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Harrison MS on Clock No. 1, 1985

Reference Code: GBR/0180/RGO 35/131

Scope and Contents

Photostats of a manuscript written by John Harrison in 1730 concerning the construction of his first marine chronometer. The document describes the problem of finding longitude at sea, the solution of using a marine timekeeper, the accuracy of contemporary clocks, errors in pendulum regulators and their correction, and the effects of temperature on clocks. It continues with notes on the construction of Harrison's chronometer, including the theory employed and compensations introduced. There are two diagrams at the end.


  • Creation: 1985


Conditions Governing Access

From the Management Group:

Unless restrictions apply, the collection is open for consultation by researchers using the Manuscripts Reading Room at Cambridge University Library. For further details on conditions governing access please contact Information about opening hours and obtaining a Cambridge University Library reader's ticket is available from the Library's website (


1 volume(s) (1 volume)

Language of Materials


Immediate Source of Acquisition

Presented by the Worshipful Company of Clockmakers, 19 July 1985.

Existence and Location of Originals

The original manuscript is in the possession of the Worshipful Company of Clockmakers.

Finding aid date

2007-01-30 14:14:16+00:00

Includes index.

Repository Details

Part of the Cambridge University Library Repository

Cambridge University Library
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Cambridge CB3 9DR United Kingdom