John Southern (c.1758–1815) was an English engineer, son of Thomas Southern of Derbyshire. In 1796 he and his employer James Watt co-invented the Indicator, an instrument for measuring and recording the pressure inside a steam engine cylinder through its stroke. This data was crucial for assessing an engine's efficiency. Southern became a partner of the firm of Boulton & Watt in 1810. The use of the instrument was kept as a trade secret for a generation, only becoming public in the 1830s.
References
- ^ H. W. Dickinson (31 October 2010). James Watt: Craftsman and Engineer. Cambridge University Press. pp. 131–. ISBN 978-1-108-01223-2.
- Baird, Davis (2004). Thing knowledge: a philosophy of scientific instruments. University of California Press. p. 170. ISBN 978-0-520-23249-5.
- M. Norton Wise (March 1997). The Values of Precision. Princeton University Press. p. 231. ISBN 0-691-01601-1.
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