Davis Sextant

William A. Davis was an Englishman who settled in San Leandro, California, and offered a range of inexpensive plastic nautical instruments for boating enthusiasts. He introduced the Mark III sextant in 1963, and the instrument is still in production. Like the sextant that Cruver made for the U.S. Maritime Commission during the war, the Mark III is made of polystyrene. It has a simple eye tube, and a scale that is graduated every degree from -35° to +100° and read by vernier to 2 minutes of arc. The original Mark III cost $9.95. This example was probably made in the late 1960s. The sextant's arm is inscribed "DAVIS INSTRUMENTS CORP. / 857 THORNTON STREET / SAN LEANDRO / CALIF. 94577 / U.S.A."
Ref: William A. Davis, How to Find Your Position with a Sextant (San Leandro, 1966 and 1968).
Currently not on view
Object Name
Davis Instruments Corporation
Physical Description
plastic (overall material)
radius: 7 in; 17.78 cm
ID Number
catalog number
accession number
Measuring & Mapping
See more items in
Medicine and Science: Physical Sciences
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Roger Sherman

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.