That taste can be elicited by electrical stimulation has been known since the time of Sulzer (1795) who stimulated his own tongue with a piece of silver and a piece of lead. Because the idea of electricity had not yet been developed, Sulzer attributed the taste to a vibration of the metals which then stimulated the taste nerves. In spite of numerous investigations, the exact mechanism of electrical stimulation is still in some doubt. Early experiments by von Humbolt, Fabbroni, and by Carlisle (Dzendolet, 1962, p. 303) with non-reversible electrodes were indirectly eliciting a receptor response with products of the electrolysis of saliva and extracellular and intracellular fluids, as was demonstrated by von Zeyneck (1898). This type of stimulation, as well as that obtained with a reversible electrode, has been explained by Dzendolet (1962). In neither case can it be demonstrated that there is direct stimulation of the receptors or nerve fibers.