The Rennies were a Scots family that epitomises the connectivity of civil and mechanical engineering.
I begin, though, with the father of civil engineering, John Smeaton, who is best known for rebuilding the Eddystone Lighthouse during which he discovered that the property of hardening whilst submerged in water was linked to the clay content of the cement. In 1824, a Leeds stonemason, Joseph Aspdin, took this a stage further and invented a method of making from limestone and clay a cement which he called Portland Cement given the similarity in colour between it and Portland stone.
Smeaton, born in 1724 in Austhorpe near Leeds, began as a mathematical instrument maker, as did James Watt. Smeaton then went on to design some sixty water and wind mills. He pioneered the use of cast iron pipes. His civil engineering projects included canals and bridges. He founded the engineering society which became the Institution of Civil Engineers.
Thomas Telford was younger born in 1757 near Lockerbie. He began as a stone mason working on Somerset House in London and then a number of restoration projects. He is know for many civil engineering masterpieces.
He built some 1,200 miles of well drained roads in Scotland. He built the Ellesmere canal and worked on many harbours and bridges. He championed the use of Roman cement, the forerunner to Portland.
John Rennie senior was born in East Lothian in 1761 and was soon fascinated by all things mechanical. He worked for Andrew Meikle a millwright who invented the mechanical thresher. He attended the University of Edinburgh and then set off to explore canals. He was introduced by his university professor to James Watt and went to work for Boulton & Watt, his first project being the installation of steam engines at the Albion flour mills in Southwark. From there he set up his own business making food manufacturing machinery.
Canal mania caught up with him and he produced magnificent civil engineering structures including the Caen Hill flight of locks on the Kennet and Avon canal. He went on to design docks including the East and West India docks and bridges including Waterloo and Southwark bridge.
His son George took over the mechanical engineering side of the business eventually becoming fascinated by the mechanics of the screw propellor and he built a number of ships so powered for the navy
The civil engineering business was left to his son John who completed his father’s projects including London Bridge. He went on to design major drainage projects and was involved with railway building. He became president of the ICE in 1845 and received a knighthood for his services.
Both sons were part of the G and J Rennie shipbuilding yard at Greenwich.
John senior’s youngest son was named Matthew Boulton Rennie perhaps underlining the connections.
Further reading:
https://www.ice.org.uk/what-is-civil-engineering/meet-the-engineers/
.jpg)
