The fourth and last edition of this book was published in 1967. Although it has been out of print for many years it is still considered the "Bible" of contact theory and is referred to in almost every scientific paper dealing with electric contacts. This classic book serves as a basis for understanding of contacts and their use in technology. It contains fundamental theory, critical information and a richness of details including a pertinent literature list. A chapter is devoted to the tunnel effect, several chapters treat such friction and wear phenomena which are closely connected with the theory of electric contacts. Subjects covered include tarnishing of contact material, fritting of tarnish films in contacts, material transfer in switches and commutation, and the theory of thermal contacts.

This book is a completely revised and rewritten edition of "Electric Contacts Handbook" published in 1958. A large number of new in vestigations are considered, and many of the basic theories are revised in detail and even in general. The body of information had to be limited as it was not advisable to increase the volume of the book. In particular, no attempt was made to cover all of the practical applications. They appear as examples following concentrated explanations of basic phenomena. As in several branches of technology, the solutions of problems ari sing in the field of electric contacts involve insight into various disci plines of physics. It is feit that reviews of some of those topics, especi ally adapted to electric contact phenomena, are welcome to many readers. For example, chapters have been devoted to the structure of carbon, the band theory of electric conduction in solids, certain pro blems in statistics, and the theory of the electric arc. As regards arc problems, new ideas have been introduced. In order to make the main text less cumbersome, such reviews are presented as appendices. Throughout this edition, the mksa-unit system is used in accord with the latest recommendation for standardization of units in scientific and technical writings. The chapter "History of Early Investigations on Contacts" forming Part IV in the preceding edition of 1958 has not been repeated in this book."

Circuit breakers, relays, terminals, microphones, current collectors and commutators, all operate with electric contacts. Industry is making extensive use of contacts with ever-increasing demands on efficiency. The need of up to date reliable theories as well as of formulas and tables for applications is becoming pressing. This book is an attempt to meet this need. As is the case in many other branches of technology today, problems which arise in the field" of electric contacts involve insight in various other disciplines of physics, including parts which have not yet developed to such an extent that they. are treated in elementary text books. Con sidering the lack of introductions to some topics of this kind it is felt that orienting chapters, for instance, on the tunnel effect, the theory of the arc, the structure of carbon, and the band theory of electric conduction in solids might be valuable for many readers. In order not to burden the main text with such chapters they have been presented as appendices. Several chapters have been devoted to the theory offriction and wear."