The first mechanical chess clock was invented by Thomas Wilson in 1883. Prior to that, sandglasses were used. Sandglasses were first used in London in 1862. The first U.S. patent for a chess clock was issued in 1884 to Amandus Schierwater. The present day push-button clock was first perfected by Veenhoff in 1900. The first electronic chess clock was manufactured in Kiev in 1964.