Otto Hehner (1853-1924) was a leading British analytical chemist who became an important figure in the movement to halt the adulteration of food, particularly through the work of the Society of Public Analysts (SPA). The SPA had been founded in 1874, shortly after the 1872 Adulteration Act, to provide public analysis with institutional and profesional backing, and its journal, The Analyst, first appeared in 1876. The SPA's first task was to actually define adulteration and then to outline a practical system of food inspection and analysis. Hehner became President of the SPA in 1893 and gave his name to Hehner's number: 'The weight or percentage of the nonvolatile fatty acids yielded by 5 g of a saponified fat or oil.'
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