Lisbon City, Portugal, Earthquake and Tsunami

To ensure against the collapse of buildings in an earthquake, the new prime minister did several things. First, he arranged to have models of buildings drawn to scale and then arranged for army units to parade backwards and forwards with their horses around the models to find out if their weights and activities affected the models in any way. As the design of new buildings progressed he finally settled on a new kind of structure consisting of a flexible wooden skeleton around which masonry walls would be built. The idea was that the flexible skeleton would be firmly anchored in order to hold the masonry walls in place during an earthquake. At the same time, the masonry would protect the wood from catching fire. This was perhaps the first occasion when a building design was carefully related to the effects of the earthquake. It may have been the first anti-earthquake building system ever designed. Such systems became fixed law for Portugal and guided Lisbon’s new city plan. There were two other valuable initiatives that the prime minister added: he included the details about earthquake experience that had been collected and made them part of the overall plan for the city and added, in some detail, all that was known about the behavior of animals before and during earthquakes. Today we are well aware of the warning signals we get from all forms of life with regard to earthquakes but this was probably the first time they were given serious consideration.