Cylinder-type Electrostatic Machine
date: label: date made
content: ca 1850
notes: label: Description (Brief)
content: People from ancient times knew that rubbing certain materials and then touching something caused a spark. Studying what is called electrostatics laid the groundwork for understanding electricity and magnetism. Natural philosophers, scientists, and instrument makers created many ingenious devices to generate electrostatic charges starting in the 1600s. These machines varied in size and technique but all involved rotary motion to generate a charge, and a means of transferring the charge to a storage device for use.
label: Description (Brief)
content: This rudimentary cylinder machine is incomplete, missing the rubbing pad and charge collector. The construction appears very crude without the detailing or polish seen on a commercially-made device. Two U.S. coins were used as retaining washers on the crank axle. During the 1750s electrical researchers refined the design of electrostatic machines by replacing earlier spherical globes with a glass cylinder, a design used for many years. This change increased the surface area of the glass in contact with the rubbing pad and improved the efficiency of the generator. There is almost no background information about this object that came into the collections from the Merrimac Valley Textile Museum in 1975.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
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content: Science & Mathematics
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content: Electrostatic Machines
creditLine: label: Credit Line
content: from the Merrimac Valley Textile Museum
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.333690
label: catalog number
content: 333690
label: accession number
content: 314579
objectType: label: Object Name
content: cylinder-type frictional electrostatic machine
label: Object Name
content: electrostatic generator
label: Other Terms
content: cylinder-type frictional electrostatic machine; Electrostatic Devices
physicalDescription: label: Physical Description
content: wood (overall material)
label: Physical Description
content: glass (overall material)
label: Physical Description
content: steel (overall material)
label: Measurements
content: overall: 25 1/4 in x 32 in x 14 1/2 in; 64.135 cm x 81.28 cm x 36.83 cm