From:
George Biddell Airy
To:
Sir John Herschel
Date:
[4 November 1867]
Source of text:
TxU:H/M-0643.1 (C: RGO 6.359.537)
Summary:
Provides JH with best definition that GA has available for the gallon [see JH's 1867-11-3], noting that methods for establishing standards are revised, even if the standards supposedly are not.
Contributor:
John Herschel Project