Archives Catalog Entry
Planimeter, Keuffel & Esser
Planimeters were used to measure areas under curves on a paper plot. Greenstein used this one to measure the equivalent widths of absorption lines in the spectra of stars. (information from Judith Cohen; more in file.) Manufactured in Germany by Keuffel & Esser, model number 4242, serial no. 12711. No date. In original black case.
Greenstein, Jesse Leonard (Astrophysicist)
LENGTH: 10 x 3 5/8 in. (case); QUANTITY: 1 instrument with case
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