[This is WHFT's final version of this letter, as published in the Literary Gazette, no. 1160, 13 April 1839, pp. 235-236.]

Fine Arts.
Photogenic Art
[It is with great pleasure we insert the following letters, which continue to unfold discoveries and improvements in an art which may almost be considered as magical, and the importance of whose eventual results it is impossible to over-estimate. Mr. Talbot's, Sir John Herschel's, and Mr. Downing's communications all tend to the same issue, and to complete the elucidation of this engrossing topic.-Ed. L.G.]

Lacock Abbey, Wilts
April 8, 1839

Dear Sir, -

I have the greatest dislike to controversy, which I regard as a complete waste of time. I consider it sufficient to have stated, once for all, in your widely circulated journal, that I discovered the art of obtaining photogenic pictures from glass in the year 1834, along with the other processes, of which it is but a slight variation. It would have been sufficient for me to refer to the seventh section of my first memoir to the Royal Society (published January 31st). But, since that account seemed to have been already in some measure forgotten by the public, I stated it again, and in a fuller manner. How could I do otherwise, when I found that a patent had been applied for for this identical process? I was obliged then to step forward and "claim my own," which I endeavoured to do in the most courteous manner, observing what I sincerely believe) "that I had no doubt that the gentlemen who proposed it imagined it to be a new process, hitherto overlooked." Pressing forward in the ardour of discovery, they did not stop to inquire what had been already achieved.

I should take blame to myself for not having dwelt longer on this particular point, in my memoir to the Royal Society, if it had not been that that memoir was written under circumstances which would have pleaded excuse for much more considerable omissions. For, I beg to recall to your recollection the sudden and unexpected announcement of M. Daguerre's ^<1> discovery in the month of January last; by which I was placed in a very unusual dilemma (scarcely to be paralleled in the annals of science): for I was threatened with the loss of all my labour, in case M. Daguerre's process proved to be identical with mine, and in case he published it at Paris before I had time to do so in London. I was obliged, therefore, to use all possible expedition in drawing up a statement, and exhibiting specimens to the Royal Society. If I had known that M. Daguerre intended to keep his process so long a secret, I would certainly not have written on the subject in so imperfect and hasty a manner. But I had no choice; at least, I thought I had none, which comes nearly to the same thing. But I never supposed for a moment that this memoir would be mistaken for a regular treatise written by me on the Photogenic art, or as containing all the facts which I was acquainted with. In fact, to have detailed all the experiments which I have made on the subject, would have occupied a much longer time than I had at my disposal. Many points were necessarily omitted, or abridged: and, moreover, I had laid down as a rule to myself not to include in my statement to the Royal Society any methods which I had not actually made trial of, however certainly they might seem deducible from the same principles. Thus, for instance, I have said nothing of perhaps the most important application of which the new art is susceptible (that of taking portraits from the life with a camera obscura), because I have not yet accomplished this, although I see no reason to doubt its practicability. And, upon the same grounds, I omitted mention of the process which I am now about to relate: -

Some years ago, a French artist announced that he had discovered a method of increasing or diminishing at pleasure the size of an engraving. This created considerable curiosity, and many conjectures were made concerning the process by which he effect it. But, I believe that the precise means which he employed have not yet been discovered. I suppose that these will one day be made known; in the meanwhile it may interest your readers to know that the photogenic art affords a ready method of obtaining this desideratum, the power of expanding or diminishing a design in any required ratio. I had long contemplated this as an almost certain consequence, from the known properties of the camera obscura. By altering the position of the lens, the image could be made to bear any required proportion to the object; and this image would stamp itself upon prepared paper, in the way which has been already described. Unless, therefore, some very unlooked-for circumstance interfered, I had no doubt of a satisfactory result to the experiment.

The same having occurred to Mr Wheatstone, ^<2> he proposed to dispense with a lens, and to use any radiant point of light. (This simplifies the process of enlarging the design; we lose, however, the power of diminishing it.) However, the best evidence of the possibility of a thing is its actual performance; and this proposed improvement has been successfully accomplished by Sir J. Herschel, ^<3> as you will see by the following extract from one of his letters, which, with his leave, I will transcribe. His experiments were made without knowledge of our contemporaneous speculations.

Extract of a Letter from Sir J. Herschel. ^<4>

"By placing an etching on a smoked glass (not having a resinous ground) behind an aplanatic lens, the smoked side towards the focus, a copy of the etching reduced on any required scale, is obtained. By exposure to a solar beam radiating from the focus of a lens, the scale may be enlarged. The reducing process, on trial, succeeded perfectly, only a little care is required to follow the sun. By the use of highly sensitive paper, this inconvenience would be much diminished; and, by attaching the whole apparatus to an equatorial with a clock, it would be entirely removed. If a resinous ground is used, the etching must be afterwards varnished or gummed, to destroy the loose light refracted obliquely by the thin edges of the cut-up ground, which is never quite opaque. "Slough, March 27."

I have communicated these details of Sir J. Herschel's recent experiments, believe that you will view with interest the important extension which the art of photogenic drawing upon glass is likely to receive,

and remain, dear Sir, &c.
H. Fox Talbot

[draft version, from WHFT's archives:]

Dear Sir

In my mem^r pres^d to the R S (31^st) on P.D. I laid down a rule to myself

Some years ago a F. art^t ann^d y^t he h^d disc^d a methd of incr^g or dim^g at pleas^re ye size of an engrav^g

This created cons^ble curios^y, and many conjectures were made concerning ye prcess by w^h he effectd it. But I believe that ye precise means w^ch he empl^d have never not yet been disc^d.

[illegible deletion] I suppose that these will 1 dy be made known - In the meanwhile, it may interest your readers to know that the Photogenic art affords a ready method of obtaining this desid^m -; the power of expanding

In my mem^r pres^d to the RS on the 31^st Jn, I laid down as a rule to myself, not to speak of describe any applicat^ns of Photoc Draw^g w^ch I had not act^ly tried, however certainly they might seem to be deducible from the same principles - Thus for inst^ce I have said nothing of perhaps the most import^t applicatⁿ of w^ch it is susceptible the possibility (that of taking portraits from the life, with a Cam. Obscura) because I have not yet accomplished it, altho' I see no very great difficulty in the way that ought to be consid^d to prevent its being done of its no reason to doubt its practicality.

And upon y^e same grounds I omittd mentⁿ of the method of expanding or diminish^g a n engrav ^g design a design in any required ratio

I ha ved long contempt^d this as an almost certain conseq^ce from the known pro^ps of the Cam^a Obs^ra By alter^g y^e posⁿ of y^e lens, by which the image may c^d be made to bear any required proportⁿ of the object; and this image w^d stamp s itself upon my prepared paper, in the way w^ch h. been already laid before described. Unless therefore some very unlooked for circ^ce interfered, to present I had no doubt of a satisfacty result f^rm this process to y^e exp^t. -

The same hav^g occ^d to M^r W. he has M ^r Wheatstone has proposed to me to dispense with a lens, and to use any radiant point of light (This simplifies the process of enlarging the design; we lose however the power of diminishing it.) The exp^t here suggestd This exp^t in ye ph art However, the best evid^ce of ye possibility of anyth ^g a thing is its actual perform^ce & this proposed improvem^t

The process have spoke of Which is not yet consid of the matter This improvem^t ye art process

Sir J. H has bⁿ lately successfully accopl^g D by Sir J H it [illegible deletion]

as you will see by the foll^g extract from 1 of his letters

w^ch w^th his leave I will transcribe

His exp^ts were made without knowledge of our contemp^s - speculations

Slough March 27

So far then f^r there being any new

we were occupied

in the more diffic^t

to recondite process, of

Finding I have copied these details of Sir J H's recent exp^ts believing that you will view with interest the singular import^t extension which the art of ph. draw^g upon glass is likely to receive,

It will show to you, that not only

perfectly well acquainted with photogenic drawing upon glass

but that we had advanced some consider distance in a line of new discovery, depending upon it as its basis

---

Notes:

1. Louis Jacques Mandé Daguerre (1787-1851), French artist, showman & inventor.

2. Sir Charles Wheatstone (1802-1875), scientist.

3. Sir John Frederick William Herschel (1792-1871), astronomer & scientist.

4. See Doc. No: 03846.