Paper, 'Description of an apparatus employed at the Kew Observatory, Richmond, for the examination of the dark glasses and mirrors of sextants' by G M [George Mathews] Whipple

Description

Whipple writes: 'In the "Proc. Roy. Soc.," for 1867, vol XVI, p. 2, Professor Balfour Stewart described an apparatus designed and constructed by Mr T Cooke for the determination of the errors of graduation of sextants. This instrument has from that date been constantly in use at the Kew Observatory, and since the introduction of certain unimportant improvements, has been found to work very well. No provision was made, however, for its employment in the determination of the errors of the dark shades used to screen the observer’s eyes when the sextant is directed to the sun or moon, and it has been found that errors may exist in the shape of want of parallelism in these glasses, sufficiently large to seriously affect an observation, accurate in other respects.'

Annotations in pencil and ink. Includes one photograph of experimental equipment and an engraving of the photograph.

Subject: Scientific apparatus and equipment

Received 6 February 1883. Read 15 February 1883. Communicated by Warren De La Rue.

A version of this paper was published in volume 35 of the Proceedings of the Royal Society as 'Description of an apparatus employed at the Kew Observatory, Richmond, for the examination of the dark glasses and mirrors of sextants'.

Reference number

PP/3/5

Earliest possible date

1883

Physical description

Ink and graphite pencil on paper

Page extent

6 pages

Format

Manuscript
Print
Photograph