Shipping Roman grain across the Mediterranean beat carting it 15 miles
By one estimate, a Roman merchant ship could carry grain the full length of the Mediterranean for less than it cost to haul the same load 15 miles by road. That arithmetic fed the capital: over the first three centuries AD, Rome ate roughly 150,000 tons of Egyptian grain a year, nearly all of it delivered under sail.
Until land transport improved in the 19th century, going by water, where possible, was quicker, cheaper and safer than any overland route. London's coal came the same way. Colliers had been bringing it down the coast from mines near the River Tyne since at least the 14th century, and in 1795 some 4,395 cargoes arrived, work for about 500 ships making eight or nine trips a year. The trade doubled by 1839, the first steam collier was launched only in 1852, and sailing colliers kept working into the 20th century.
Sailing seems to have been invented more than once. Island Southeast Asia and the Mediterranean world are the two likeliest birthplaces, and Ecuador's Guayaquil River, where current and wind run in opposite directions just as on the Nile, may be a third. The Caribbean, despite warm water and islands within sight of each other, never developed sail and adopted it only after Europeans came. On the Nile a boat could ride the current 750 miles north and sail home. The first picture of a sail, from Egypt, dates to about 3100 BCE, though a Mesopotamian pot from the 6th millennium BCE may show a two-legged mast on a reed boat.
Austronesian voyagers explored cleverly: their boats could sail into the wind, so they headed upwind in search of land, knowing a downwind run would bring them home if they found nothing. Stick charts helped them navigate open ocean.
Speed peaked with the clippers of the early 1800s, whose masts rose to 100 feet and which could manage 19 knots and cover up to 465 nautical miles in a day. Iron-hulled sailers built from the 1870s to 1900 still outran early steamers that barely made 8 knots, but the Suez and Panama canals, which suited steam, finally made sail uneconomic.
Source: Sailing
