A Generalized Thermodynamic Notation

It has recently been shown by Koenig that, as a result of the symmetry of the fundamental relations of thermodynamics, thermodynamic equations can be grouped into families. In the present paper a generalized notation is described which leads to an elegant method of writing down from one generalized equation all the members of a family; in particular, the signs of the various terms are very easily manipulated. The question of the number of members of a family is considered, and a method is given for obtaining the generalized equation when any one member of a family is known. Finally the extension of the method to problems of capillarity, magnetization, etc., is shown to be very readily carried out.