On July 12, 1940, Cincinnati native Frederick McKinley Jones was granted a patent for an automatic refrigeration system for long-haul trucks. Jones - who eventually held more than 60 patents - is considered the nation's most prolific African-American inventor. The roof-mounted truck cooling device he invented in 1935 was adapted to ships and trains and revolutionized the food-shipping industry.

Jones grew up an orphan and had only a sixth-grade education. He was hired as a garage mechanic at 16. Largely self-taught, he also developed a gasoline engine for race cars. Among his other inventions are a portable X-ray machine, and a ticket-taking device for movie theaters.

In 1991, 30 years after his death, Jones became the first African-American inventor to receive the National Medal of Technology.

Rebecca Goodman

E-mail rgoodman@enquirer.com or call (513) 768-8361.