Search: Herschel, John in correspondent 
Forbes, James David in correspondent 
Herschel, John in author 
1840-1849::1842 in date 
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Showing 15 of 5 items

From:
Sir John Herschel
To:
James David Forbes
Date:
1842-4-9[?]
Source of text:
St. Andrews 21? (C: RS:HS 22.115)
Summary:

Instructions for preparing liquid for the actinometer. Describes 'very strange' experiments on the spectrum as well as an 'unusual' cloud formation.

Contributor:
John Herschel Project
From:
Sir John Herschel
To:
James David Forbes
Date:
[1842-5]
Source of text:
St. Andrews 43?
Summary:

Proposes meeting times in town. Suggests that JF observe the upcoming total eclipse astronomically. Agrees with JF's seemingly 'cold &c' circular on scientific partnerships, while regretting that it needed to be written.

Contributor:
John Herschel Project
From:
Sir John Herschel
To:
James David Forbes
Date:
16?] May [1842
Source of text:
St. Andrews 49
Summary:

Sets up approximate meeting time, depending on his family's timely departure to Antwerp, with JF at the R.S.L. apartments.

Contributor:
John Herschel Project
From:
Sir John Herschel
To:
James David Forbes
Date:
[2 June 1842]
Source of text:
St. Andrews 55 (C: RS:HS 22.122)
Summary:

Compares actinometric measurements of radiation. Explains interest in total eclipse relative to actinometry. Discusses the possibility of making actinometric measurements by photographic means.

Contributor:
John Herschel Project
From:
Sir John Herschel
To:
James David Forbes
Date:
[15 November 1842]
Source of text:
RS:HS 25.6.15 (C: TxU:H/L-0159; Reel 1054)
Summary:

Received JF's paper on 'thermographic process.' Believes that thermic rays were responsible for experimental results of JF, J. W. Draper, and Ludwig Moser. JH's theory of and experiments with thermic rays, which are different from 'calorific' and visible rays, in solar spectrum.

Contributor:
John Herschel Project