Ritchie-Holtz plate electrostatic machine, patent #74,139
date: label: Date made
content: 1868
name: label: maker
content: Ritchie, Edward S.
notes: label: Description (Brief)
content: A wooden base supporting a frictional generating machine consisting of a glass plate (8" diameter), revolving rubber disc and 4 rubber plates. Disc is revolved by a crank and band wheel. Two glass posts for adjustable sparking rods, one post broken and rod missing. Edward S. Ritchie, an instrument maker in Boston, received a U.S. patent for a Holtz electrical machine in 1868. This is the model he submitted with his patent application. Reference: U.S. Patent 74139, "Holtz electrical machine," issued 4 February 1868 to Edward S. Ritchie. "Ritchie's Holtz Machine," in E. S. Ritchie & Sons, <i>Ritchie's Illustrated Catalogue of Physical Instruments and School Apparatus</i> (Boston, 1877), page 79.
setName: label: See more items in
content: Work and Industry: Electricity
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.252648
label: catalog number
content: 252648
label: accession number
content: 49064
label: patent number
content: 74139
objectType: label: Object Name
content: Electrical Machine
label: Object Name
content: electrostatic generator
label: Object Name
content: electrostatic machine
physicalDescription: label: Measurements
content: overall: 8 1/2 in x 8 in x 10 in; 21.59 cm x 20.32 cm x 25.4 cm