James Joule was born in Salford, near Manchester, England, on December 24, 1818. He was the second son of a wealthy brewery owner and was educated at home by private tutors. For three years he was fortunate enough to have the eminent British chemist, John Dalton as his chemistry teacher. He never attended a university; as a consequence, while he was bright enough to learn a great deal of physics on his own, he remained, like Michael Faraday, unskilled in advanced mathematics.

Joule had the means to devote his time to what became the passion of his life — obtaining highly accurate experimental results in physics, for which he displayed a precocious aptitude. His genius showed itself in his ability to devise new methods, whenever needed, to improve on the accuracy of his quantitative results.

Joule had no real profession except as an amateur scientist...