The year of their return to Venice, 1269, is agreed upon on all hands; and as Marco was born in the first year of their absence, he would then be about nine years of age. Ramusio, who dates the commencement of the first journey in 1250, supposes Marco to have been fifteen years of age at the return of his father and uncle, which is absurd; as, if the era assumed by Ramusio were possibly true, he must then have been in his nineteenth year. According to the opinion of Mr J. R. Forster, the commencement of the second journey in which Marco was engaged, must have been in 1271; and he founds this opinion on the circumstance, that Gregory IX. had then been elected pope, from whom they carried letters for Kublai-khan. But it will appear from the travels themselves, that the three Polos had commenced their journey previously to the election of that sovereign pontiff, and that they were detained some time in Armenia, in consequence of an express sent after them for the purpose, that they might there wait for his final instructions. They may, therefore, have commenced this second journey in 1270. We only know, however, that they set out from Venice for a second journey into Tartary, soon after their return from the first, in 1269; and that they carried young Marco along with them. On his appearance at the court of Cambalu, Kublai-khan took a fancy to the young Venetian, and caused him to be instructed in four of the principal languages which were spoken in the extensive dominions of the Mongals. Marco was afterwards employed by the khan, for a considerable number of years, in several important affairs, as will appear in the relation of his travels. At length, the three Polos returned to Venice, in 1295, after an absence of twenty-five or twenty-six years, during which long period they had never been heard of by their friends and countrymen, seventeen years of which Marco had been employed in the service of the great khan. On their return to their own house in Venice, they were entirely forgotten by their relations and former acquaintances, and had considerable difficulty to establish their identity, and to get themselves recognized by their family, and were obliged to use extraordinary means to recover the respect which was their due, and an acknowledgement of their name, family, and rank, the particulars of which will be found in the travels themselves. About three years after the return of these adventurous travellers, hostilities arose between the republics of Genoa and Venice. The Genoese admiral, Lampa Doria, came to the island of Curzola with a fleet of seventy gallies, to oppose whom, the Venetians fitted out a great naval force under Andrea Dandolo, under whom Marco Polo had the command of a galley. The Venetians were totally defeated in a great naval engagement, with the loss of their admiral and eighty-five ships, and Marco Polo had the misfortune to be among the number of the prisoners.