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The Instrument Collection

Boy Viewing StarsThe Ladd Observatory houses a 12" refracting telescope with a lens made by John A. Brashear of Pittsburgh following the lens design of Prof. Charles S. Hastings of Yale University. The equatorial mounting and mechanical clock drive were made by George N. Saegmüller of Washington D.C. The telescope is equipped with a filar micrometer, spectroscope, and other attachments.

There are also transit telescopes, precision pendulum clocks, chronometers, and various minor instruments. The links below are to images of the instrument makers' marks and indicates that the timepiece is located in the main clock vault. This is only a partial list of the many historic instruments in the Ladd Observatory collection.

Astronomical Clocks & Regulators


  • Warner & Swasey, Cleveland, Ohio (1890)


Transit Instruments

  • 2 ¼" (maker unknown)
  • 2 ½" (maker unknown)
  • 50mm Parkinson & Frodsham, Liverpool
    (ca. 1838) Status: restoration in progress.
  • 80mm Saegmüller, Washington D.C.
    (1890; can also be used as a zenith telescope)

Education & Outreach

Some of the scientific instruments are on display and may be seen on Tuesday evenings when the Observatory is open to the public for telescope viewing.