THIS volume is addressed to the scientific worker who uses photography as a tool rather than to the specialist in photographic technique or theory. Thus the book is written in a style easily understood by anyone with a rudimentary knowledge of physics and chemistry. It describes the nature of the photographic emulsion, its sensitometry and treatment after exposure in considerable detail. The production of the positive print, colour photography and the camera itself are only described to an extent sufficient to make the book complete. This is as it should be, for the main concern of such a book is to guide the experimenter to find the best possible conditions for obtaining the most satisfactory negative. It is, however, more than a photographic manual, for it contains much interesting information for the reader with only a casual acquaintance with photographic methods.
Eine Einführung in Theorie und Praxis. Von Prof. Dr. E. v. Angerer. Zweite gänzlich neubearbeitete Auflage. Pp. vii + 211 + 3 plates. (Leipzig: Akadem-ische Verlagsgesellschaft m.b.H., 1939.) 13.80 gold marks.