Since the first edition of this book was written there has been a good deal of progress in stereoscopy, notably in its commercial and scientific applications; there has also been a number of important developments in connection with the apparatus used for stereoscopic methods and photography. The present edition has been partly re-written and extended to bring it up to date in these respects; no less than 94 pages have been added for this purpose. Whilst amateur stereoscopic photography has not made any noticeable progress in this country, there is still an appreciable number of keen workers enthusiastically pursuing this fascinating branch of photography. On the Continent, however, there is much more interest taken by the amateur in this work. The use of commercial stereoscopic photographs has extended considerably in recent years and many travelers representing commercial firms now carry round a stereoscope and set of photographs to illustrate their firm's products-instead of taking samples or flat photographs. One large electrical concern has found it profitable to have most of its spare parts photographed stereoscopically and the complete set of views sent to all its agencies in different parts of the world. Many of the earliest books, particularly those dating back to the 1900s and before, are now extremely scarce and increasingly expensive. Pomona Press are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.