The greatest, however, of all the conceptions of Pope Nicholas, the very centre of his great plan, was the library of the Vatican, which he began to build and to which he left all the collections of his life. Vespasian gives us a list of the principal among these five thousand volumes, the things which he prized most, which the Pope bequeathed to the Church and to Rome. These cherished rolls of parchment, many of them translations made under his own eyes, were enclosed in elaborate bindings ornamented with gold and silver. We are not, however, informed whether any of the great treasures of the Vatican library came from his hands--the good Vespasian taking more interest in the work of his scribes than in codexes. He tells us of five hundred scudi given to Lorenzo Valle with a pretty speech that the price was below his merits, but that eventually he should have more liberal pay; of fifteen hundred scudi given to Guerroni for a translation of the _Iliad_, and so forth. It is like a bookseller of the present day vaunting his new editions to a collector in search of the earliest known. But Pope Nicholas, like most other patrons of his time, knew no Greek, nor probably ever expected that it would become a usual subject of study, so that his translations were precious to him, the chief way of making his treasures of any practical use. The greater part, alas! of all his splendor has passed away. One pure and perfect glory, the little Chapel of San Lorenzo, painted by the tender hand of Fra Angelico, remains unharmed, the only work of that grand painter to be found in Rome. If one could have chosen a monument for the good Pope, the patron and friend of art in every form, there could not have been a better than this. Fra Angelico seems to have been brought to Rome by Pope Eugenius, but it was under Nicholas, in two or three years of gentle labor, that the work was done. It is, however, impossible to enumerate all the undertakings of Pope Nicholas. He did something to reestablish or decorate almost all the great basilicas. It is feared--but here our later historians speak with bated breath, not liking to bring such an accusation against the kind Pope, who loved men of letters--that the destruction of St. Peter's, afterward ruthlessly carried out by succeeding popes, was in his plan, on the pretext, so constantly employed, and possibly believed in, of the instability of the ancient building. But there is no absolute certainty of evidence, and at all events he might have repented, for he certainly did not do that deed. He began the tribune, however, in the ancient church, which may have been a preparation for the entire renewal of the edifice; and he did much toward the decoration of another round church, that of the Madonna delle Febbre, an ill-omened name, attached to the Vatican. He also built the Belvedere in the gardens, and surrounded the whole with strong walls and towers (round), one of which, according to Nibby, still remained fifty years