Who now can manufacture transparent gold, malleable glass, and quenchless lamps; construct garden Ships, and self-directing magnetic chariots, build hanging gardens, or elevated Viaducts and aqueducts of Cyclopean proportion, such as are found in the ruins Of Central and South America A recent explorer remarks: The Incas tempered copper to an edge keen as steel; they cut jewels with an art that modern lapidaries cannot imitate their colours are as lasting as their architecture; under their political economy millions Of people lived as one family.