William Derham

William Derham (Stoulton, Worcestershire, 1657 - Upminster, Essex, 1735) was an English clergyman, natural theologian and amateur scientist, elected a Fellow of the Royal Society. He is remembered above all for producing one of the earliest reasonably accurate measurements of the speed of sound, and for his place in the natural theology tradition, which sought to demonstrate the existence and attributes of God from the order of nature.

He studied at Trinity College, Oxford, and was ordained in 1681. After serving as vicar of Wargrave, he became rector of Upminster in 1689, a post he held until his death. From 1716 he was also a Canon of Windsor, and he divided his time between the two places. His books Artificial Clockmaker (1696), Physico-Theology (1713), Astro-Theology (1714) and Christo-Theology (1730) argue from design in the universe. William Paley drew on them nearly a century later for his watchmaker analogy. They also contain genuine observations, such as one of the earliest theoretical descriptions of a marine chronometer.

In 1709 he published a more accurate measure of the speed of sound. He observed a distant shotgun flash from the tower of St Laurence's Church in Upminster, timed the delay to the report with a pendulum, and fixed the distances by triangulation. He also edited the work of John Ray, whose biography he wrote, and published manuscripts by Robert Hooke. His meteorological records from Upminster are among the earliest in England. His example as a parson-naturalist was influential, and his name remains tied to the history of acoustics.