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.