From SABR member David Kagan at The Hardball Times on May 12, 2015:
In 1940 a young outfielder by the name of Danny Litwhiler joined one of the worst teams in the history of the National League, the Philadelphia Phillies. From 1940 through 1942 the Phils finished last each year, compiling a combined record of only 135 wins against 323 loses. Yes, that required three consecutive 100-loss seasons.
Despite his dismal team in 1942, Litwhiler accomplished the rare feat of completing the season without a single error, and he was the first ever to do so. For this reason, his glove is in the Hall of Fame. During an interview in 2005, he stated it may have been the first glove on which the fingers were stitched together with rawhide.
Few have disputed his claim. True or not, Litwhiler was a prodigious baseball innovator. In 1956 he created Diamond Grit to dry infield dirt after a rain. In 1962 he was awarded a patent for the batting cage. Finally and to the point, in 1974 he brought the idea of a handheld radar gun to the JUGS Sports company.
We know radar was invented in World War II, but by the early 1970s police were routinely using it to catch speeders. Litwhiler, by then the baseball coach at Michigan State, either read a story about radar use by the campus cops or drove by and saw them using it, or perhaps he was pulled over for speeding. The details are murky.
In any case, he immediately saw the potential of radar as a teaching tool for baseball. He was particularly interested in helping pitchers increase the speed differential between their fastball and change-up. Of course, the JUGS gun has become an indispensable tool for scouts and coaches throughout baseball. The reading from a gun is displayed after ever pitch in almost every major league stadium.
Read the full article here: http://www.hardballtimes.com/the-physics-of-radar-guns/
Originally published: May 12, 2015. Last Updated: May 12, 2015.