From:
William Henry Fox Talbot
To:
Sir John Herschel
Date:
[19 February 1839]
Source of text:
RS:HS 17.284
Summary:
Describes mediocre results obtained using ferrocyanate of potash for fixing image. Mentions some other methods, including his favorite, common salt. Asks JH to keep these secret.
Contributor:
John Herschel Project