Leeds to Liverpool Bridge 74A, near Chorley

sketchfab

Bridge 74A on the Leeds and Liverpool canal at Chorley is a late addition, constructed to support the innovative Railway. It plays a significant role in the Wikipedia page about Skew Arch Bridges. Built using Edward Sang's Logarithmic spirals instead of conventional helical ones, it showcases unique engineering skills. This distinctive design is often referred to as "French" coursing, although I'm unsure why this name was chosen, unless masons occasionally used the phrase "scuse my French" when cutting stones. Notably, it is the only stone-built example I know of, whereas there are two brick ones at Cowley Junction in Exeter constructed under William Froude's supervision. This 3D model was created from 375 images taken from the towpath with a 1.5m pole to extend camera reach. As a result, the spandrel facing away from the towpath received insufficient coverage, making it challenging to produce an accurate model.