This information is as accurate and authentic as any which a long line of distinguished explorers and archeologists have been able to substitute for it. Men of sane judgment agree in admitting that there is nothing to justify any conclusion. But they also agree that the significance of Tiahuanacu exceeds everything hitherto discovered in Peru. It recalls Carnac and Philae. It stands with the dolmens of Brittany, Stonehenge, and the cyclopean terraces of the South Sea Islands, as a great riddle of human history. [Illustration: A GOD OF TIAHUANACU.] II Dropped in the bottom of yawning red gulfs, with snow-peaks glistening overhead, are wild valleys of differing climates, the mighty _quebradas_ of the Andes. These canyons, which the famous hanging bridges used to span, intersect the wilderness. They lie in dusk while the over-arching cliffs are bathed in full sunlight, for sunrise and sunset are within a few hours of each other. The warm air, steaming upward, pushes the snow boundary far above. Strata of black sand on the valley’s walls have been tunneled by cave-dwellers of ancient times. French sisters of charity move about in cloisters under eucalyptus trees. Such a surprise is Yucay, tucked in snugly between two mountains, wrapped in soft air and scents of unknown flowers, the loveliest spot in all the empire of the Incas. Streams of clear water descend to it from above and form the smooth, deep river of Yucay. The Incas sought it out for their gardens of pleasure and were lulled to rest by bells of gold tied to the hammocks in which they slept. Water has a very tranquillizing effect. It sweeps along a valley, and the jagged remnants of volcanic action are smoothed out into long undulating lines. Water collects in all crevices; lakes green as iron vitriol, fed by subterranean springs, lie in the surly country like jewels in their setting. When night shadows have settled in the valleys, the alpine glow is reflected in the quiet surface. There are no fish in the lake of Chinchaycocha, Laguna de Reyes. Though their element is water and they die in air, here they die in pure water for lack of air. The _ingahuallpa_ sings a monotonous note from the bank at the close of every hour during the night. The outlet of the lake is narrow and deep, and its clear water flows smoothly and without noise.