the utmost confidence in your ability as a practical man, long engaged in the science of which it treats, as well as your knowledge of the sciences generally; as well as your regard for candor. To you, therefore, I leave the decision whether or no I have accomplished my purpose, and produced a work which may not only be of practical benefit to the Daguerrean artist, but of general interest to the reading public, and your decision will influence me in offering it for, or withholding it from, publication.

If it meets your approbation, I would most respectfully ask permission to dedicate it to you, subscribing myself,

With esteem,
Ever truly yours,
HENRY H. SNELLING

New York, February 1st, 1849.
Mr. H. H. SNELLING.

Dear Sir--Your note of January 27th, requesting permission to dedicate to me your "History and Practice of Photography," I esteem a high compliment, particularly since I have read the manuscript of your work.

Such a treatise has long been needed, and the manner in which you have handled the subject will make the book as interesting to the reading public as it is valuable to the Daguerrean artist, or the amateur dabbler in Photography. I have read nearly all of the many works upon this art that have emanated from the London and Paris presses, and I think the reader will find in yours the pith of them all, with much practical and useful information that I do not remember to have seen communicated elsewhere.

There is much in it to arouse the reflective and inventive faculties of our Daguerreotypists. They have heretofore stumbled along with very little knowledge of the true theory of their art, and yet the quality of their productions is far in advance of those of the French and English artists, most of whose establishments I have had the pleasure of visiting I feel therefore, that when a sufficient amount of theoretic knowledge shall have been added to this practical skill on the part of our operators, and when they shall have been made fully acquainted with what has been attained or attempted by others, a still greater advance in the art will be manifested.

A GOOD Daguerreotypist is by no means a mere machine following a certain set of fixed rules. Success in this art requires personal skill and artistic taste to a much greater degree than the unthinking public generally imagine; in fact more than is imagined by nine-tenths of the Daguerreotypists themselves. And we see as a natural result, that while the business numbers its thousands of votaries, but few rise to any degree of eminence. It is because they look upon their business as a mere mechanical operation, and having no aim or pride beyond the earning of their daily bread, they calculate what will be a fair per centage on the cost of their plate, case, and chemicals, leaving MIND, which is as much CAPITAL as anything else (where it is exercised,) entirely out of the question.

The art of taking photographs on PAPER, of which your work treats at considerable length, has as yet attracted but little attention in this country, though destined, as I fully believe, to attain an importance far superior to that to which the Daguerreotype has risen.

The American mind needs a waking up upon the subject, and I think your book will give a powerful impulse in this direction. In Germany a high degree of perfection has been reached, and I hope your countrymen will not be slow to follow.

Your interesting account of the experiments of Mr. Wattles was entirely new to me, and is another among the many evidences that when the age is fully ripe for any great discovery, it is rare that it does not occur to more than a single mind.

Trusting that your work will meet with the encouragement which your trouble in preparing it deserves, and with gratitude for the undeserved compliment paid to me in its dedication,

I remain, very sincerely,
Your friend and well wisher,
E. ANTHONY.

PHOTOGRAPHY.

CHAP. I.

A BRIEF HISTORY OF THE ART.

As in all cases of great and valuable inventions in science and art the English lay claim to the honor of having first discovered that of Photogenic drawing. But we shall see in the progress of this history, that like many other assumptions of their authors, priority in this is no more due them, then the invention of steamboats, or the cotton gin.

This claim is founded upon the fact that in 1802 Mr. Wedgwood recorded an experiment in the Journal of the Royal Institution of the following nature.

"A piece of paper, or other convenient material, was placed upon a frame and sponged over with a solution of nitrate of silver; it was then placed behind a painting on glass and the light traversing the painting produced a kind of copy upon the prepared paper, those parts in which the rays were least intercepted being of the darkest hues. Here, however, terminated the experiment; for although both Mr. Wedgwood and Sir Humphry Davey experimented carefully, for the purpose of endeavoring to fix the drawings thus obtained, yet the object could not be accomplished, and the whole ended in failure."

This, by their own showing, was the earliest attempt of the English savans. But this much of the principle was known to the Alchemists at an early date--although practically produced in another way--as the following experiment, to be found in old books, amply proves.

"Dissolve chalk in aquafortis to the consistence of milk, and add to it a strong solution of silver; keep this liquor in a glass bottle well stopped; then cutting out from a piece of paper the letters you would have appear, paste it on the decanter, and lay it in the sun's rays in such a manner that the rays may pass through the spaces cut out of the paper and fall on the surface of the liquor the part of the glass through which the rays pass will be turned black, while that under the paper remains white; but particular care must be observed that the bottle be not moved during the operation."

Had not the alchemists been so intent upon the desire to discover the far famed philosopher's stone, as to make them unmindful of the accidental dawnings of more valuable discoveries, this little experiment in chemistry might have induced them to prosecute a more thorough search into the principle, and Photogenic art would not now, as it is, be a new one.

It is even asserted that the Jugglers of India were for many ages in possession of a secret by which they were enabled, in a brief space, to copy the likeness of any individual by the action of light. This fact, if fact it be, may account for the celebrated magic mirrors said to be possessed by these jugglers, and probable cause of their power over the people.

However, as early as 1556 the fact was established that a combination of chloride and silver, called, from its appearance, horn silver, was blackened by the sun's rays; and in the latter part of the last century Mrs. Fulhame published an experiment by which a change of color was effected in the chloride of gold by the agency of light; and gave it as her opinion that words might be written in this way. These incidents are considered as the first steps towards the discovery of the Photogenic art.

Mr. Wedgwood's experiments can scarcely be said to be any improvement on them since he failed to bring them to practical usefulness, and his countrymen will have to be satisfied with awarding the honor of its complete adaptation to practical purposes, to MM. Niepce and Daguerre of France, and to Professors Draper, and Morse of New-York.

These gentlemen--MM. Niepce and Daguerre--pursued the subject simultaneously, without either, however being aware of the experiments of his colleague in science. For several years, each pursued his researches individually until chance made them acquainted, when they entered into co-partnership, and conjointly