Tradition recounts that the Incas had migrated to Cuzco from unknown ancestral seats--by some conjectured to have been the shores of the prehistoric fresh-water sea of the Amazon plain--under the leadership of Manco Capac, the first of an unbroken line of sovereigns who claimed descent from the Sun-god and ruled the Incas until the Spanish conquest. The Incas developed a religion whose elaborate and rigid ritual, which regulated every act of their lives, finds its best parallel among the Hebrews. Each family had its household god; each sept worshipped an imaginary ancestor; the whole nation adored the sun as the progenitor of the reigning family, and the monarch's person was revered as divine. So profound was the religious feeling of this people that they finally rose to the conception of a supreme deity--a creator of the universe. His temple filled one side of the great square at Cuzco. Even more remarkable than their religious system was the social and industrial organisation of the Incas. Private property in land did not exist. It belonged to the septs and was from time to time allotted to the heads of families. Every person was obliged to work, all males being divided into classes according to age and strength, and suitable labour assigned to each. The produce, whether crops or livestock, was divided between the government, the priesthood, and the communes. Scarcity in one section was made up from the plenty in others; public officers annually revised the allotments, and turns at the irrigation works were taken in accordance with fixed rules. Not a spot of cultivable land was left unused. Habitations were built on rocky hills; deserts or the sides of barren cliffs were used for cemeteries; whole mountain sides were terraced up thousands of feet, and land was literally created by years of patient labour employed in bringing earth in baskets and laying it on the bare rocks. By no people has irrigation been more extensively and successfully applied, and in spite of their ignorance of iron and steam, of labour-saving appliances and instruments of precision, the Incas constructed a system which in real effectiveness has never been surpassed. Many of their canals, reservoirs, and terraces were allowed to crumble by the Spanish conquerors, but modern Peru still lives upon the half-ruined fragments of the mighty works of the Incas.