Science Saturday-William Derham Clergyman of Soundwaves.

Charlie Keeble continues his popular Science Saturday series with a story about how the speed of sound was measured by a clergyman polymath from Upminster in the 18th century.

Last time I told the story of the famed taxonomy naturalist John Ray and towards the end I mentioned the name of William Derham, who was a person friend towards the end of Ray’s life. Derham shared some interest in natural scienceswith Ray and made his own catalogues of the flights of birds and weather recordings. 

William Derham’s story however does not begin in Essex. Now that does not discount his achievements as an Essex scientist because the achievement he made was in Upminster in 1709. You can still call it an achievement by a geographic location even if the scientist does not originate from that location. Alexander Graham Bell invented the telephone in Boston, USA, but he was born and raised in Scotland. 

Derham was born in Stoulton, Worcestershire in 1657 to a poor household. In researching his life story I have little toread from because there is no official biography from his life other than a few obituaries. He attended Trinity College, Oxford and studied theology to become a priest. He was ordained in 1682 to become a priest and was then appointed as a vicar in Wargrave. He later became Rector of St Laurence Church in Upminster in 1689 and held the post all the way to the end of his life. 

Away from his clerical duties Derham found plenty of time to indulge in his scientific, medical and natural history interests. Among his science activities he studied the theological connection between science and nature. Derham contributed many articles to the Royal Society’s own publicationTransactions of the Royal Society using information from hispersonal research work. He covered everything from astronomical events and subjects, weather recordings in Upminster, medicine, and the migration of birds and insects. He even made studies of the geology of Upminster examining the various strata of in a 178 feet deep well dug in Upminster.

Derham’s most famous contribution to science however took place right in the middle of Havering at St Laurence Churchitself. In 1709 Upminster was a hamlet with the church perched on a hill that could see as far away as Woolwich. This gave Derham a vantage point for his telescope based in the church tower where he could see far out in order to make his experiment work. He was making a measure of the speed of sound using the telescope, a half second pendulum as a stopwatch and help from his friends using guns from various locations.

Derham got his friends to fire their guns from these locations and he observed them from St Laurence Church using his telescope. He watched them fire their rifles at a set time and measured the difference between observing the flash of the guns being fired and the time it took for the sound of the gunshot to reach him. Derham measured the time using the half second pendulum and made an average estimate of the speed of sound to be at 1,702 Parisian feet per second. This is a dead system of measurement, but I took the time to convert the measurements. In the UK imperial system it’s 1,143 ft/sec (348.8 metres per second). This is the closest to the most accurate modern measurement of the speed of sound that is1,125 feet per second (343 metres per second). 

As well as making scientific discoveries and contributing to scientific journals William Derham also wrote some books of his own. In 1699 he wrote The Artificial Clockmaker, a book on how the mechanics of watch and clocking making explaining the art of calculating numbers for the component parts of watch making. He also wrote a series of books based on lectures he gave about physico-theology or teleology, which is the study of the being and attributes of God which is a reason for something that serves as a function of it’s ends, it’s purpose or it’s goals. 

His final resting place was in Upminster where he was buried in the grounds of St Laurence in 1735. His exact grave is unknown, but he is lying in rest in the chancel of the church. But there is a plaque that was installed on the church wall in 2011 honouring his achievement in measuring the speed of sound.

William Derham was a clergyman who took a great interest in science and natural history. Many of his works are based upon observations in his adopted county of Essex. He had the research practices of an amateur scientist like a modern day citizen science advocate. I would like to see more people like him take up citizen science activities and report them to the Havering Daily for special scientific purposes just as he did over 300 years ago. You don’t have to be a science graduateor even a geek, just possess some curiosity and observational skills and record what you see in nature that may be interesting.