• Choose a category
• All
• Classic-Fiction

By Root 2883 0

Middle Ages, to improve laborsaving machinery and develop alternative sources of power to human muscles. Some of the medieval inventions were very simple, though important, like the wheelbarrow. The Romans had been extraordinarily slow in making effective use of the horse, making do with a type of ox yoke or a harness consisting chiefly of a breast band. In contrast, by the twelfth century, medieval farmers had developed shafts, little used by the Romans, and traces, and they transformed the inefficient breast band into the stiff, padded horse collar, thereby multiplying the tractive power of the horse fivefold. To support the medieval knight, with his heavy armor, the French bred ever-stronger horses, which developed into the modern carthorse. These powerful animals, substituted for oxen at the plow, more than doubled agricultural productivity, and made it possible for farmers to substitute all-iron for wooden plows, thus raising it further. Such horses also pulled bigger carts, equipped with a swiveling front axle and more efficient concave wheels. In fourteenth-century England, cartage costs, when the return journey could be made in a day, fell to a penny per ton per mile, and more and more bridges made land travel, for the first time, competitive with water transport.

The Romans knew about the water-powered mill, and they made some large specimens. But they were slow to build mills, preferring slaves, donkeys and horses to supply power; Vespasian, emperor A.D. 69–79, was even said to have opposed the extension of waterpower because it would throw men out of work. Shortage of iron also made the Romans reluctant to replace inefficient wooden gearing. In the Middle Ages, iron production increased steadily, making it cheaper and available for a variety of purposes, including gearing. Medieval forges also produced, for the first time, cast iron, invaluable for harnessing power of all kinds. So thousands more water mills were built. In England, south of the Trent, the Domesday Book lists 5,624 water mills. Gradually, water-powered mills were used for sawing timber, fulling, ore crushing, metal hammering and mining. Their ubiquity and importance are reflected in complex laws governing the control of rivers. Moreover, from the twelfth century, waterpower was joined by wind power as a means of turning heavily geared metal-grinding machinery. Windmills, unknown to the Romans, were built in large numbers and often of prodigious size. There were eight thousand in the Netherlands alone, where they were used not only for grinding corn but for pumping water, thus making possible drainage schemes that expanded the cultivable land area, a process taking place in many parts of Europe.

The complex sail power used in the powering of windmills and the development of sail power for ships were connected, and helped to explain why medieval mariners were able to improve so markedly on Roman sea transport, largely confined to the oar-propelled galley. The cog, driven entirely by sail, made its appearance in the thirteenth century, chiefly in the northern waters of the Hanseatic League. It was succeeded in the fourteenth century by the Portuguese caravels, lateen-rigged ships with two or three masts, multiple decks and a big hull—in all essentials modern sailing ships—often weighing six hundred tons or more and carrying their own weight in cargo. Such vessels were capable of sailing into and across Atlantic seas, and eventually did so, aided by the invention of the magnetic compass, mechanical timepieces and navigational charts, which were improving all the time.

With revolutionized sea power and improved land transport, internal and external trade in Europe virtually doubled with each generation. Overseas trade, especially with the East, made plague more common, and outbreaks such as the Black Death (1347–51) decimated the population. But there is no evidence that plague interrupted the wealth-producing process. It more likely accelerated it in the long run by providing yet more incentives to the use of nonhuman power, metals and laborsaving