Locke Level
notes: label: Description
content: John Locke, a scientist in Cincinnati, Ohio, described a reflecting level at a meeting of the Association of American Geologists and Naturalists in 1842, and obtained a patent (#7,477) in 1850. Locke's instrument consisted of a small spirit level on a brass sighting tube, with a small diagonal reflector so arranged that the user can see the bubble and a distant sight at the same time. The inscription on the cardboard box of this example reads “LOCATOR’S LEVEL / MADE BY / KEUFFEL & ESSER CO. NEW YORK / FOR / ENGINEER DEPARTMENT, U. S. A."
label: Description
content: This level was used by Dr. Leonhard Stejneger (1851-1943), an ornithologist from Norway who worked at the Smithsonian Institution.
label: Description
content: Ref: Keuffel & Esser, Catalogue of Drawing Materials, Surveying Instruments, Measuring Tapes (New York, 1921), p. 363
label: Location
content: Currently not on view
setName: label: See more items in
content: Medicine and Science: Physical Sciences
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.320247
label: catalog number
content: 320247
label: accession number
content: 241910
objectType: label: Object Name
content: Locke level
physicalDescription: label: Measurements
content: level: 4 7/8 in x 1 in x 1 in; 12.3825 cm x 2.54 cm x 2.54 cm
label: Measurements
content: box: 5 in x 1 1/4 in x 1 1/4 in; 12.7 cm x 3.175 cm x 3.175 cm
label: Measurements
content: overall in box: 1 5/8 in x 5 3/8 in x 1 1/2 in; 4.1275 cm x 13.6525 cm x 3.81 cm