The rotary ial is a device mounted on or in a telephone or switchboard that is designed to send interrupted electrical pulses, known as pulse dialing, corresponding to the number dialed. The early form of the rotary dial used lugs on a finger plate instead of holes. A patent was filed on August 20, 1896 by employees of Almon Strowger, namely, A. E. Keith and the brothers John and Charles Erickson. The Patent No. 597,062 was granted on January 11, 1898.