III. What The Popes Have Done For Rome. 149 It is the residence of the Popes in Rome that has contributed to her material and religious grandeur. The Pontiffs have made her the Centre of Christendom, the Queen of religion, the Mistress of arts and sciences, the Depository of sacred learning. By their creative and conservative spirit they have saved the illustrious monuments of the past, and, side by side with these, they have raised up Christian temples which surpass those of Pagan antiquity. In looking today at these old Roman monuments we know not which to admire more — the genius of those who designed and erected them, or the fostering care of the Popes who have preserved from destruction the venerable ruins. The residence of the Popes in Rome has made her what she is truly called, "The Eternal City." Let the Popes leave Rome forever, and in five years grass will be growing on its streets. [148] Such was the case at the return of the Pope, in 1418, from Avignon, which had been the seat of the Sovereign Pontiffs during the preceding century. On the Pope's return the city of Rome had a population of only 17,000188 and Avignon, which, during the residence of the Popes in the fourteenth century contained a population of 100,000, has now a population of only 36,407 inhabitants. Such, also, was the case in the beginning of the present century, when Pius VII. was an exile for four years from Rome, and a prisoner of the first Napoleon, in Grenoble, Savona and Fontainebleau. Grass then grew on the streets of Rome, and the city lost one-half of its population. Rome has naturally no commercial attractions. It is only the presence of the Pope that keeps up her trade. Let the Popes abandon Rome, and her churches will soon be without worshipers; her artists without employment. Her glorious monuments will perish. Science and art and sacred literature will take their flight and perch upon some more favored spot. Memoir of Pope Sixtus V., by Baron Hilbner, Vol. II., ch. 1.