John Whitehurst FRS (10 April 1713 – 18 February 1788), born in Cheshire, England, was a clockmaker and scientist, and made significant early contributions to geology. He was an influential member of the Lunar Society.
Whitehurst was born in Congleton, Cheshire, to a clockmaker, the elder John Whitehurst. Receiving only a slight formal education, the younger Whitehurst was taught clockmaking by his father, who also encouraged the boy's pursuit of knowledge. At the age of twenty-one, the son visited Dublin to inspect a clock of curious construction of which he had heard. In 1772 he invented the "pulsation engine" (not to be mixed up with a Pulser pump), a water-raising device that was the precursor of the hydraulic ram.
About 1736 Whitehurst entered into business for himself at Derby, where he soon obtained great employment, distinguishing himself by constructing several ingenious pieces of mechanism. Besides other works he made the clock for the town-hall, and in reward was enrolled as a burgess on 6 September 1737. He also made thermometers, barometers, and other philosophical instruments, and interested himself in contriving waterworks. He was consulted in almost every undertaking in Derbyshire and in the neighbouring counties in which skill in mechanics, pneumatics, and hydraulics was required.
In 1774, Whitehurst obtained a post at the Royal Mint in London. In 1775, on the passage of the act for the better regulation oí the gold coinage, without any solicitation on his part he was appointed stamper of the money-weights on the recommendation of the Duke of Newcastle. Whitehurst moved to London, where the rest of his life was passed in scientific pursuits, and where his house in Colt Court, Fleet Street, (formerly the abode of James Ferguson) was visited by other distinguished scientists.
In 1778 Whitehurst published his theory on geological strata in An Inquiry into the Original State and Formation of the Earth. The original design of this work, which he began to prepare while living at Derby, was to facilitate the discovery of valuable minerals beneath the Earth's surface. He pursued his researches with so much ardour that the exposure he incurred tended to impair his health.