Proportional Dividers by Kern
date: label: date made
content: early 20th century
name: label: maker
content: Kern & Co.
notes: label: Description
content: Engineers and surveyors have long used proportional dividers to mark off equal segments on a line or the circumference of a circle. This instrument also permits a draftsman to proportionally enlarge or reduce a portion of a drawing while reproducing the drawing. Although drawing instruments such as dividers were the first objects produced when Jakob Kern established his workshop in Switzerland in 1819, this example dates from the early 20th century, by which time Kern & Co. of Aarau was internationally prominent.
label: Description
content: The two main slides are nickel silver, and the points are steel. On one end, the points are 1/2" long; on the other, they are 3" in length. The longer points are quite rusted. The slides are connected with a screw. A smaller steel slide is attached by two screws to the slide for planes and solids. There are two scales, each divided proportionally, on each slide. On one slide, the first scale is marked by ones from 2 to 10 and engraved SOLIDS. The second scale is marked by ones from 2 to 10 and engraved PLANES. On the second slide, one scale is marked by ones from 6 to 20, with a division marked GS at the lower end of the scale and CIRCLES engraved at the upper end of the scale. The second scale is marked irregularly (11/12; 9/10; 7/8; 5/6; 4/5; 3/4; 2/3; 3/5; 2; 2/5; 3; 4; 5; 6; 7; 8; 9; 10) and engraved LINES.
label: Description
content: The maker’s mark—KERN & CO. [/] AARAU SWISS—is obscured by a museum mark. The number 640 is engraved near the maker’s mark and above the company logo, a K within a pair of dividers. The dividers are housed in a case of morocco leather over wood, lined with green velvet and locked by a button on the side. The top of the case is imprinted with a rectangle that has a fleur-de-lis at each corner. Inside the case, the Museum number (321-781) is written on a ribbon pasted over the maker’s mark, which reads: SWISS; KERN & CO. A word precedes “Swiss,” but it is illegible. The Interstate Commerce Commission transferred these dividers to the Smithsonian in 1963.
label: Location
content: Currently not on view
place: label: place made
content: Switzerland: Aargau, Aarau
topic: label: Subject
content: Mathematics
label: Subject
content: Dividers
setName: label: See more items in
content: Medicine and Science: Mathematics
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content: Science & Mathematics
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content: Dividers and Compasses
creditLine: label: Credit Line
content: Transfer from Interstate Commerce Commission
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.321781
label: accession number
content: 246883
label: catalog number
content: 321781
objectType: label: Object Name
content: proportional dividers
label: Object Name
content: dividers
physicalDescription: label: Physical Description
content: german silver (overall material)
label: Physical Description
content: leather (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: velvet (overall material)
label: Measurements
content: overall: 1.9 cm x 22.3 cm x 2.8 cm; 3/4 in x 8 25/32 in x 1 3/32 in