This volume is a collection of scholarly articles on the Mach Principle, the impact that this theory has had since the end of the 19th century, and its role in helping Einstein formulate the doctrine of general relativity. 20th-century physics is concerned with the concepts of time, space, motion, inertia and gravity. The documentation on all of these makes this book a reference for those who are interested in the history of science and the theory of general relativity

xi should hope for "first and foremost" from any historical investigation, including his own, was that "it may not be too tedious. " II That hope is generally realized in Mach's historical writings, most of which are as lively and interesting now as they were when they appeared. Mach did not follow any existing model of historical or philosophical or scientific exposition, but went at things his own way combining the various approaches as needed to reach the goals he set for himself. When he is at his best we get a sense of the Mach whom William James met on a visit to Prague, the Mach whose four hours of "unforgettable conversation" gave the forty year old, well traveled James the strongest "impression of pure intellectual genius" he had yet received, and whose "absolute simplicity of manner and winningness of smile" captivated him completely. 12 Consider, for example, the first few chapters of this book, Principles of the Theory of Heat, which Mach devotes to the notion of temperature, that most fundamental of all thermal concepts. He begins by trying to trace the path that leads from our sensations of hot and cold to a numerical temperature scale.

Dr Bradley's aim is to provide a work which will introduce readers to the philosophical standpoint employed by Mach in his expositions of physics. The author shows how Mach traces out the evolution of the metrical concepts of heat and mechanics, and includes a discussion of his reformulation of Newton's dynamical principles. Mach's view that we have a semi-awareness of both time and temperature is considered: there is no 'Mach Principle' in Mach's writings; the use of the term by Einstein and others has led to confusion, which the author attempts to remove. The newcomer to the philosophy of science is led to an insight into the methods of one who has had a major influence on the subject.