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Greenwich Reduction Registers, 1835 - 1930

Reference Code: GBR/0180/RGO 127

Scope and Contents

These volumes contain standard forms to aid the reduction of planetary and some stellar observations in preparation for publication. A number of volumes are marked with the names of his assistants at the time such as John Glaisher and Hugh Breen. The material in sections 10-13 concerns stellar observations and, with the possible exception of section 13, appears to have been added at a later date.


  • 1835 - 1930


Conditions Governing Access

Many of these volumes are large and can be awkward to handle.

Biographical / Historical

It is thought these volumes are the preparatory reduction work directed by George Bidell Airy to address the back log in publication of observations (mostly planetary and lunar) made at Greenwich 1750-1830. For this work he was awarded the gold medal and a testimonial from the Royal Astronomical Society in 1846 and 1848 respectively.


89 volume(s) : paper

Language of Materials


Physical Characteristics and Technical Requirements

The volumes have been exposed to damp conditions and show foxing, mould damage and insect damage. There is considerable surface dirt, the bindings are generally loose or broken and there are numerous small losses particularly from the spines.

Immediate Source of Acquisition

Produced or accumulated by the Royal Observatory, Greenwich.


The online catalogue for Janus was compiled from an existing list in February 2010 by Zoe A. Rees, Department of Manuscripts and University Archives. The scope and content description was compiled with reference to the online Dictionary of National Biography entry for Airy ( (accessed February 2010).

Date information

DateText: sections 1-9 and 13 circa 1835-45 (covering observations made 1750-1830); sections 10-12 1897-1930.


Royal Observatory, Greenwich

Finding aid date

2008-11-17 11:42:35+00:00

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.