Spectroscope

Prisms spread light into colored lines, and the lines showed which elements were in a glowing flame or star.

Date: 1873-1881
Maker: William Grunow
Place: United States: New York, New York City
Dimensions: base: 17 1/2 in x 6 in; 44.45 cm x 15.24 cm; overall: 7 5/8 in x 8 in x 18 1/4 in; 19.3675 cm x 20.32 cm x 46.355 cm
Museum: National Museum of American History
Credit line: United States Military Academy

This is a six-prism instrument on a rectangular base. The “Wm. Grunow / New York” inscription refers to William Grunow (1830-1917), a German craftsman who, with his brother Julius, came to the United States in 1849 and went to work making microscopes. In 1873, now settled in New York, Grunow announced his willingness “to execute all orders for philosophical instruments.” In 1881 he moved to West Point, and spent the next 36 years as custodian of the astronomical observatory of the U.S. Military Academy.

Ref: D.J. Warner, “Julius & William Grunow,” Rittenhouse 3 (1989): 41-48.

The museum's own record (Smithsonian, National Museum of American History)

Spectroscope

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