After the deaths of Petrarch and Boccaccio, the cause of learning was, to a certain degree, lost. The study of Greek and the search for manuscripts was discontinued. The first person who brought that language again into notice, was Emanuel Chrysoloras, a noble Greek, who was frequently sent into Italy on embassies by the emperor of Constantinople, and employed his leisure in teaching his native tongue in Florence. His disciples were numerous: among these. Poggio Bracciolini was the most distinguished. He discovered and collected a vast number of the most valuable manuscripts. Besides the philosophic and beautiful poem of Lucretius, we owe to him the complete copies of Quintilian, Plautus, Statius, Silius Italicus, Columella, and many others. Several of these exist only from the copy found by him, and were thus rescued from certain destruction. "I did not find them in libraries," he says, "which their dignity demanded, but in a dark and obscure dungeon at the bottom of a tower, in which they were leading the life of the damned." Filelfo was also an ardent collector. The discussions between the Roman and Greek churches brought several Greek scholars and philosophers into Italy, and through them the Platonic doctrines were known to the Italians. [Sidenote: 1438.] Gemisthus Pletho, who had been master of Chrysoloras, but who survived him many years, was their chief promulgator. They were in opposition to the Aristotelian philosophy, which had so long been the only one taught in the schools of Italy; but their glowing beauty and imagination were adapted to enchant all who heard them. Cosmo de' Medici became their convert, and resolved to establish an academy at Florence for their study and propagation. He caused Marsiglio Ficino, the son of his favourite physician, to be educated for this purpose by the teachers of Platonic philosophy. [Sidenote: 1453.] Cosmo was also the founder of the Medicean library. The taking of Constantinople by the Turks aided the advancement of learning; and while Cosmo protected many learned Greeks who took refuge at Florence, they spread refinement and knowledge throughout the peninsula. [Sidenote 1464.]