Reproduction of Franklin electrostatic motor
date: label: date made
content: 1970
name: label: inventor
content: Franklin, Benjamin
label: maker
content: Cogar, Okey M.
notes: label: Description (Brief)
content: Reproduction of an electrostatic motor designed by Benjamin Franklin in 1748. This object was operated in the Electrostatics Hall at the National Museum of American History for many years by use of a power supply.
label: Description (Brief)
content: A static machine is connected to this motor such that the four Leyden jars are electrified alternately from each other, positive-negative-positive-negative. The center wheel is not connected to the static machine, so is not electrified. Each plastic arm holds a brass sewing thimble. A slight push sets the wheel spinning and a thimble is attracted to the nearest jar. A spark between that first jar and the thimble charges the thimble. Now charged like the first jar, the thimble is repelled from that jar and is attracted to the second jar which is oppositely charged. As the thimble passes the second jar, a spark reverses the charge on the thimble so that it is attracted to the third jar. The process repeats in turn with the third and fourth jars. Each thimble interacts with each jar as the wheel spins. That keeps the wheel moving. As the wheel turns, each thimble’s charge changes to match the jar it’s passing. Like charges repel, so the thimble is pushed to the next jar.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Okey M. Cogar
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2013.3081.01
label: nonaccession number
content: 2013.3081
label: catalog number
content: 2013.3081.01
objectType: label: Object Name
content: electrostatic motor
physicalDescription: label: Measurements
content: overall: 28 in x 29 in x 12 in; 71.12 cm x 73.66 cm x 30.48 cm