Had it not been for the enthusiasm of a few collectors of that age, who shrank from no effort or privation in their researches, we should certainly possess only a small part of the literature, especially that of the Greeks, which is now in our hands. Pope Nicholas V., when only a simple monk, ran deeply into debt through buying manuscripts or having them copied. Even then he made no secret of his passion for the two great interests of the Renaissance, books and buildings.[435] As Pope he kept his word. Copyists wrote and spies searched for him through half the world. Perotto received 500 ducats for the Latin translation of Polybius; Guarino, 1,000 gold florins for that of Strabo, and he would have been paid 500 more but for the death of the Pope. Filelfo was to have received 10,000 gold florins for a metrical translation of Homer, and was only prevented by the Pope’s death from coming from Milan to Rome. Nicholas left a collection of 5,000, or, according to another way of calculating, of 9,000 volumes,[436] for the use of the members of the Curia, which became the foundation of the library of the Vatican. It was to be preserved in the palace itself, as its noblest ornament, like the library of Ptolemy Philadelphus at Alexandria. When the plague (1450) drove him and his court to Fabriano, whence then, as now, the best paper was procured, he took his translators and compilers with him, that he might run no risk of losing them. The Florentine Niccolò Niccoli,[437] a member of that accomplished circle of friends which surrounded the elder Cosimo de Medici, spent his whole fortune in buying books. At last, when his money was all gone, the Medici put their purse at his disposal for any sum which his purpose might require. We owe to him the completion of Ammianus Marcellinus, of the ‘De Oratore’ of Cicero, the text of Lucretius which still has most authority, and other works; he persuaded Cosimo to buy the best manuscript of Pliny from a monastery at Lübeck. With noble confidence he lent his books to those who asked for them, allowed all comers to study them in his own house, and was ready to converse with the students on what they had read. His collection of 800 volumes, valued at 6,000 gold florins, passed after his death, through Cosimo’s intervention, to the monastery of San Marco, on the condition that it should be accessible to the public, and is now one of the jewels of the Laurentian library.