It is curious to observe, on the Pass of Antarangra, the partition of the waters flowing into the two great oceans, the Atlantic and the Pacific. Scarcely thirty paces distant from each other there are two small lagunas. That situated most to the west is one of the sources of the Rio de San Mateo, which, under the name of the Rimac, falls into the Pacific. The other laguna, that to the eastward, sends its waters through a succession of small mountain lakes into the Rio de Pachachaca, a small tributary to the mighty Amazon river. It is amusing to take a cup of water from the one laguna and pour it into the other. I could not resist indulging this whim; and in so doing I thought I might possibly have sent into the Pacific some drops of the water destined for the Atlantic. But the whim, puerile as it may be, nevertheless suggests serious reflections on the mighty power of nature, which has thrown up these stupendous mountains from the bosom of the earth; and also on the testaceous animals found on these heights, memorials of the time when the ocean flowed over their lofty summits.
From the ridge the road runs eastward along a branch of the principal mountain chain. This branch forms the southern boundary of a gently-sloping valley. The declivity is terrace-formed, and on each terrace there is a small clear lake. This series of lakes is called _Huascacocha_ (the chain of lakes). In their waters, as in most of the mountain rivers, there is found in great numbers a small species of shad-fish (_Pygidium dispar_, Tsch.). They are caught during the night in nets, or by lines, to which the bait is fastened by small cactus-thorns.
The third in the series of the lagunas is called _Morococha_ (the colored lake). On its banks some buildings have been constructed, for the smelting of copper ore. The mines which yield this metal are on the southern declivity, close to the road leading down from the Cordillera. Formerly these mines were worked for silver, but were not found very productive of that metal. Now they are again actively worked, and copper is obtained from them. The working of the Peruvian copper mines has hitherto been much neglected, though copper ore is exceedingly abundant.