Description
|
Ironbridge Tollhouse is one of the ten Ironbridge Gorge Museums.
Follow in the footsteps of millions of tourists who, since 1779, have journeyed to marvel at the world’s first cast-iron bridge.
From Wikipedia, the free encyclopedia
Opened in 1781, it was the first arch bridge in the world to be made of cast iron, and was greatly celebrated after construction owing to its use of the new material.
Design
The bridge is built from five cast iron ribs that give a span of 30.6 metres (100 ft). Exactly 378 long tons 10 cwt (847,800 lb or 384.6 t) of iron was used in the construction of the bridge, and there are almost 1700 individual components, the heaviest weighing 5.5 long tons (5.6 t). Components were cast individually to fit with each other, rather than being of standard sizes, with discrepancies of up to several centimeters between 'identical' components in different locations.
Decorative rings and ogees between the structural ribs of the bridge suggest that the final design was of Pritchard, as the same elements appear in a gazebo he rebuilt. A foreman at the foundry, Thomas Gregory, drew the detailed designs for the members, resulting in the use of carpentry jointing details such as mortice and tenon joints and dovetails.
Two supplemental arches, of similar cast iron construction, carry a towpath on the south bank and also act as flood arches. A stone arch carries a small path on the north, town, bank. |