1943 Schick incorporated U.S. Navy stadimeter
The stadimeter was developed in the 1890s by Bradley Allen Fiske (1854-1942), a Lieutenant in the United States Navy who had access to a laboratory in New York City that was fully backed by the Western Electric Manufacturing Co.1
The instrument was designed to determine the distance to an enemy warship, the mast head height of which was easily found in the naval literature. Although Fiske obtained several patents for rangefinders during the 1890s, it is not yet clear which of these patents pertained to the stadimeter.
Like a sextant, the stadimeter uses a system of mirrors to measure the angular distance of two ends of a distant object (e.g. height of a light house, length or height of a vessel). The difference with the sextant is that the user can set a reference scale (see figure 7) to a known dimension of that distant object. The stadimeter allows the user bring the two ends of the known object into coincidence, after which - provided the distance is set correctly - the distance to the object can be read from its drum micrometer (see figure 8).
The instrument was made by Schick Incorporated, Stamford, Connecticut, USA and was probably retailed by Graff, Washbourne & Dunn in New York as their label is fitted on the top side of the instrument (see figure 15).
Similar to the geodetic sextants in the collection the Schick stadimeter has three legs to rest the instrument on (see figure 12).
The stadimeter came into my collection in September 2005. It is complete with its original box. The lid has the original adjustment instructions (see figure 6) and even several spare parts can be found inside the box. Although the horizon mirror has a few speckles (see figure 14), the instrument still is in full working order.
Notes: Smithsonian National Museum of American History -> Browse by instrument -> Stadimeter
If you have any questions and/or remarks please let me know.
Celestial Navigation... Coastal Navigation... Distance measurement...
1943 U.S. Navy stadimeter Cotton Type Range Finder