Marco Polo, the Venetian, had traveled, as every one knows, across Asia to Cathay (China) in the thirteenth century and had visited the Great Khan or Emperor. On his return he wrote the "Relation," a most exaggerated but fascinating account of the wealth of that remote land and of Cipango (Japan) also, which the Chinese had told him about. The "Imago Mundi" was certainly better reading for him, because less exaggerated; whatever myths and fables it contained, it was not the sort of book to turn a young man's thoughts toward amassing wealth. Instead, its author had gathered together all that was known or seriously argued concerning this world. On this curious old volume Christopher pinned his entire faith. It became his bedside companion; and his copy of it, full of notes in his own handwriting and in that of his brother Bartholomew as well, may be seen to-day in the Columbian Library in Sevilla. For centuries it has been asserted by men who have written about Columbus that the most important event during his Lisbon days was his correspondence with a learned astronomer named Paolo Toscanelli. Columbus, they argue, having formed the plan of sailing west to discover a route to the Indies (which Columbus never thought of doing at that early day), wrote to ask Toscanelli's advice, and the wise Florentine approved most heartily. It appears from the astronomer's letter that he never dreamed, any more than did Columbus, that a whole continent lay far off in the unexplored western ocean. He supposed the world to be much smaller than it really is, with the ocean occupying only a seventh of it; and that if one sailed three or four thousand miles west, he would surely come to the islands of Cipango (pronounced in Italian Tchi- pango), or Japan, lying off the mainland of Cathay or China. Toscanelli, like Columbus, had read all about the Far East in Marco Polo's book, and was convinced that if the Venetian had reached it by going east overland, some one else might reach it by going west oversea. Accordingly he encouraged the aspiring young explorer. He told Columbus, furthermore, that he had talked with an ambassador from the Far East who came to the court of Pope Eugenius IV. "I was often in the Ambassador's company," he wrote, "and he told me of the immense rivers in his country, and of two hundred cities with marble bridges upon the banks of a single river." Of Cipango he wrote, "This island contains such an abundance of precious stones and metals that the temples and royal palaces are covered with plates of gold!"