U.S. Patent No. 575658, Jan 19, 1897
Abraham Mayer, New York City
Electrotherapeutic attachment for eyeglasses. Two separate galvanic circuits were claimed in this patent. The main therapeutic circuit passed through the frame of the glasses and the wearer. The second "local" circuit passed through the wearer only at the point of contact, causing the wearer to sweat, thus increasing the power of the battery. Current was provided by copper/zinc batteries either at the ends of the bows or on the nosepieces.