The Dee Bridge, whose cast- and wrought-iron design followed common practice for the period, collapsed under a passing train, killing everyone aboard. Subsequent investigation revealed that the structure, the longest of its kind, simply pushed the limits of railroad-bridge engineering too far.
1847年，英格兰切斯特发生了英国铁路扩建工程的首次重大结构事故。按照当时流行的锻铸方法修建的迪桥（Dee Bridge）在火车开过时突然坍塌，所有乘客全部遇难。随后的调查显示：该桥的锻铸构造在同类桥中历史最为悠久，超出了铁路桥技术所能允许的最大限度。