Frederick McKinley Jones

Frederick Jones was born in Cincinnati in 1893 to an Irish father and a Black mother who left when he was small. His father, a railway worker, could not cope, and a Catholic priest took the boy in at about seven. Two years later his father died. He left school at eleven after the sixth grade, swept out a garage, and by fourteen was working as a mechanic. Everything he knew about engines, electricity and machines he taught himself from books and by taking things apart.

In 1912 he moved to Hallock, a small town in the far north of Minnesota, to work as a mechanic on a large farm. He said later that it was a place where a man was judged on ability rather than colour. He served as a sergeant in the First World War, wiring his camp for electricity and telephones, and came back to Hallock, where he built the transmitter for the town\'s first radio station and a device that synchronised sound with film for the local cinema.

That brought him to Joseph Numero, a Minneapolis maker of cinema sound equipment, who hired him in 1927. In 1938 a customer complained of a lorry-load of chickens spoiling in the heat, and Jones designed a compact refrigeration unit that could take the pounding of the road. Numero sold his sound business and the two founded Thermo King. Refrigerated trucks carried food and blood across the Second World War and changed the diet of whole countries.

Jones held 61 patents. He died in 1961 and was awarded the National Medal of Technology posthumously in 1991.