Probably the most advanced tribes lived along the Pacific border. In Colombia, Ecuador, Peru, Bolivia, and Chili many relics of ancient art and many ruins of old buildings are found. Here and there east of the mountains similar evidences of culture are found, but they are less known. Best known of all are those of Peru. The ancient Indians of Peru were industrious and hard workers. Their rulers, the Incas, were called “the children of the sun.” The old Peruvians had important towns and cities. They diligently cultivated their fields and irrigated them by great systems of canals. They wove capital cotton cloth, from which they made good clothing. Their cloth was often decorated with pretty inwoven designs in colored threads. They tamed and bred the llama, and trained it for a pack animal. They could not write, but kept accounts by knotted cords called _quipus_. Differently colored cords were used for different things, and knots of varying sizes stood for varying numbers. Thus an owner of llamas might use a white cord for males, a reddish cord for females, and a yellow cord for young. A simple knot might stand for _one_, and larger knots might mean _five_, _ten_, or _twenty_. In this way the herder might keep exact account of his animals. [Illustration: PERUVIAN ANTIQUITIES (RATZEL).] The old Peruvians were great potters and thousands of their old water vessels and food dishes, which were buried with the dead, have been dug up. These had curious forms and were often adorned with colored patterns. Some of these jars were shaped like human faces, human figures, or animals. Sometimes they were “whistling jars,” which were so made that they whistled when water was poured in or out of them. The old Peruvians were skilled in working copper, silver, and gold, and made many ornaments and figures in these metals. They disposed of their dead carefully, and many of the dried bodies, or “mummies” have been found in the ancient graves. The dead were folded into a sitting position and bound; they were then wrapped about with fine cloths. After the last wrapping was in place, it was painted, a false face was marked on the cloth or placed over the proper place, and imitation ear ornaments were hung at the sides of the head. Many objects were buried with the dead,—vessels of food and drink, and the objects they had used in life,—with a woman, cotton, spindle, and work-basket; with a man, weapons and ornaments. The old Peruvians built fine public buildings, and temples of stone and some ruins of such buildings still remain.