was not thinking of the Florida coast which he had visited on a former voyage, nor of the 'islands of India' discovered by Columbus, nor even of the Pearl Coast which he had followed after the Admiral in exploring. The expression occurs in his letter to Lorenzo de' Medici, written from Lisbon in March or April, 1503, relating solely to this third voyage. The letter begins as follows: 'I have formerly written to you at sufficient length about my return from those new countries which in the ships and at the expense and command of the most gracious King of Portugal we have sought and found. It is proper to call them a new world.' Observe that it is only the new countries visited on this third voyage, the countries from Cape San Roque southward, that Vespucius thinks it proper to call a new world, and here is his reason for so calling them: 'Since among our ancestors there was no knowledge of them, and to all who hear of the affair it is most novel. For it transcends the ideas of the ancients, since most of them say that beyond the equator to the south there is no continent, but only the sea which they called the Atlantic, and if any of them asserted the existence of a continent there, they found many reasons for refusing to consider it a habitable country. But this last voyage of mine has proved that this opinion of theirs was erroneous and in every way contrary to the facts." ... This expression 'Novus Mundus,' thus occurring in a private letter, had a remarkable career. Early in June, 1503, about the time when Americus was starting on his fourth voyage, Lorenzo died. By the beginning of 1504, a Latin version of the letter [translated by Giovanni Giocondo] was printed and published, with the title 'Mundus Novus.' ... The little four-leaved tract, 'Mundus Novus,' turned out to be the great literary success of the day. M. Harisse has described at least eleven Latin editions probably published in the course of 1504, and by 1506 not less than eight editions of German versions had been issued. Intense curiosity was aroused by this announcement of the existence of a populous land beyond the equator and unknown (could such a thing be possible) to the ancients,--who did know something, at least, about the eastern parts of the Asiatic continent which Columbus was supposed to have reached. The "Novus Mundus," so named, began soon to be represented on maps and globes, generally as a great island or quasi-continent lying on and below the equator. "Europe, Asia and Africa were the three parts of the earth [previously known], and so this opposite region, hitherto unknown, but mentioned by Mela and indicated by Ptolemy, was the Fourth Part. We can now begin to understand the intense and wildly absorbing interest with which people read the brief story of the third voyage of Vespucius, and we