Roth's method for the solution of boundary-value problems in electrical engineering

Between the years 1927 and 1938 the French engineer E. Roth developed a powerful method for the solution of boundary-value problems in electrical engineering. He applied the method to problems in heat conduction and magnetic-field problems in electrical machines and transformers, although the application of the method is not necessarily limited to such devices. In spite of its possibilities, the method has been omitted from the standard treatises on electromagnetic problems, because there are certain difficulties associated with it. The paper gives a critical account of the method, listing both advantages and disadvantages and relating these to the physical and mathematical basis of Roth's work.