Overall view of the clock mounted on a wall, showing the clock dial, glass dome, the constant, low-pressure chamber.

Images (11)

astronomical regulator, no. 65

Date: 1902

Inventory Number: 1998-1-0190a

Classification: Clock

Subject:

astronomy, time keeping,

Maker: Sigmund Riefler (1847 - 1912)

User: Harvard College Observatory (founded 1839)

Cultural Region:

Deutschland,

Place of Origin:

München,

Dimensions:

Overall: 137 x 37 x 37 cm, 330.7 lb. (53 15/16 x 14 9/16 x 14 9/16 in., 150 kg)

Overall - Storage: 137 x 37 x 37 cm (53 15/16 x 14 9/16 x 14 9/16 in.)

Material:

glass, mercury, brass, alloy,

Accessories: barometer, pump (missing)

Description:

This is a classic Riefler astronomical regulator with constant, low-pressure chamber and the escapement designed by Sigmund Riefler in 1893.

See captions to photos for more details.

In Collection(s)

Signedon dial: S. Riefler München
on dial: 1902
at top of pendulum: RIEFLER / MÜNCHEN

Inscribedon left side of dial: S. Riefler / D.R.P. No. 50739 / No. 65
on right side of dial: München / D.R.P. No. 100870 / 1902

Historical AttributesNumbers engraved on dial refer to Riefler patents:

D.R.P. No. 50739 Riefler "free" pendulum escapement
D.R.P. No. 100870 Nickel-steel alloy ("Invar") pendulum

Riefler also had a patent for a mercury compensation pendulum (D.R.P. No. 60059).

Curatorial RemarksTechnical description provided by Richard Ketchen, horologist, February 2008.

ProvenanceBought by David P. Wheatland from Harvard College Observatory in April 1957.

Related WorksPhilip Woodward, My Own Right Time: An Exploration of Clockwork Design (Oxford: Oxford University Press, 1995).

On Riefler clock works, see the following website.