The Jews were the principal medium through which Moorish civilization was permanently impressed upon Europe. Their peculiar characteristics; their vitality amidst the most dreadful misfortunes; the intimate relationship maintained by their communities, where distance and territorial isolation seemed matters of little importance, and their wide distribution were most important factors in the maintenance and dissemination of knowledge. The Jew travelled with safety in lands where a price was set upon his head; outside of Moslem jurisdiction, even among strangers unfamiliar with his story and his creed, the Saracen was an outcast. The requirements of royal and ecclesiastical incompetency contributed to the preservation of that learning which ignorance and fear constantly incited to destroy. As the Peninsula yielded by degrees to the steady encroachments of Christian power, the superior abilities of the Jews proved a potent safeguard against oppression. In spite of the furious protests of fanatics, they exercised the most important public employments. Kings of irreproachable orthodoxy habitually availed themselves of their unrivalled medical attainments. The physicians of Alfonso X., Pedro el Cruel, Henry III., Juan II. of Castile, of Jaime I. of Aragon, of Duarte and Juan I. of Portugal, were all members of the detested sect. Their tact and discernment caused their services to be enlisted in the settlement of perplexing questions of diplomacy. The early times of the Reconquest were far from exhibiting the vindictive and intolerant spirit which marked its termination. The Hebrew colony at Toledo numbered twelve thousand souls. Its academy stood first in rank among similar institutions in Europe. A vast sum was annually paid by this tributary population into the royal treasury of Castile.