All this caused incredible fatigue to the men, unaccustomed to such service, and supported only on the dry and salt provisions they had with them. Their legs became swelled with working for days together in the water, and they were covered with sores from the bites of the flies and mosquitos which hovered in clouds above its surface. The scurvy broke out, and some of them became seriously ill: fortunately they fell in with some apple-trees, the fruit of which was a great comfort to the sick; but the snow-capped peak of the Cerro Imperial, as well as the whole range of the Cordillera, was now in full view before them; and the hope of being soon in communication with Valdivia gave them fresh courage, and redoubled their exertions to reach their journey's end.
Two whole months were spent in making a distance of forty-one leagues from the Neuquen. This brought them, on the 25th of March, to the foot of the great range of the Cordillera, and to an island about a mile and a half long, where the main stream was found to be formed by two distinct rivers, there uniting from opposite directions; the one coming from the south, the other from the north.
As they knew by their latitude, which a little before reaching this point they had found to be 40° 2´ S., that they were already to the south of Valdivia, Villariño had no hesitation as to which of these rivers he should attempt to ascend. Before going on, however, he determined on giving the men a day or two's rest, of which he availed himself to make a short excursion in his little boat up the southern fork, which turned out to be a river of some magnitude.
At its mouth, he says, even at that time, when the waters were at their lowest, it was about 200 yards across, and about five feet in depth; its course from the S.S.W., running with much velocity through a deeply-cut channel over a bed of large rounded stones: the country, as far as could be seen, was a desolate mass of gravel. Some little way up, they found the burial-place of an Indian cacique, over which two stuffed horses were stuck upon stakes, according to their custom; further on, the shore was strewed with trunks of many large trees brought down by the floods; they were of various sorts, but principally pine and cedar, probably the same as is shipped in large quantities from the opposite side of the Cordillera, and from Chiloe, for other parts of Chile and Peru. From the Indians they subsequently learned that dense forests of these trees were to be met with higher up the river. How valuable they would be to the settlers on the Rio Negro, and how easily they might be floated down to them!