Of all earthquakes perhaps the best known and remembered is that of Lisbon on November 1st, 1755, and volumes have been written about it. The first shocks of this earthquake came without other warning than a deep sound resembling thunder, which appeared to proceed from beneath the ground, and it was immediately followed by a quaking which threw down the entire city of Lisbon. In six minutes sixty thousand persons perished. The day was almost immediately turned into night, owing to the thickness of the dust from the ruined city. A few minutes afterwards fire sprang up among the ruins. The new Lisbon quay, which had been built entirely of marble, suddenly sank down into the bay with an immense crowd of people, who thronged to it for safety, and it is said that none of the bodies of the drowned were ever seen again. Following hard on the first shocks the sea retired from the land, carrying boats and other craft with it, only to return in a great wave, which completed the destruction in and about the city. This great sea wave, the mightiest that has ever been described in connection with an earthquake, is said to have washed not only the coasts of Portugal and Spain, but to have extended with destructive violence to other countries. At Kinsale, in Ireland, it was strong enough to whirl vessels about in the harbour and to pour into the market-place, and it was of great violence also at the island of Madeira. Portions of the sea-coast between Cape-da-Roca and Cape Carvociro fell away into the sea, and the damage was very great along the coast between Cape St. Vincent and the mouth of the Guadiana. The great Sierra da Estrella, on the west of the Tagus valley, was split and rent in a most remarkable manner, and threw down avalanches of rock into the valley.