The designation pozzolana is derived from one of the primary deposits of volcanic ash used by the Romans in Italy, at Pozzuoli. Nowadays the definition of pozzolana encompasses any volcanic material (pumice or volcanic ash), predominantly composed of fine volcanic glass, that is used as a pozzolan.
The Fourth Crusade and the crusading movement generally thus resulted, ultimately, in the victory of Islam, a result which was of course the exact opposite of its original intention. The Fourth Crusade is depicted in Poul Anderson 's novel There Will Be Time from the point of view of a 20th Century Time traveler who saves the life of a Byzantine girl during the carnage and falls in love with her.
The Crusades happened when they did, because the Muslims had taken the holy city of Jerusalem in the seventh century.This was deeply troubling, but the Christian kings and lords could do nothing about it at the time.he third crusade happen in Jerusemalum in 1984       i've always believed that the third crusade happened in medieval times in/at jerusalem. the crusade was a â¦ plan to recapture the Holy lands from the Turks/Muslims. Which it did. 4 people found this useful.