Mainka Conic (or Bifilar) Pendulum Seismograph
date: label: date made
content: ca 1911
name: label: maker
content: J. & A. Bosch
notes: label: Description
content: Francis Anthony Tondorf, S.J., director of the newly established seismological laboratory at Georgetown University, ordered several new seismographs in 1911. This one, which was advertised as “Dr. Mainka’s Small size Conic Pendulum,” was the first of its kind in the United States. It was designed by Carl Mainka, manager of the instrument department of the Imperial Station for earthquake investigations in Strasbourg, and manufactured by J. & A. Bosch, a firm that specialized in instruments for seismology and meteorology.
label: Description
content: This seismograph stands 1.6 meters high and has two 130-kilogram masses, one for each horizontal motion. Registration occurs on a smoked paper mounted on a rotating aluminum cylinder. It came to the Smithsonian in 1961.
label: Description
content: Ref: J. & A. Bosch, <i>Seismographen</i> (Strassburg, 1910), pp. 6-7.
label: Description
content: C. Mainka, “Das bifilare Kegelpendel,” <i>Mitteikugen der Philomathischen Gessellschaft in Elsasz-Lothringen</i> 4 (1912): 633-667. This was reprinted as C. Mainka, <i>Das bifilare Kegelpendel: (Instrumente für die Aufzeitnung von Erdbeben</i> (Strasburg, 1913).
label: Description
content: “G.U.’s Observatory Finest,” <i>Washington Post</i> (Feb. 27, 1911), p. 2.
place: label: place made
content: France: Grand Est, Strasbourg
setName: label: See more items in
content: Medicine and Science: Physical Sciences
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content: Seismographs
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content: Science & Mathematics
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content: Measuring & Mapping
creditLine: label: Credit Line
content: Georgetown University
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: PH.319816
label: accession number
content: 240152
label: catalog number
content: 319816
objectType: label: Object Name
content: seismograph
physicalDescription: label: Measurements
content: overall: 96 in x 48 in x 60 in; 243.84 cm x 121.92 cm x 152.4 cm