"Are you then sure, the power which would create

The universe and fix the laws of fate,

Could not have found for man a proper place,

But earthquakes must destroy the human race?"

"Lisbon Earthquake Poem" (1755) by Voltaire

November 1, 1755 was to be a sunny autumn day in the city of Lisbon, one of the most important and richest seaports of Europe at the time. The locals were profoundly religious and the city was preparing to celebrate the day of All Saints, with the obligatory criminal proceedings of heretics in the afternoon.

At 9:30 in the morning the inhabitants were alarmed by weak tremors. Christian Staqueler, consul of the German city of Hamburg, remembers in a later report: "First we heard a rumble, like the noise of a carriage, it became louder and louder, until it was as loud as the loudest noise of a gun, immediately after that we felt the first tremble."

At 9:40 all the bells of the city began to ring simultaneously and only seconds later the first buildings collapsed. Three major shakes followed in the next 10 minutes, most people were killed by the collapse of the churches, full of believers attending the second mass of the day,

People fled in the direction of the seaport where the large squares of the royal palace promised shelter from the debris of the collapsing buildings. It was there that they witnessed a strange phenomenon: The sea had vanished and the riverbed of the Tejo was dry. At 10:10 a 12 meter high tsunami-wave reached the city and destroyed the entire harbour, thousands of people standing along the shores were swept away and killed.

After the earthquake and the tsunami a terrible fire broke out; raging for five days it destroyed what earth and water had left over.

In the end three quarters of the city lay in ruins, estimated 30.000 - 60.000 people killed, the earthquake further damaged cities on the coast of Morocco, the tsunami caused havoc in Ireland and the African coast and waves of 4 meters reached the Caribbean islands.

Fig.1. Lisbon, Portugal, during the great earthquake of November 1, 1755. This copper engraving, made in the same year, shows the city in ruins and in flames. Tsunamis rush upon the shore, destroying buildings and killing people, even the ships anchored in the harbour sunk (image in public domain).

After the earthquake for the first time in history a sort of crisis management was organized, king Joseph I commissioned the peer and permanent secretary Sebastian Jose Carvalho e Melo (1699-1782, rewarded later by the king and declared Marques de Pombal) to supervise the rescue of the injured, the disposal of the corpses and the reconstruction of the city.

The earthquake had wide-ranging effects on the society and culture in Europe. The earthquake had struck on an important religious feast and had destroyed almost every important church in a devoted Roman Catholic city. Theologians and the religious authorities - like the Jesuit Malagrida in Lisbon - exploited the situation and the superstitiousness of the people, declaring that the earthquake was a punishment by god for the sins of the world - but why then should god destroy the churches and spare the brothels? (The churches were mostly located in the city center and build on soft sediments deposited by the Tejo. Such sediments are prone to soil liquefaction during an earthquake, destabilizing the fundaments of large buildings).

Philosophers, naturalists and even some theologians had argued already since ancient times against this simple view of the world and proposed naturalistic explanations of volcanoes, earthquakes and other natural disasters: the most common hypotheses comprised air circulation in the crust of the earth, tremors as the results of electric discharge or the spontaneous explosion of gases in the underground.

But until the earthquake of Lisbon such ideas were hold mostly by a small number of scholars and discussed in restricted circles. With the possibility to produce cheap and fast pamphlets and journals the news of the destruction of such an important city as Lisbon became widely known and discussed in Europe.

The earthquake, the many figures produced over the years and the subsequent discussions had shaken profoundly the belief in a merciful god and the power of the church - for the first time an earthquake was regarded widely as a natural phenomena.

Bibliography:

KÖLBL-EBERT, M. (2005): Lissabon 1755 - Anatomie einer Erderschütterung. Archaeopteryx - Jahreszeitschrift der Freunde des Jura-Museums Eichstätt 23: 83-98

KOZAK, J. & CERMAK, V. (2010): The Illustrated History of Natural Disasters. Springer-Verlag: 203

UDIAS, A. (2009): Earthquakes as God's punishment in 17th- and 18th-century Spain. In KÖLBL-EBERT, M. (ed.) Geology and Religion: A History of Harmony and Hostility. The Geological Society, London, Special Publications, 310: 41-48

WALKER, B. (1982): Earthquake - Planet Earth. Time Life Books: 154