Boyd's Battery

The Boyd's Battery (or Boyd's Miniature Galvanic Battery) is an electrotherapeutic medical pendant, promising to generate a healing electric current in the wearer, produced by the reaction of the varying metals constituting the battery against the skin (as a galvanic response). It was invented by J.C. Boyd, for whom it is named, and first sold in 1878 through Boyd's Galvanic Battery Co.