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Show THE ROMANS KNEW HOW Some of the highways built by the Romans 2.000 years ago are still in active use. These highways have lasted through the centuries simply because of their construction. An earth subgrade. .carefully prepared pre-pared and drained, was the foundation founda-tion for four layers of material, each so carefully laid that it contributed greatly to the long life of the road. First came the statumen, or found ation, then the rodus, next the nucleus, nu-cleus, and finally" the pavement or wearing surface. The statumen and pavimentum consisted of large flat stones, while the two intervening courses were built of smaller stones laid in lime mortar. For the chariot and pack horse traffic of Roman times such pavements pave-ments seem ridiculously heavy but the wisdom of the builders was amply am-ply demonstrated by S00 years during dur-ing which the Roman road system formed the backbone of the transportation trans-portation system of the ancient empire. |