VIA APPIA KOSE 



367 



i_ 1 £. f ^ a «• 5 4 >=- f r ^ f" .' 







ANCIENT ROMAN 2-LANE MILITARY ROAD. 



FRENCH ROAD (ROMAN METHOD) PREVIOUS TO 1775. 



TRESAGUET ROAD, FRANCE, 1775 TO 1830. 



ORIGINAL MACADAM ROAD. ENGLAND, 1816. 



MACADAM ROAD, UNITED STATES, 1900. 



HEAVY-DUTY 2-LANE CONCRETE PAVEMENT. UNITED STATES, 1934. 



FiGCEB 6. — Cross-sections comparing the thickness of road surfaces in ancient and modern 



times. 



