From The Indianapolis Star, Friday, August 29, 1924: Officials of Indianapolis amateur baseball organizations have been invited to attend a demonstration of a baseball pitching machine that will be given tonight. Benjamin L. Blair, of Indianapolis, who invented the machine, has trained batters on the New York Yankees and New York Giants teams. He says the machine will do more than a human arm can do in pitching “in” and “out” curves, “drops, and “fadeaways;” it primarily is a trainer of eyes. A graduate of Purdue University’s school of engineering, Blair worked with compressed air machinery and conceived of the idea during the World War of using compressed air for a hand grenade projector, however the government wasn’t interested. In 1922, he received a patent on a machine using compressed air that could eject baseballs at any rate of speed.