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Papers on the New Altazimuth Instrument, 1881 - 1920

Reference Code: GBR/0180/RGO 7/36

Scope and Contents

Tables showing 'the difference in the values of the runs of the microscope - micrometers as found from observations made during the day and during the night', 1888-1889.

Correspondence with Troughton and Simms regarding the supply of an eyepiece and the supply of a long focus lens for the altazimuth instrument, 1889.

Correspondence with J.G. Loughborough requesting six 6" cannon balls to raise the Altazimuth Dome 1" higher, 1889. There is also correspondence with the Admiralty.

Tables showing the determination of values of the level scales of the levels of the altazimuth by various methods, 1888-1890.

Tables of an examination of the altazimuth level scales and the difference of autumnal measure values of a division of zenith distance levels, 1890-1891.

Corrections to assumed values of divisions of the level scales of the altazimuth deduced from measures made 28-29 May 1890.

Determination of the values of the level scales of the levels of the altazimuth and comparison of results, 1800 and 1891.

Comparison of the change of zero of the altazimuth with those of the circle readings, 1888-1889.

Repairs required to the altazimuth instrument, 1883.

'Circle readings for marks', undated.

Note on a cut in the vertical circle, 25 May 1889.

The history of the altazimuth marks, 1881-1889.

Reduction of the zenith distance of Pollux for clock error, 1888.

Note to the effect that the altazimuth field lens eyepiece was renewed, 1893.

Note to the effect that the altazimuth instrument wires were broken and replaced, 1893.

Note of the system of wires in use in the New Altazimuth Instrument from 26 September 1901 to 1920.

Correspondence with Troughton and Simms regarding a proposed alteration to the eye-end of the New Altazimuth Instrument, 1911-1913.

Miscellaneous memoranda to staff concerning the New Altazimuth Instrument, 1894-1901.

Correspondence with Troughton and Simms regarding improvements to be made to the mercury trough of the New Altazimuth Instrument, 1910-1911.

Correspondence with Troughton and Simms concerning improvements, adjustments and repairs to the New Altazimuth Instrument, 1899-1909.


  • 1881 - 1920

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1 bundle(s) (1 bundle)

Language of Materials


Former / Other Reference


Finding aid date

2006-03-30 10:40:28+00:00

Includes index.


Repository Details

Part of the Cambridge University Library Repository

Cambridge University Library
West Road
Cambridge CB3 9DR United Kingdom

The UK Archival Thesaurus has been integrated with our catalogue, thanks to Kings College London and the AIM25 project for their support with this.