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Herschel1065

From:
Sir John Herschel
To:
[William Whewell]
Date:
[28 August 1839]
Source of text:
RS:HS 25.5.16
Summary:

Wishes to have mentioned to the Physical Section of the B.A.A.S. that JH has discovered that the extreme red rays [infra-red?] of the sun do not darken photographic paper, but tend to whiten it.

Contributor:
John Herschel Project

Herschel8877

From:
Sir John Herschel
To:
William Whewell
Date:
[28 August 1839]
Source of text:
B.A.A.S. Report for 1839 (1840), pt. 2, 9-11 & Athenaeum, #621 (Sept. 21, 1839)
Summary:

Reports to the B.A.A.S. [through WW as section president] on experiments JH has conducted concerning the photochemical effects of the rays at the far red end of the spectrum.

Contributor:
John Herschel Project
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