The Giralda is the greatest of all the monuments of that enlightened civilization. She is so different from any other tower that comparison becomes difficult. There is a robustness, an appearance of adequate solidity and strength which are lacking in the Italian towers of Saint Mark's, of Pistoja, or of Florence. This holds true even in relation to other Moorish towers, or such edifices as the Mosque at Cordova, the Alcazar at Seville, or the pillared halls of Granada; all other Moorish work seems to have a certain feminine weakness, a timidity and insecurity, when compared with the tower which dominates Maria Santissima. The Giralda is your first and last impression of this corner of the world, for it embodies all the grace and strength that can be combined in architecture. Old Spanish authorities assert that it was in the very year when believers throughout Christendom were anxiously expecting the end of the world that the Moslem infidels began to build their huge monument. More probably it was started about the year 1185, as the prayer tower or minaret of the mosque which was then rapidly progressing. The Spanish historian Gayangos says that it was completed by Jabar or Gever in 1196, during the reign of the illustrious Almohad ruler, Abu Jakub Jusef, the same monarch who erected the Mesquita at Cordova. Other authorities insist that its original purpose was as an observatory,--but although it may have been used for astronomical purposes, it was certainly erected as a tower from which the muezzin could call the faithful to prayer in the Mosque of Seville. While building it, Gever claims to have invented algebra. The original tower has undergone skillful but of course detrimental changes from the hands of later generations. We have descriptions and representations of it prior to the changes made in 1500. The main Arab structure was, like almost all Mohammedan prayer-towers, surmounted by a smaller tower and capped by a spire. It was about 250 feet high, and on its summit an iron standard supported, before the earthquake of 1395, four enormous balls of brass. King Alfonso the Wise, in his "Cronica de España," describing Seville in the thirteenth century, says that "when the sun shone upon these balls, they emitted so fierce a light that they might be seen a day's journey away from the city." When Seville was taken by Saint Ferdinand in 1248, the tower was standing in the full glory of its original conception. The thought that it might fall into the hands of the conquerors so horrified its builders that they were only prevented from destroying it by Saint Ferdinand's threat that, if a single brick were removed, not an infidel in Seville should keep his head.