Displacement Interferometry By The Aid Of The Achromatic Fringes, Part 4 is a book written by Carl Barus and published in 1919. The book is a continuation of a series of works by the author on the topic of displacement interferometry, which is a technique used to measure small distances or changes in position. The book focuses on the use of achromatic fringes, which are interference patterns that do not exhibit color distortion, to improve the accuracy...