ABSTRACT
PROFESSOR CATTELL, in reviewing for Science, in 1898, the second edition of Helmholtz’s Physiologische Optik, said that this work is “one of the few great classics in the history of science”. This very just judgment holds still at the present time, although it is now nearly sixty years since the first edition, which had been some ten years in coming out, was finally issued. Whoever looks over this splendid example of acute scientific thinking and brilliant experimenting will be grateful to the Optical Society of America and to the editor in charge of the translation, Professor Southall, for having decided to bring out even now (what ought to have been done long ago) an English translation of this great work. Some of the facts here recorded will, it is true, have been superseded by later work, but on the other hand much will be found in it which has been, by accident, simply overlooked in later times. The scientist in the subject of physiological optics will therefore be amply repaid if he reads this translation, and not simply secures it for his bookshelves.
