COATI ISLAND AND THE RUINS OF TIAHUANACO.--RETURN TO PUNO.--CUZCO, AND THE TEMPLES, PALACES, AND FORTRESSES OF THE INCAS.--PLANS FOR DEPARTURE. [Illustration: BRIDGE AND CUSTOM-HOUSE AT THE FRONTIER.] The party spent the day on Titicaca Island, examining the ruins which attested the power of the Incas and their predecessors, and studying the magnificent views that were presented in almost every direction. In the east lay the Andes of Bolivia, while to the west was the chain of the cordillera they had crossed on their way from the coast to Puno. Lake Titicaca lies between Peru and Bolivia, the western shore belonging to the former country, and the eastern to the latter. The outlet of the lake is the dividing-line, and at each end of the bridge which crosses the river there is a custom-house, where officials of the respective countries are stationed. The bridge is built on rafts, or balsas, made of the reeds growing in the lake; the footway is composed of these reeds, and supported by the balsas beneath it. They returned to the steamboat at nightfall, and gave orders for the captain to move to Coati Island, about six miles distant, as soon as daylight permitted. Weary with their tramp, they slept soundly; when they waked in the morning the steamer was at anchor at its destination, and as soon as breakfast was over they went on shore. Titicaca Island was specially consecrated to the sun, while Coati was dedicated to the moon. The former is steep and rugged; the latter is only moderately elevated, and capable of cultivation from one end to the other. It is about half as large as Titicaca Island, and is occupied by a few families of Indians, who cultivate potatoes and other things, and look after a flock of sheep which is pastured there. Judging by the appearance of the sheep, Frank and Fred were of opinion that the pasture was a good one. [Illustration: RUINS ON COATI ISLAND.] Coati contains a Temple of the Moon and a Palace of the Virgins; both are greatly ruined, but sufficiently preserved to indicate their original extent and character. Near the ancient landing-place there are gates, and temples of purification similar to those on Titicaca Island, and doubtless used for the same purposes. About midway of the island is the principal group of ruins, and our friends spent several hours in examining the walls and terraces, and studying what is left of the architecture of the buildings. Only the lower story of the edifice remains; the upper part appears to have been made of wood, and disappeared long ago.