Manchester, in the early 1840s. Manchester was a busy industrial town in these days, actually, it could be named as the industrial cen-ter of England, and in those days, this was synonymous with the industrial center of the world. James Prescott Joule, a young owner of a brewery, was walking towards his factory. Well, actually it was still his father’s factory, but he had taken responsibility some years ago already. While he was walking through the street, he appeared absent minded, and there was a pretty good, even though not that obvious reason for this absentmindedness: His brewery was doing well, actually, the beer he produced was among the most popular ones in the town. However, there was something completely different that puzzled and to some extends troubled Joule. ...

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A Primary Sources

Joule, James Prescott: On the Mechanical Equivalent of Heat, in: Philosophical Transactions of the Royal Society of London 140, 1850, S. 61–82.
Joule, James Prescott et. al.: The Scientific Papers of James Prescott Joule 1884, available online:http://archive.org/details/scientificpapers01joul.

B Secondary Sources

Clagett, Marshall: Critical Problems in the History of Science 1962.
Heering, Peter: On J.P. Joule’s Determination of the Mechanical Equivalent of Heat, The History and Philosophy of Science in Science Education: Proceedings of the Second International Conference on the History and Philosophy of Science in Education 1992.
Kuhn, Thomas S.: Energy Conservation as an Example of Simultaneous Discovery, Critical Problems in the History of Science 1962.
Sibum, Heinz Otto: Reworking the Mechanical Value of Heat: Instruments of Precision and Gestures of Accuracy in Early Victorian England, in: Studies in History and Philosophy of Science Part A 26, Ausgabe 1 (1995), S. 73–106.

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