The difference in function of Claude-Nicolas Ledoux’s river surveyor’s house and Abraham Darby Coalbrookdale bridge

When Abraham Darby created the Coalbrookdale bridge over the river Severn the form clearly expresses the function of the bridge, just as had been for centuries before it had the typical structure of what a bridge should look like. “Traditional in its arch form, it was made of five half-arches on each side (ten pieces in all), with a total clear span of 100 feet (30.5 m).Each 50-foot (16.2 m) half-arch was cast as a single piece, a formidable job of iron casting.” (Roth 2007). These thin arches created the impression a rigid yet lightweight looking structure. These revolution iron members created a 100 feet bridge in a single arch whereas by using typical masonry methods needed thick load bearing elements, that could only span a certain distance. This meant that more arches were needed to create a bridge with an equal span which in turn meant that the construction time of the bridge was vastly longer. These iron half arches could be prefabricated and assembled on site very easily. This was considered to be very modern for its time because up until then no one had been able to create a bridge with so little material, in such a short time, that could span that distance. This new type of iron was revolutionary and key to the success of this bridge.

Claude-Nicolas Ledoux’s design, of his unrealised project for the river surveyor’s house on the river Loue, used an abstract form to express the function. “The house is a hollow cylinder lying on a cradling base; through the hollow of the cylinder the river flows, as dramatic an expression of control of the water as Ledoux was able to make.” (Roth 2007). His use of grandeur and expressing the heights of all his designs is again portrayed in this conceptual sketch. In the foreground you can see a previous water wheel, which is miniscule in size. He continues this geometric cylindrical shape in his design and uses symbolism to represent the function. The water rushing through the open void in the building suggests that the function of it must have something to do with the water.

Ledoux used grandeur to emphasise the importance of the inhabitants that occupied the building, just as when he was designing the Royal Saltworks at Arc-et-Senans. He designed the administrators house to be huge as he was the most important occupant in the well structured work city. “The stark geometry of the administrator’s house was emphasized by over scaled details, particularly the columns of the portico built up of alternated cylindrical and square blocks of stone.” (Roth 2007).

His design was ahead of its time, I think, because I don’t think people could picture a building of this scale being built, just as many of his other unrealised projects like his cenotaph for Isaac Newton. The open spaces were just to vast and daunting, the public could not conceive how a building so big and solid would look in its surroundings.