Mechanical Navigator by F. E. Brandis, Sons and Company
date: label: date made
content: 1890-1916
name: label: maker
content: F. E. Brandis, Sons and Company
notes: label: Description
content: The mechanical navigator is an analog computing device designed to solve problems in spherical trigonometry arising in navigation. In this form, it was designed for instruction in navigation (another version was designed for use at sea). It allowed a student to compute a ship’s location from two sights in one operation.
label: Description
content: The instrument is a mechanical representation of the celestial sphere. A rotating ring mounted vertically on the right side represents the celestial equator. It is calibrated from 0 to 180 by quarter-degrees twice, representing celestial longitude. It also is graduated from 0 to 24 counterclockwise by one minute, and from 0 to XXIV clockwise by one minute. The iron housing inside the vertical circle is calibrated from 0 to 22 by one and labeled by constellation name. A vernier along the edge of this ring marks the meridian of the navigator.
label: Description
content: The instrument has two concentric rings which rotate in perpendicular planes. The outermost represents an hour circle. It is calibrated from 0 to 90 by quarter-degree, four times, and also bears hour lines. The inner ring represents the horizon circle. In addition to degree scales like those of the hour circle, it has is letters for eight cardinal points with sixteen subdivisions between each letter.
label: Description
content: A quadrant affixed perpendicular to the horizon ring, has scales calibrated scale along both sides that run from 0 to 90 degrees, divided to quarter degrees and marked every ten degrees. These represent degrees of latitude. All of these parts rotate on pivots. There are screws for setting the circles.
label: Description
content: The iron base, in the shape of a “T,” has handles at each end. A prior owner made a fitted wooden base for the navigator. The base has two boards with a space between them. Two removable wooden rods labeled in pencil “Left” and “Right” rest between the boards. A mark engraved on the vertical ring reads: F. E. BRANDIS, SONS & CO. (/) BROOKLYN, N.Y. (/) 2877.
label: Description
content: Frederick Ernest Brandis (1845-1916) was a German immigrant who began making and importing instruments in 1871. From the name of the firm, the instrument was made between 1890 and 1916. An eighteen-page typescript of the company’s instructions for using the mechanical navigator is stored in the accession file. According to an account of the instrument published in </>Engineering News</I> in 1914, the mechanical navigator sold for $2400.
label: Description
content: Another example of the mechanical navigator has long been on loan to the physical sciences collection.
label: Description
content: References:
label: Description
content: Brandis & Sons Mfg. Co., <I>Instruments of Precision . . . Catalogue No. 20</I> (Brooklyn, New York, n.d.), pp. 294-297.
label: Description
content: "Instrument for Solving Problems of Navigation," <i>Scientific American</i> (July 16, 1910): 44,56,57.
label: Description
content: “An Instrument for Solving Spherical Triangles Mechanically,” <I>Engineering News</I>, vol. 71 #4, January 22, 1914, pp. 180-181.
label: Description
content: Mimeographed instructions describing the instrument and its use in detail, are in the accession file.
label: Location
content: Currently not on view
place: label: place made
content: United States: New York, New York City
label: place made
content: United States: New York, Brooklyn
topic: label: Subject
content: Mathematics
label: Subject
content: Navigation
label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Trigonometry
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content: Science & Mathematics
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content: Spherical Trigonometry
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.314665
label: accession number
content: 208323
label: catalog number
content: 314665
objectType: label: Object Name
content: mechanical navigator
physicalDescription: label: Physical Description
content: metal (overall material)
label: Physical Description
content: wood (base material)
label: Measurements
content: overall: 26 cm x 44.4 cm x 27.7 cm; 10 1/4 in x 17 15/32 in x 10 29/32 in