The earliest known use of an expert witness in English law arrived in 1782, when a court that was hearing litigation relating to the silting-up of Wells harbour in Norfolk accepted evidence from a leading civil engineer, John Smeaton. This decision by the court to accept Smeaton's evidence is widely cited as the root of modern rules on expert witness evidence.
John Smeaton FRS (8 June 1724 - 28 October 1792) was a British civil engineer responsible for the design of bridges, canals, harbours and lighthouses.He was also a capable mechanical engineer and an eminent physicist. Smeaton was the first self-proclaimed "civil engineer", and is often regarded as the "father of civil engineering" He pioneered the use of hydraulic lime in concrete, using pebbles and powdered brick as aggregate. Smeaton was associated with the Lunar Society.
In his 1759 paper "An Experimental Enquiry Concerning the Natural Powers of Water and Wind to Turn Mills and Other Machines Depending on Circular Motion" Smeaton developed the concepts and data which became the basis for the Smeaton coefficient, the lift equation used by the Wright brothers. Smeaton, too is important in the history, rediscovery of, and development of modern cement, identifying the compositional requirements needed to obtain "hydraulicity" in lime; work which led ultimately to the invention of Portland cement. Portland cement led to the re-emergence of concrete as a modern building material, largely due to Smeaton's influence.
https://www.britannica.com/biography/John-Smeaton
https://www.britannica.com/topic/Smeatonian-Society