Proportional Dividers
date: label: date made
content: ca 1900
notes: label: Description
content: This instrument has brass slides with steel points. On one end, the points are 3/8" long; on the other, they are 1-3/4" in length. The longer points are corroded. Thumbscrews on both sides adjust the instrument along a gear and tooth mechanism (or "rack movement") on the back slide. The front slide is marked on both sides of the slot with what appears to be a single proportional scale for lines: 1/2, 1/3, 1/4, 1/5, 1/6, 7, 8, 9, 10. A wooden case fastened with brass hooks is lined with dark blue velvet. Red lines and numbers are on the bottom of the case. No legible maker's mark is present.
label: Location
content: Currently not on view
topic: label: Subject
content: Mathematics
label: Subject
content: Drawing Instruments
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
label: See more items in
content: Dividers and Compasses
creditLine: label: Credit Line
content: Gift of Ursula N. Forbes
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1986.0316.01
label: accession number
content: 1986.0316
label: catalog number
content: 1986.0316.01
objectType: label: Object Name
content: proportional dividers
label: Object Name
content: dividers
physicalDescription: label: Physical Description
content: brass (overall material)
label: Physical Description
content: velvet (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: steel (overall material)
label: Measurements
content: overall: 2.5 cm x 23 cm x 4.5 cm; 31/32 in x 9 1/16 in x 1 25/32 in