On the Production of Pictures for the Stereoscope, will be found to afford much useful information. The additional woodcut illustrations which have been introduced will be found to render important aid to the amateur. I must acknowledge the ready assistance, in the way of correction and information, which has been afforded me by several of the most practised photographic artists of the metropolis. To Mr. Claudet and Mr. Horne, in particular, I am indebted for many novel and most useful details in the practice of the Daguerreotype and the Collodion processes; and to Mr. Sandford, who has furnished me with many valuable facts relating to the preparation of paper for Photography, I am under many obligations. Those gentlemen who have kindly hastened to supply me with the results of their practice, which is duly acknowledged in the text, will accept my thanks. In conclusion, let me hope that the arrangement of the present volume will be found an improvement upon the former editions, and that this Manual may deserve to maintain its place as a Text-Book on Photography. ROBERT HUNT. LONDON, DEC. 1852. ON THE PHOTOGRAPHIC REGISTRATION OF PHILOSOPHICAL INSTRU- MENTS AND THE MEANS OF DETERMINING THE VARIATIONS OF |