I have described the great estuary formed by the junction of this immense volume of fresh water with the sea, and I believe this to be the result of the union of a number of rivers coming together in the form of a lake, rather than a river, as is claimed. I also think the fresh water rushes down from very high mountains, and pours into the salt waters beneath, with such violence that the sea-water cannot penetrate unto the bay. Doubtless there will be found people who will express astonishment at my imagination, and throw ridicule on me, saying, "Why does he repeat this, as though it were a miracle? Has not Italy the Po, which illustrious writers have named the king of rivers? Are not other regions watered by great rivers, such as the Don, the Ganges, the Danube, whose waters drive back those of the sea with such force that fresh, potable water is still found forty miles from their mouths?" I would answer their objections as follows: in the Alpine chain rising behind the Po and separating Italy from France, Germany, and Austria, water never fails. The long valley of the Po also receives the waters of the Ticino and many other streams flowing towards the Adriatic; and the same may be said of the other rivers mentioned. But these rivers of the new continent, as the caciques informed the Spaniards, flow through greater and shorter channels into the ocean. Some people believe that the continent is very narrow in this part, and that it spreads; out considerably in other places. Another argument, which I hold to be a poor one, I must nevertheless mention. This continent is narrow, but its length extends for an immense distance from the east to the west. Just as is recounted of the river Alpheus of Elide, which disappears in channels under the sea to reappear in Sicily at the fountain of Arethusa, so there may exist in the mountains of this continent a vast network of subterranean passages in such wise that the waters produced by the rains we have mentioned may be collected. Those who explain phenomena by common sense, and those who enjoy criticism may choose the theory which best pleases them. For the moment there is nothing more I can add on this subject. When we shall learn more, we shall faithfully relate it. We have already dwelt sufficiently upon the width of this continent, and it is now time to consider its form and length.