(Βάττος), a shepherd of Neleus, who saw Hermes driving away the cattle he had stolen from Apollo. The god promised to reward him if he would not betray what he had seen. Battus promised on oath to keep the secret; but as Hermes mistrusted him nevertheless, he assumed a different appearance, returned to Battus, and promised him a handsome present, if he would tell him who had stolen the cattle of Apollo. The shepherd was tempted, and related all he knew, whereupon Hermes touched him with his staff, and changed him into a stone. (Ovid, Ov. Met. 2.688, &c.; Ant. Lib. 22.)
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890