Koch & Co. Protractor
date: label: date made
content: before 1900
name: label: maker
content: Koch & Co.
notes: label: Description
content: This device for measuring angles bears some resemblance to a combination of a sector and dividers. Two steel arms are screwed together so that one arm may be squeezed and the tops of the arms may pinch an object. The stationary arm is split so that the tension on the arms may be adjusted at the screw. The stationary arm is fastened to a brass piece that is divided by single degrees and marked by tens from 0° to 100°. When the other arm is squeezed, it points to a measurement on the brass piece.
label: Description
content: An owner's signature on the back of the brass piece appears to read, in script, "bgulp." The letters may be Cyrillic or German. A maker's mark is stamped on the back of the stationary arm: KOCH & Co. The firm to which this maker's mark refers is not known. The Department of Entomology in the National Museum of Natural History acquired this object in the late 19th century for use in research. The object is rusted and tarnished.
label: Location
content: Currently not on view
topic: label: Subject
content: Mathematics
label: Subject
content: Protractor
label: Subject
content: Entomology
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: Protractors
creditLine: label: Credit Line
content: Transfer from National Museum of Natural History
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1990.0099.05
label: accession number
content: 1990.0099
label: catalog number
content: 1990.0099.05
objectType: label: Object Name
content: protractor
physicalDescription: label: Physical Description
content: brass (overall material)
label: Physical Description
content: steel (overall material)
label: Measurements
content: overall: .4 cm x 15 cm x 9 cm; 5/32 in x 5 29/32 in x 3 17/32 in