Copy letter, from Augustus De Morgan to Joseph Powell, dated at 91 Adelaide Road

Reference number: HS/19/269

Date: 17 February 1863

Description

Copy letter in De Morgan's hand. Comments on two papers likely on optics written by Powell. Confirms the mathematics are correctly managed but the issues is with the number of sines that are required in the formula. Cites Lambcot on photometry and Herschel on light as authorities and references.
Likely forwarded to Herschel for reference.

Reference number: HS/19/269
Earliest possible date: 17 February 1863
Page extent: 2 pages
Format: Manuscript
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Creator name

Augustus de Morgan

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Citation

Augustus de Morgan, Copy letter, from Augustus De Morgan to Joseph Powell, dated at 91 Adelaide Road, 17 February 1863, HS/19/269, The Royal Society Archives, London, https://makingscience.royalsociety.org/items/hs_19_269/copy-letter-from-augustus-de-morgan-to-joseph-powell-dated-at-91-adelaide-road, accessed on 14 February 2026

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https://makingscience.royalsociety.org/items/hs_19_269/copy-letter-from-augustus-de-morgan-to-joseph-powell-dated-at-91-adelaide-road

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This item is part of:

Correspondence of Sir John Frederick William Herschel
1812-1870 Creator: John Frederick William Herschel Reference number: HS
Correspondence of John Frederick William Herschel: volume 19 Miscellaneous
1821-1870 Reference number: HS/19

Related Fellows

John Frederick William Herschel
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Herschel Letters

This collection of nearly 10,900 letters, drafts, copies and notes is the largest repository of scientific correspondence from and to Sir John Herschel, leading figure of Victorian science.

Dates: 1807 - 1875

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