Thats gotta hurt.

On May 24, 1847 the Dee River bridge collapsed as a train passed over. Five people died and many were injured. The bridge was unusual in that it was made of cast iron. In fact it was made of three large chunks of cast iron strengthened by more cast iron girders.

Anyone that has ever messed with cast iron will know that yes it is hard and heavy, but it is brittle. Makes great frying pans and barbecues though.

The bridge was designed by Robert Stephenson and was finished in the fall of 1846. It was in use about 8 months. It appears the very day of the disaster, Stephenson had extra ballast added to the bridge deck to cover over the wooden ties as a precaution against fire. Fire had recently destroyed a Great Western Railway bridge at Uxbridge.

The extra weight of all that gravel was no doubt a huge factor in the bridge snapping that day. An inquiry was struck to find out the cause and many learned men rubbed their chins thoughtfully. The conclusion was unanimous: cast iron makes crappy bridges. Whether it was stress cracks, bending from overload, or simple bad design, they all agreed not to go there again.

But there still was quite few other cast iron bridges that collapsed, at least six in England alone in the subsequent 30 years. Like I said, makes nice lawn furniture.