Hindley's pyrometer and three expansion tubes made by Henry Hindley, York, 1752.
The eighteenth-century lecturer on experimental philosophy, Stephen Demainbray, used this instrument to measure the expansion of various types of metal when heated. The metal bar to be tested was fitted across the base and was heated by a series of wicks floating in oil. The expansion of the metal moved the pointer round the dial. Henry Hindley, who designed it, was an instrument maker from York.