This Short Course o f Theoretical Mechanics is designed for students of higher and secondary technical schools. It treats of the basic methods of theoretical mechanics and spheres of their application along with some to­ pics which are of such importance todays that no course of mechanics, even a short one, can neglect them altogether. In preparing the original Russian edition for translation the text has be­ en substantially revised, with additions, changes and corrections in practi­ cally all the chapters. Most of the additions are new sections containing supplementary infor­ mation on the motion ofa rigid body about a fixedpoint (the kinematic and dynamic Euler equations) and chapters setting forth the fundamentals of the method of generalized coordinates (the Lagrange equations), since the de­mands to the course of theoretical mechanics in training engineers of diffe­rent specialities makes it necessary to devote some space to this subject even in a short course. Also the book presents an essential minimum on the elementary theory of the gyroscope and such highly relevant topics as motion in gravitational fields (elliptical paths and space flights) and the motion of a body of va­riable mass (rocket motion); a new section discusses weightlessness. The structure of this book is based on the profound conviction, born out by many years of experience, that the best way of presenting study mate­ rial, especially when it is contained in a short course, is to proceed from the particular to the general. Accordingly, in this book, plane statics comes be­ fore three-dimensional statics, particle dynamics before system dynamics, rectilinear motion before curvilinear motion, etc. Such an arrangement helps the student to understand and digest the material better and faster and the teaching process itself is made more graphic and consistent. Alongside with the geometrical and analytical methods of mechanics the book makes wide use of the vector method as one of the main generally accepted methods, which, furthermore, possesses a number of indisputable advantages. As a rule, however, only those vector operations are used which are similar to corresponding operations with scalar quantities and which do not require an acquaintance with many new concepts. Considerable space—more than one-third of the book—is devoted to examples and worked problems. They were chosen with an eve to ensure a clear comprehension of the relevant mechanical phenomena and cover all the main types of problems solved by the methods described. There are 176 such examples (besides worked problems); their solutions contain instruc­tions designed to assist the student in his independent work on the course. In this respect the book should prove useful to all students of engineering, notably those studying by correspondence or on their own. The numeration of the equations of each of the four parts is separate; therefore, references to equations are only by their numbers. References to equations in other parts are given with the number of the respective section.