Rudolph Koenig (1832-1901), the leading acoustic instrument maker of his era, attended school in the Prussian city of Konigsberg and apprenticed with a French violin maker before opening his own shop in Paris in the late 1850s. Many Americans learned of his work through his extensive display at the Centennial Exhibition held in Philadelphia in 1876.

A tonometer is a set of tuning forks suitable for determining the pitch of other sounds. Johann Scheibler, a German silk manufacturer and acoustic researcher, suggested the instrument in 1834. His most advanced design consisted of 56 forks covering the range of a single octave. Koenig’s great tonometer, which he showed at the Centennial, had 670 tuning forks ranging in pitch from 16 to 4,096 hertz. In the early 1880s, this tonometer was purchased for use at the U.S. Military Academy.

The catalog number 315716 refers to a set of tuning forks and a rack which were transferred to the Smithsonian from West Point in 1958. This group of forks and rack are a part of the Koenig Tonometer exhibited at the Philadelphia Centennial Exposition of 1876. In 1882, parts of the Koenig apparatus were distributed to West Point, the University of Toronto, and Paris. Dr. Bernard Finn, a Smithsonian curator, discovered another group of forks during a visit to the University of Wisconsin in December 1962, but could find no record of how the forks came to the University. The forks from Wisconsin are cataloged under number 322452.

The image on this record depicts the forks from University of Wisconsin united with the rack and tuning forks from West Point.

Date Made: ca. 1876

Maker: Koenig, Rudolph

Location: Currently not on view

Place Made: France: Île-de-France, Paris

See more items in: Medicine and Science: Physical Sciences


Exhibition Location:

Data Source: National Museum of American History

Id Number: PH.315716Catalog Number: 315716Accession Number: 217544

Object Name: tonometer

Measurements: overall: 39 in x 50 1/2 in x 26 1/2 in; 99.06 cm x 128.27 cm x 67.31 cmoverall: 38 1/2 in x 50 1/4 in x 24 1/2 in; 97.79 cm x 127.635 cm x 62.23 cm


Record Id: nmah_1187821

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.