ABSTRACT
The fundamental principles of Hertz’s theory are so simple and so admirable that it seems worth while to expound them briefly. His object, like that of most recent writers, is to construct a system in which there are only three fundamental concepts, space, time, and mass. The elimination of a fourth concept, such as force or energy, though evidently demanded by theory, is difficult to carry out mathematically. The special laws, other than the laws of motion, which regulate any particular system, are for Newton laws concerning mutual accelerations, such as gravitation itself. For Hertz, these special laws are all contained in the geometrical connections of the system, and are expressed in equations involving only velocities.
