Marco was introduced to the khan by Nicolo, as "your majesty's servant and my son"; but had he been a son of the ruler himself he could not have received greater honors than were bestowed upon him by the emperor. Having a natural aptitude for acquiring languages, he soon could read and write four different dialects, and being possessed of great intelligence and shrewdness withal, he was sent by the khan on important missions to various parts of his kingdom. He acquitted himself so well on these embassies, some of which required his absence from the capital for many months, and he brought back such interesting accounts of the people he met and their customs, that he was constantly employed. In this manner he acquired, during many years of service in high positions, a most intimate acquaintance with the khan's dominions, and became immensely rich. His father and uncle shared wealth and honors with him, for they likewise were congenially employed; but the time came at last when their desire to revisit Venice became too strong to resist. They craved the khan's permission to depart; but when the old monarch heard their request he flew into a passion, declaring that he would never allow them to go. They should remain with him and become the richest men in the world. Marco was sent off on another mission, this time by sea, and, discovering that there was direct communication between Cathay and the Indies, he entreated the khan to allow the Polos to go on a voyage, promising faithfully that they would return after a short stay with their friends in Venice. The old khan gave his consent reluctantly, overwhelming them with gifts at their departure, among other things giving them a tablet of gold, on which were engraved his orders to all the subjects in his vast dominions to provide guides, escorts, pilots--every convenience for their voyage and journey--without cost. He also authorized them to serve as his ambassadors to the pope and other European potentates, presented them with many precious stones, including rubies of great value, and money enough to defray their expenses for at least two years. From all this it will be seen that the grand khan was a very munificent prince, whose deeds must have made a lasting impression upon the minds of the generation in which he lived.