine for coating electrotype; the invention was granted patent number 85411. The patent details a machine for brushing black lead (plumbago, graphite) or bronze powder onto either wax or gutta percha molds, in order to give them conducting surfaces. Stephen Tucker was an employee and, from I860, a partner with R. Hoe & Co. He was responsible for numerous patents for the company, and was the author of the company history, "A History of R. Hoe & Company, 1834- 1885.”
Currently not on view
Object Name
machine, electrotype coating
Object Type
Patent Model
date made
ca 1868
patent date
Tucker, Stephen D.
Physical Description
metal (overall material)
wood (overall material)
overall: 24.8 cm x 16.8 cm x 27.8 cm; 9 3/4 in x 6 5/8 in x 10 15/16 in
ID Number
patent number
accession number
catalog number
See more items in
Work and Industry: Graphic Arts
Industry & Manufacturing
Patent Models
Patent Models, Graphic Arts
Data Source
National Museum of American History
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