From:
Sir John Herschel
To:
George Biddell Airy
Date:
[25 September 1843]
Source of text:
RGO 6.701.106
Summary:
Gives formula for defining the measure of the scale of an actinometer.
Contributor:
John Herschel Project
Showing 1–6 of 6 items
Gives formula for defining the measure of the scale of an actinometer.
Describes some available glass discs, which might do for making lenses for a large refracting telescope [see GA's 1843-8-30].
Regarding the storage of the Standard weights and measures.
Requires information on an actinometer.
Regarding custody of the Standards.
Makes some suggestions about possible storage places for the United States' standards [see GA's 1843-9-9].