CHAUCER'S first glimpse of the idea of great poetry was derived, as we have seen, from the work of Froissart, De Machaut, and the authors of Le Roman de la Rose. In middle life that idea was enlarged when his visits to Italy, first in 1373 and again in 1378, introduced him to the work of Dante, Petrarch and Boccaccio. The mysticism of Dante made little or no appeal to Chaucer's practical mind, though he imitated the invocation to the Virgin from Paradiso xxxiii in the prologue to his Life of St. Cecilia. He attempted Dante's terza rima in A Complainte to his Lady (ll. 15-40) but seemingly made no further practice in this difficult metre; and it would appear that he parodied or at least was influenced by the triple form of the Divina Commedia in his House of Fame. But though Chaucer was familiar with Dante's great poem, he was unfitted by temperament to appreciate it to the full. Perhaps its greatest influence upon Chaucer was that it sent him back to Virgil to rediscover in the Æneid the romance of Troy and the tragic story of Dido's love which he celebrated in The House of Fame and in The Legend of Good Women. Petrarch too made little impression on Chaucer. That he was familiar with some of the Canzoniere is apparent from his translation of the sonnet beginning "S'amor non è, ch'è dunque quel ch'i'sento? " in Troilus and Criseyde, i, ll. 400-420; and it is not impossible that he had read the Trionfi; if, as has been suggested Petrarch's Trionfo della Fama influenced The House of Fame, with its famous names graven on the rock of ice, like the great ones of the Trionfo del Tempo.