Screw Propeller, Patent Model
date: label: Date made
content: 1875
label: patent date
content: 1875-04-13
name: label: patentee
content: Harrington, Jackson
label: inventor
content: Harrington, Jackson
notes: label: Description
content: This patent model represents Jackson Harrington's 1875 design for a "propeller-wheel," which improved upon a propeller he and a colleague invented in 1866.
label: Description
content: The Patent Office issued over 800 patents for paddle wheels, propellers, and other propulsion apparatus between 1790 and 1873. About 250 of these were propellers.
label: Description
content: Jackson Harrington and Francis Caffrey, then of New Haven, Connecticut, patented a six-bladed propeller design in 1866 that aimed to "enlarge the driving-surface" of the propeller "by means of parallel blades with an aperture between them." Nine years later, Harrington, now living in the town of Groton Bank outside New London, patented an improvement to his and Caffrey's earlier design. The new propeller still had six blades, but instead of grouping them in pairs around a single hub, he specified that three go on a forward hub and three on a rear hub. This arrangement aimed to make the propeller easier and cheaper to manufacture. Harrington further refined the shape of the blades and their positions relative to each other, toward the end of reducing friction between propeller and water.
label: Description
content: Harrington, born in 1827, and Caffrey, born in 1828, were both machinists.
label: Location
content: Currently not on view
place: label: Associated Place
content: United States: Connecticut, New Haven
topic: label: Subject
content: Patent Models
setName: label: See more items in
content: Work and Industry: Maritime
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content: America on the Move
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content: Transportation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: TR.308561
label: catalog number
content: 308561
label: accession number
content: 89797
label: patent number
content: 162,063
objectType: label: Object Name
content: screw propellor, patent model
label: Object Name
content: patent model, propeller, screw
label: Object Type
content: Patent Model
label: Other Terms
content: patent model, propeller, screw; patent model, screw propeller; propeller; Maritime
physicalDescription: label: Physical Description
content: brass (overall material)
label: Measurements
content: overall: 1 1/2 in x 3 in; 3.81 cm x 7.62 cm