Skip to main content
  • Utility Menu
  • Search
Harvard Logo
HARVARD.EDU

Collections Menu
  • Waywiser
  • People
  • Bibliography
  • Exhibitions
  • Thesaurus
  • My Object Lists
  • About
  • Sign in
Advanced Search
  • Home
  • Objects
  • astronomical regulator
  • Images (36)

astronomical regulator

Overall view of the entire clock.
  • Images (36)

astronomical regulator

Date: 1832
Inventory Number: 2500
Classification: Clock
Subject:
astronomy, time keeping, railroad,
Maker: Simon Willard, Jr. (1795 - 1874)
Maker: Charles Crane Crehore (1793 - 1879)
User: William Cranch Bond (1789 - 1859)
User: George Phillips Bond (1825 - 1865)
User: Harvard College Observatory (founded 1839)
Cultural Region:
United States,
Place of Origin:
Boston,
Dimensions:
207 x 29.5 x 48.5 cm (81 1/2 x 11 5/8 x 19 1/8 in.)
Material:
mercury, walnut, brass, steel,
Accessories: winding key
DescriptionAstronomical regulator in a Boston-made case with a round top and glazed, break-arch top to the trunk door. The regulator dial is silvered brass with a matte, "white" finish. A removable wooden box covers the movement inside the clock's hood to protect it from dust.

The works are of high quality and made to chronometer standards. It has a Graham deadbeat escapement. The pallets are jeweled with thin slips of sapphire, which are unusual for an American clock of this period. The movement has Harrison's maintaining power.

The beat adjustment is built into the pendulum. The steel pendulum rod holds an extraordinarily large jar of mercury (11.5 cm in diameter and 19 cm high) used for temperature compensation.

Electrical contacts were later fitted to the escape wheel and pallet arbor in order to take time signals from the clock. A telegraph key is attached to the inside of the case on the proper right side of the trunk.

The winding key is brass with an ivory handle.

For further details, please see the captions to the photographs.
In Collection(s)
  • Exhibit 2005--CHSI's Putnam Gallery
  • Clocks and Watches
Signedon dial: SIMON WILLARD JR. / BOSTON.
Historical AttributesThis regulator was made in 1832 by Simon Willard Jr., and housed in a case made by Charles C. Crehore. The binding posts for electrical contacts were added later.

It is not known precisely when it first came to Harvard. William Cranch Bond does not mention it explicitly as a clock that he brought with him in 1839 at the time he was appointed Astronomical Observer. After the Observatory was completed on Garden Street in 1847, the clock could have been set up there. Being checked daily against astronomical transits, it might then have provided standard time to New England railroads until 1857. It was then replaced by a Bond & Sons regulator (no. 312) in mid-century.

The use for standard time by Harvard is uncertain and iffy. We might ask why would Bond prefer a Willard clock rather than one from his own business, as he undoubtedly did later. Secondly, the only documented connection of the clock with Harvard is in 1894, when Z. A. Willard, Simon's Willard's son, presented the regulator (back?) to the Harvard College Observatory, where it was kept in use until 1949.
Curatorial RemarksTechnical description provided by Richard Ketchen, horologist, February 2008.
The book on the Willards says that the case is mahogany.
Published ReferencesJohn Ware Willard, Simon Willard and His Clocks (New York: Dover Publications, 1968), plate 25.

Choose Collection

Create new collection

facebook iconTwitter Logo

_______________________________
Join Our Mailing List I Contact
_______________________________
The Collection of Historical Scientific Instruments
Science Center, Room 371 • 1 Oxford Street
Cambridge, MA 02138 •chsi@fas.harvard.edu
p. 617-495-2779 •
f. 617-496-5794
_______________________________
The CHSI is one of the

HMSC Logo

Exhibition Hours

The Putnam Gallery
(Science Center 136):
Monday through Friday, 11a.m. to 4p.m.


The Special Exhibitions Gallery
(Science Center 251):
Monday through Friday, 9a.m. to 5p.m.


The Foyer Gallery
Closed for Installation.

All galleries are closed on University Holidays.

Admission is free of charge.
Children must be escorted by an adult.

Admin Login
OpenScholar
Copyright © 2017 The President and Fellows of Harvard College | Privacy | Accessibility | Report Copyright Infringement

Choose Collection

Create new collection