185 
“ Twenty-three specimens of photographs made by Sir J. Her- 
schel accompany his paper — one a sketch of his telescope at 
Slough, fixed from its image in a lens.” 
This is the image above mentioned as having been taken on 
Jan. 30, 1839 — and was, I believe, the first picture ever fixed 
from an optical image ever taken in this country — at least I have 
heard of none earlier. 
At the time of making these experiments, as already mentioned, 
I had no knowledge of M. Daguerre’s process further than the 
mention of the existence of a process (a secret one) in a note 
from Admiral (then Captain) Beaufort some time about Jan. 23, 
1839. Of course I used paper, not silver — and it was not a 
suggestion, but a regular and uniform practice to use the hypo- 
sulphite — I never used anything else. 
I am, Sir, your obt. servt., 
J. F. W. HERSCHEL. 
In reference to the subject of fixing the photographic 
image I find the following passage in a paper read before the 
Royal Society on January 31, 1839, by Mr. Talbot. After 
referring to the improvements of Wedgwood and Davy in 
1802, and the difficulties they found in making the paper 
sufficiently sensible to receive the impression in a camera 
obscura, and their inability to fix the pictures, the author 
states that ct his experiments were begun without his being 
aware of this prior attempt ; and that in the course of them 
he discovered methods of overcoming the two difficulties 
above related. With respect to the latter he says that he 
has found it possible by a subsequent process so to fix the 
images or shadows formed by the solar rays that they become 
insensible to light and states that he has exposed 
some of his pictures to the sunshine for the space of an hour 
without injury.” 
In the abstract of the paper given in the Proceedings the 
method adopted for fixing the image is not stated ; but in a 
paper read before the same Society on February 21 of the 
