The regeneration of the electromotor force E of the electric piles formed by two amalgam fillings was measured as a function of time t after the moment of interruption of the short contact of their poles. The measurements were carried out in 30 patients at a mean age of 27.0 +/- 08 years. Automatic recording of the equation E = f (t) demonstrated that in the first phase of from several to about a score of seconds the E value rose rapidly, while in the second phase lasting from several scores to over a thousand seconds the E value approached asymptotically its initial value Eo.