But the ruins within and outside Rome awakened not only archæological zeal and patriotic enthusiasm, but an elegiac or sentimental melancholy. In Petrarch and Boccaccio we find touches of this feeling (pp. 177, 181). Poggio (p. 181) often visited the temple of Venus and Rome, in the belief that it was that of Castor and Pollux, where the senate used so often to meet, and would lose himself in memories of the great orators Crassus, Hortensius, Cicero. The language of Pius II., especially in describing Tivoli, has a thoroughly sentimental ring,[429] and soon afterwards (1467) appeared the first pictures of ruins, with, a commentary by Polifilo.[430] Ruins of mighty arches and colonnades, half hid in plane-trees, laurels, cypresses, and brushwood, figure in his pages. In the sacred legends it became the custom, we can hardly say how, to lay the scene of the birth of Christ in the ruins of a magnificent palace.[431] That artificial ruins became afterwards a necessity of landscape gardening, is only a practical consequence of this feeling. CHAPTER III. THE OLD AUTHORS. But the literary bequests of antiquity, Greek as well as Latin, were of far more importance than the architectural, and indeed than all the artistic remains which it had left. They were held in the most absolute sense to be the springs of all knowledge. The literary conditions of that age of great discoveries have been often set forth; no more can be here attempted than to point out a few less-known features of the picture.[432] Great as was the influence of the old writers on the Italian mind in the fourteenth century and before, yet that influence was due rather to the wide diffusion of what had long been known, than to the discovery of much that was new. The most popular Latin poets, historians, orators, and letter-writers, together with a number of Latin translations of single works of Aristotle, Plutarch, and a few other Greek authors, constituted the treasure from which a few favoured individuals in the time of Petrarch and Boccaccio drew their inspiration. The former, as is well known, owned and kept with religious care a Greek Homer, which he was unable to read. A complete Latin translation of the ‘Iliad’ and ‘Odyssey,’ though a very bad one, was made at Petrarch’s suggestion and with Boccaccio’s help by a Calabrian Greek, Leonzio Pilato.[433] But with the fifteenth century began the long list of new discoveries, the systematic creation of libraries by means of copies, and the rapid multiplication of translations from the Greek.[434]