In civil engineering, Leonardo produced designs for truss bridges, plans for making the Arno navigable by ocean ships all the way to Florence, swiveling cranes for building construction, a domed church ringed with chapels, and a model city plan with streets on two levels.78 Sketches of an array of scientific instruments-hydrostatic balances, pedometers, hygrometers, anemometers-show the appreciation by Leonardo (and others who made similar drawings) of the need for instrumentation in research, a need destined not soon to be met. Sketches of an array of scientific instruments-hydrostatic balances, pedometers, hygrometers, anemometers-show the appreciation by Leonardo (and others who made similar drawings) of the need for instrumentation in research, a need destined not soon to be met.

Aside from their quant.i.ty, eclipsing the output of any of his contemporaries, the quality of Leonardo's sketches, "miraculously precise and graceful," gives the notebooks a unique distinction. But from the viewpoint of the history of technology, perhaps their most interesting aspect is the author's vision of the relationship between science and technology. "He perceived the need for a.n.a.lyzing the more complex machinery of the day," says Bertrand Gille, "and attacking the problems of friction, stress in materials, reduction and augmentation of power, and transformation of motion."79 His observations were acute and tireless; just as in attempting to design a flying machine he carefully imitated the movements of birds, so in striving to mechanize textile machinery he studied the movements of the clothworkers. His observations were acute and tireless; just as in attempting to design a flying machine he carefully imitated the movements of birds, so in striving to mechanize textile machinery he studied the movements of the clothworkers.

Unfortunately, through a series of accidents Leonardo's notebooks remained unpublished and almost unknown until centuries after his death; some of the most important were rediscovered in a Madrid archive as late as 1967. Consequently, most of his conceptions never bore fruit. Yet relatively little was lost. The work of Leonardo's colleagues, from whom he himself had freely borrowed, continued without interruption to be copied, adapted, and, by later ethical standards, plagiarized. Francesco di Giorgio Martini's sketches of a roller mill, a horse treadmill, and a suction pump were copied without attribution in sixteenth- and seventeenth-century books and, pa.s.sing to the East, were incorporated into the great Chinese encyclopedia of 1726, symbolizing the transformation that had taken place in the technological relationship of East and West.80 Thus, even if the specific ideas depicted in Leonardo's notebooks had little impact, the spirit that created them, "the irrepressible taste for mechanical achievements" shared by Leonardo and his fellow artist-engineers, their "constant and generalized preoccupation with machines and mechanical solutions" (Carlo Cipolla) had tremendous influence.81 True, "the engineers' drawings [were] sometimes more advanced than their practical achievements" (Bertrand Gille), True, "the engineers' drawings [were] sometimes more advanced than their practical achievements" (Bertrand Gille),82 but their conceptual renderings were often legitimate auguries of the future (even Leonardo's bravura conception of a bridge over the Golden Horn at Constantinople has been realized in the twentieth century). The quant.i.ty and quality of their ideas "self-reinforced" (Cipolla); the stream of books on mechanics became, in the two centuries that followed, and with the aid of the printing press, a torrent. but their conceptual renderings were often legitimate auguries of the future (even Leonardo's bravura conception of a bridge over the Golden Horn at Constantinople has been realized in the twentieth century). The quant.i.ty and quality of their ideas "self-reinforced" (Cipolla); the stream of books on mechanics became, in the two centuries that followed, and with the aid of the printing press, a torrent.

Fifteenth-century Technology: Incremental Gains The innovations actually introduced into the technology of the fifteenth century stand in contrast to the freewheeling ideas of the artist-engineers. Where the drawings in the sketchbooks soar beyond the existing means of realization, the changes introduced in the forges, workshops, and mines were nearly all small, practical, and incremental. Some were among the more down-to-earth of the inspirations of the artist-engineers, some were products of more obscure working engineers, and some were contributions of anonymous smiths, masons, and craftsmen. Wider diffusion of many devices is reflected in their familiar treatment in iconography, such as the carpenter's brace and bit (crank application) shown in a basket carried by a Roman soldier in Meister Francke's Carrying the Cross Carrying the Cross (1424). (1424).83 Taken all together, the incremental improvements, newfound applications, and wider diffusion added up to significant advance through the century and pointed the way to the future no less than did the imaginative renderings of Leonardo and his peers. Taken all together, the incremental improvements, newfound applications, and wider diffusion added up to significant advance through the century and pointed the way to the future no less than did the imaginative renderings of Leonardo and his peers.

The turbine, a conception of Francesco di Giorgio, was actually put to work, though for an unexpected purpose. An advanced version of the waterwheel, deriving power from water (or gas) pa.s.sing through it to spin an outer runner (rotor) armed with blades, the turbine eventually powered steamships and electric generators, but its fifteenth-century function was to serve as a turnspit governor; the hotter the fire burned, the faster the hot gas spun the turbine above and turned the roast.84 In this version of a paddleboat sketched by Mariano di Jacopo Taccola, the current turns the paddle wheels, which reel in the rope, propelling the boat upstream (the man helps by pulling on the rope). [Bibliotheque Nationale, Ms. lat. 7239, f. 87.]

Leonardo proposed employing the turbine principle in a centrifugal pump to create a vortex high enough to spill over the containing vessel, as a means of draining swamps. By this time an anonymous inventor, probably in the Low Countries, had come up with a more practical idea: a radically improved windmill design. The tower, or hollow-post, mill mounted the mill mechanism in a revolving turret that could be turned without needing to move the entire structure. The water was lifted either by the scoop action of a vertical wheel or by an Archimedes' screw.85 The other great prime mover, the waterwheel, continued to expand its functions, creating lakes and streams (and sometimes impeding navigation) while powering industrial operations that now included smelting, forging, cutting, shaping, grinding, and polishing metals. It helped produce beer, olive oil, mustard, paper, coins, wire, and silk; it lent its powerful a.s.sistance to fulling cloth, sawing wood, boring pipes, and (by around 1500) ventilating mines. It supplied the power for an improvement in city water supply that began in south Germany with the introduction of piston pumps driven by undershot waterwheels.86 The Chinese treadmill-paddle-wheel boat, an application of the waterwheel in reverse, either reached Europe in the fifteenth century by stimulus diffusion (as Needham believes) or was independently invented. It appears in several ma.n.u.scripts of the artist-engineers and in the following century was built in Spain, where it was long used for harbor transport.87 Cutaway model of man-powered paddle-wheel boat, after a sketch by Leonardo da Vinci, in the Museo della Scienze e della Tecnica, Milan.

One of waterpower's most important fifteenth-century applications probably came in the task of pumping out mine shafts.88 Of the variety of pumps, bucket chains, animal treadmills, and windla.s.s-powered devices shown in Agricola's cla.s.sic Of the variety of pumps, bucket chains, animal treadmills, and windla.s.s-powered devices shown in Agricola's cla.s.sic De re metallica De re metallica (On metallic matters), published in 1556, some were certainly in operation in the fifteenth century. A famous one was designed by Jacob Thurzo of Cracow to deal with the chronic water inrushes of the deep silver-lead mines of the Carpathians in Hungary: an endless two-drum bucket chain powered by an animal treadmill. The device became the technical basis for a major new mining enterprise of Jacob Fugger, the moneyman of Augsburg, financial backer of Maximilian of Habsburg. (On metallic matters), published in 1556, some were certainly in operation in the fifteenth century. A famous one was designed by Jacob Thurzo of Cracow to deal with the chronic water inrushes of the deep silver-lead mines of the Carpathians in Hungary: an endless two-drum bucket chain powered by an animal treadmill. The device became the technical basis for a major new mining enterprise of Jacob Fugger, the moneyman of Augsburg, financial backer of Maximilian of Habsburg.89 Another anonymous innovation that appeared in the metal mines was the wagon mounted on wooden rails, drawn, until the arrival of the steam engine, by animal power. The fifteenth-century carriage makers supplied the future railroad with the pivoted front axle, ancestor of the bogie.90 In 1451 in the Austrian Tyrol, Johannes Funcken invented a new smelting technique to separate silver from lead, an improved version of the cupellation process used by the Romans and described by Theophilus Presbyter. It involved heating cakes of lead, copper, and silver to run off into ladles in which an experienced smelter could separate out the silver. The process supplied another technical a.s.sist to Jacob Fugger's mining and metallurgical enterprise and to the Habsburg hegemony in central Europe.91 The even better mercury amalgam process arrived in time to aid in the Spanish exploitation of American silver mines, also to the benefit of the Habsburgs. The even better mercury amalgam process arrived in time to aid in the Spanish exploitation of American silver mines, also to the benefit of the Habsburgs.

As the blast furnace and refinery delivered an increasing supply of iron to the forge, the smith received help in handling it from the waterwheel via a new device (old in China), the tilt hammer, or trip-hammer. A heavy iron head on a wooden shaft was lifted and released by a drum armed with cams. Rising, it struck a wooden spring beam; the spring's recoil added force to the downstroke. Alternatively an iron block in the floor under the hammer tail achieved the same result.92 Around 1500, and probably before, the slitting mill made its appearance in the iron-rich Liege district. The demand for nails was increasing; the new mechanism provided the smith with slender rods easily converted into nails. It consisted basically of a pair of rotary disk cutters turning in opposite directions. "The first piece of true machinery after the power hammer to be introduced...of even greater importance, it contained the elements of the rolling mill" (W. K. V. Gale). In fact, it gave birth to the rolling mill: two iron cylinders powered by waterwheel flattening a bar of iron pa.s.sed between them.93 Into modern times, the rolling mill remained a basic tool of the iron and steel industry. Into modern times, the rolling mill remained a basic tool of the iron and steel industry.

In the year 1500 iron production for the whole of Europe amounted to the impressive figure of 60,000 tons, according to the estimate of Rupert Hall. Nor was iron the only metal experiencing a boom. Church bells and cannon created a demand for bronze that stimulated larger and larger installations. Both bells and cannon required large quant.i.ties of metal and a high degree of skill; bell metal, 23 to 25 percent tin, depended on precision in casting to ensure the proper ring.94 Among Leonardo's sketches are a reverberatory furnace (one in which the ore is not in contact with the fuel) to produce large quant.i.ties of metal for bell founding and cannon casting, and a crucible furnace in which six crucible pots were aligned in a sloping flue up which the flame swept "like a blowtorch." Among Leonardo's sketches are a reverberatory furnace (one in which the ore is not in contact with the fuel) to produce large quant.i.ties of metal for bell founding and cannon casting, and a crucible furnace in which six crucible pots were aligned in a sloping flue up which the flame swept "like a blowtorch."95 Tilt hammers, sketched by Leonardo. [From Codex Atlanticus, 21 r.a. Science Museum, London.]

Leonardo's "furnace of the controlled flame," in which six crucible pots were aligned in a sloping flue. Model in the Museo della Scienze e della Tecnica, Milan.

The expansion of mining and metallurgy benefited agriculture by increasing the number of tools available and reducing their cost. Metal implements of every sort "figured a great deal more commonly in the everyday life of the sixteenth century than in that of the fourteenth."96 A peasant anywhere in Europe had a far better chance than his great-grandfather of owning not only the basic complement of farm tools but plow and cart (not to mention horses and oxen). A peasant anywhere in Europe had a far better chance than his great-grandfather of owning not only the basic complement of farm tools but plow and cart (not to mention horses and oxen).

In the wake of the Black Death, land too became cheaper, leading to two significant changes in land use. One was the shift to sheep farming, especially widespread in England, where open-field villages were enclosed, the inhabitants sent packing by the new owners, and the land turned over to the sheep. Shepherds and their dogs moved into the manor house while the village dwellings slowly fell to pieces. A second change, especially noticeable in central Germany, was the regeneration of forest where clearings were abandoned for lack of labor to cultivate them. Scrub birch and hazel took over the empty fields, to be replaced in time by beech and other tall forest trees. Georges Duby writes, "The return of natural vegetation in the fourteenth and fifteenth centuries is an episode...of equal importance to the adventure of clearing the wastes."97 The enclosure movement reflected the continued growth of the textile industry, which in the course of the fifteenth century improved both its spinning and its weaving instruments and introduced changes in the organization of work. New patterns of consumption developed, and geographical shifts in manufacture took place.98 An attachment to the spinning wheel, the flyer spindle, sketched by Leonardo and once believed to have been invented by him, is now known to have been borrowed from the silk-throwing process and long used in spinning wool in northern Italy. In this device, as the spindle turned, a flyer-a fork with toothed projections-revolved around it at a different speed, giving the yarn an extra twist. Fork and spindle were moved by separate wheels, powered by the same transmission belt but turning at different rates because of their different diameters.99 The final medieval improvement to the spinning wheel, probably occurring late in the fifteenth century, was the addition of a treadle to power the wheel, leaving the spinner's right hand free to regulate the delicate task of feeding the raw material to the spindle. The result was a product that was more regular and of better quality.100 In the organization of work, while the putting-out system survived in eastern Europe, it was gradually replaced in the West by the beginnings of a true factory system. In some places the factory was partly dispersed; in Florence a cadre of finishers was employed in the merchant's shop while the weavers continued to work in their own homes. In both home and workshop, bells rang for the beginning and end of the working day as well as for meals, and inspectors regularly monitored all the workers.101 In a second form of factory that appeared in England, the sheep-raising landowner established production on his own manor, outside the jurisdiction of both city and guild regulations. At first, as in Florence, the workers labored in their homes and were visited by inspectors. Later they sometimes operated in a central workshop such as the one described, factually but with considerable exaggeration, in the sixteenth-century ballad "The Pleasant History of John Winchcomb, Called Jack of Newbury." The establishment of Jack of Newbury (d. 1519), according to the ballad, was equipped with a thousand looms and employed over a thousand persons, all under one roof. More reliable accounts describe similar but more modest arrangements. The historian John Leland (c. 15061552) tells of an entrepreneur who installed his textile factory in an abbey, in which "every corner of the vast houses...be full of looms." Later the same man acquired another monastery, laying out streets around it, each dedicated to a special function of cloth production.102 As wages rose and prices fell in the aftermath of the Black Death, patterns of consumption shifted. The wool and silk industries found it profitable to produce less expensive fabrics to appeal to middle-cla.s.s customers, while cotton and linen manufacturers exploited the lower end of the market, providing peasant households with bedding, table linen, and undergarments to take the place of their traditional homespun. To serve the new customers, cloth-making centers specializing in cheaper grades sprang up in England, Holland, Germany, France, Spain, and Switzerland.103 The northern Italian cotton industry received compet.i.tion from southern Germany in the form of cheap but durable fustian, a mixture of linen and cotton known in Europe for at least three centuries but now ma.s.s-produced. The German fabric was woven with a warp of local linen fibers and a weft of cotton yarn imported from Venice and Milan. Later the weft was also produced locally, spun from bales of raw cotton bought in northern Italian ports and transported over the Alps. The German fustian industry, which founded several fortunes including that of the Fuggers, was decentralized and largely rural. Merchant capitalists in the towns employed numbers of weavers in the countryside, who enlisted local spinstresses to spin the cotton weft thread and bought linen warp in the local market. The weavers were "less skilled, less supervised, and more poorly paid" than those of the Italian cities, accounting for the lower quality and price of their product, which gradually undermined the Italian cotton industry. A shift completed in the sixteenth century moved cotton from the Mediterranean ports and Italian cities to the Atlantic ports and northern Europe, with raw material beginning to come from the New World.104 Another, quite different, ancestor of modern ma.s.s production appeared in Venice. In the Venetian a.r.s.enal the arming and equipping of war galleys was accomplished by a primitive form of the a.s.sembly line. A Spanish visitor, Pero Tafur, wrote an account of the operation that he observed in 1436: As one enters the gate there is a great street on either hand with the sea in the middle, and on one side are windows opening out of the houses of the a.r.s.enal, and the same on the other side, and out came a galley towed by a boat, and from the windows they handed out...from one the cordage, from another the bread, from another the arms, and from another the ballistas and mortars, and so...everything that was required, and when the galley had reached the end of the street...she was equipped from end to end. In this manner there came out ten galleys, fully armed, between the hours of three and nine.105 In civil engineering, Renaissance architecture created a building boom whose princ.i.p.al technical advances came in lifting machinery, such as the counterweighted pulley hoist devised by Brunelleschi which allowed a rope drum to reverse and set down a load without disturbing the motion of the winch or animal treadmill and which delivered stone blocks, brick, lime, sand, and water for the cupola of the Florentine Duomo. Two pinions, an upper and a lower, could be made to connect with a large wheel, lifting the load or the counterweight.106 System of portcullis lock gates, sketched by Francesco di Giorgio. [Trattato dell'architettura, Codex Ashburnham, 361 f., 41a. Biblioteca Medicea-Laurenziana, Florence.] Codex Ashburnham, 361 f., 41a. Biblioteca Medicea-Laurenziana, Florence.]

The long-standing problem of lock gates was mastered by an idea from China, given perfection by Leonardo. Early lock gates, either simple double doors swinging on hinges or vertical portcullises that lifted straight up, offered insufficient resistance to the pressure of water on the upstream side of the lock basin, and the portcullis type had the disadvantage of needing a high clearance for boats. The Chinese design that reached the West in the fourteenth century provided double doors facing upstream at an obtuse angle, so that the pressure of the stream only forced them more tightly together. Leonardo, after studying the locks in the Visconti ca.n.a.l system around Milan, added a stylish touch: mitered gate edges that met in a snug fit. Water was admitted to the lock basin through small sluices cut in the gate.107 Leonardo's mitered ca.n.a.l lock-gates. [From Codex Atlanticus, 240 r.c. Science Museum, London.]

The mechanical clock spread rapidly in the fifteenth century, becoming a feature of private houses as well as royal palaces and communal towers.108 A late-fifteenth-century invention, the mainspring, second in importance only to the escapement, made timepieces not only portable but cheap. A late-fifteenth-century invention, the mainspring, second in importance only to the escapement, made timepieces not only portable but cheap.109 The pocket version got its name "watch" from the town watchmen who took to carrying it. The pocket version got its name "watch" from the town watchmen who took to carrying it.110 But although the watches had alarms and struck the hours, they kept only indifferent time. The trouble lay in the variable torque of the mainspring, which grew weaker as it unwound. The solution lay in the fusee, a device sketched by Konrad Kyeser in But although the watches had alarms and struck the hours, they kept only indifferent time. The trouble lay in the variable torque of the mainspring, which grew weaker as it unwound. The solution lay in the fusee, a device sketched by Konrad Kyeser in Bellifortis Bellifortis as part of a crossbow and applied to clockwork in Prague in 1424: it was a cone around which a cord connected to the spring was wound. As the spring uncoiled, the diameter of the cone increased, augmenting the leverage and compensating for the weakening of the spring's pull." as part of a crossbow and applied to clockwork in Prague in 1424: it was a cone around which a cord connected to the spring was wound. As the spring uncoiled, the diameter of the cone increased, augmenting the leverage and compensating for the weakening of the spring's pull."111 The earliest application of the mechanical clock to scientific use came in 1484 when Walterus, landgrave of Hesse, another prince with scientific and technological interests, measured the interval between the transits of the sun from noon to noon, using a mechanical clock.112 Fusees and clock mechanism, on right, sketched by Leonardo (on the upper left, a finned explosive projectile). [M. B, f 50v. Science Museum, London.]

In the decorative arts, two landmark technical innovations appeared. Oil as a painting medium was mentioned by Theophilus Presbyter in the twelfth century, but egg-based tempera reigned supreme until a process for refining linseed oil, producing volatile solvents, was developed, mainly in Venice. Pigments dispersed in the treated oil created a responsive medium, exploited early by the Van Eyck brothers in Bruges and a number of artists in Italy (and seized on by Gutenberg for printer's ink).

The maturing of the casting art encouraged the creation of bronze statuary; the first equestrian figure to grace a public square, a statue of the Florentine condottiere Erasmo Gattamelata, was executed in 1453 by Donatello, who also cast a statue of David for the Medici palace, the first bronze fountain piece of the modern world.113 Thus medieval technology made a direct contribution to art. It made a larger indirect contribution in helping to create such fortunes as that of the Medici. Besides Donatello's statue of David, Cosimo de' Medici (13891464) commissioned several madonnas by Fra Lippo Lippi, frescoes by Fra Angelico (for the monastery of San Marco), one of the first great equestrian frescoes, by Andrea del Castagno, a madonna by Flemish master Rogier van der Weyden, terra-cotta reliefs depicting the labors of the field, by Luca Della Robbia, and for his private chapel a Procession of the Magi that included portraits of members of the Medici family, by Benozzo Gozzoli.114 The Ocean Ship European seaborne commerce expanded in every dimension in the fifteenth century: more ships, larger tonnages, better port facilities. Quayside loading and unloading of sailing ships was now established in northern, southern, and Atlantic ports. The Low Countries pioneered technology for harbor maintenance, such as the dredge built by the Dutch to sc.r.a.pe the harbor bottom at Middelburg with a ponderous rake, loosening silt to be carried out by tidal current. Leonardo sketched a more sophisticated solution in the form of a twin-hulled dredge with scoops mounted on a vertical drum, but effective instruments awaited the next century.115 Model of Flemish carrack, c. 1480, with lateen sail on mizzen mast, and stern rudder. [Science Museum, London.]

By far the most important new element in navigation was the full-rigged ship, "the great invention of European ship designers in the Middle Ages" (Richard Unger),116 which "enabled Europeans to harness the energy of the wind over the seas to an extent inconceivable to previous times" (Carlo Cipolla). which "enabled Europeans to harness the energy of the wind over the seas to an extent inconceivable to previous times" (Carlo Cipolla).117 Its princ.i.p.al fifteenth-century form, the carrack, represented the final step in the centuries-long evolution of the round ship: essentially the northern cog, as modified by Mediterranean builders, with further refinements added by Basque shipbuilders of the Bay of Biscay. A large, heavy tub with a big spread of canvas, the carrack had a stout length-to-breadth ratio of three and a half to one or less. The ma.s.sive skeleton ribs that framed its hull, now carvel-built in northern as in southern yards, supported two or even three decks. A majestic sterncastle rose aft of the mainmast, balanced by a smaller but higher forecastle. Its princ.i.p.al fifteenth-century form, the carrack, represented the final step in the centuries-long evolution of the round ship: essentially the northern cog, as modified by Mediterranean builders, with further refinements added by Basque shipbuilders of the Bay of Biscay. A large, heavy tub with a big spread of canvas, the carrack had a stout length-to-breadth ratio of three and a half to one or less. The ma.s.sive skeleton ribs that framed its hull, now carvel-built in northern as in southern yards, supported two or even three decks. A majestic sterncastle rose aft of the mainmast, balanced by a smaller but higher forecastle.118 Its edge-to-edge planking was tightly caulked with oak.u.m (shredded hemp) and tar or pitch and given an outer protection of wales and skids to cushion the collision with the quay. Its edge-to-edge planking was tightly caulked with oak.u.m (shredded hemp) and tar or pitch and given an outer protection of wales and skids to cushion the collision with the quay.119 Few hatches and no companionway helped make it watertight in heavy weather. Few hatches and no companionway helped make it watertight in heavy weather.120 The tiller that operated its sternpost rudder pa.s.sed through a port in the stern to a whipstaff. The tiller that operated its sternpost rudder pa.s.sed through a port in the stern to a whipstaff.

Of its three masts, the main and foremast were square-rigged and supplied most of the power. The mizzen, rising from the sterncastle, was lateen, for control. The huge mainsail hung from a yard as long as the ship itself, below a much smaller topsail; the foremast carried a single square sail. By the end of the century another small sail, the spritsail, on the bowsprit, a.s.sisted the lateen in control.121 Genoa and Ma.r.s.eilles were reputed sources of the best sailcloth (cotton or linen canvas). The square sails were now easier to handle, thanks to improvements in the ropes. The mainsail could even be used to a.s.sist the tacking maneuver; as the ship came into the wind, it was raised momentarily to swing the bow over to the new tack. Genoa and Ma.r.s.eilles were reputed sources of the best sailcloth (cotton or linen canvas). The square sails were now easier to handle, thanks to improvements in the ropes. The mainsail could even be used to a.s.sist the tacking maneuver; as the ship came into the wind, it was raised momentarily to swing the bow over to the new tack.122 The multiplicity of sails proved invaluable when it came to navigating narrow waters, and did not demand more crew, since the sails were worked one at a time. The multiplicity of sails proved invaluable when it came to navigating narrow waters, and did not demand more crew, since the sails were worked one at a time.123 The best bulk carrier yet built anywhere, the carrack could take up to a thousand tons of wheat, salt, and timber in its capacious hold.124 Ranging freely and securely from the Baltic to the eastern Mediterranean, entirely supplanting the sail-and-oar galley on the Italy to Flanders run, it supplied the critical means for implementing the new interdependence of the economies of northern and southern Europe. Ranging freely and securely from the Baltic to the eastern Mediterranean, entirely supplanting the sail-and-oar galley on the Italy to Flanders run, it supplied the critical means for implementing the new interdependence of the economies of northern and southern Europe.

Columbus's Santa Maria Santa Maria was a carrack, though one of quite modest proportions, probably not much more than a hundred tons. His two smaller ships; the was a carrack, though one of quite modest proportions, probably not much more than a hundred tons. His two smaller ships; the Nina Nina and and Pinta Pinta, were products of a second, parallel line of development that began about 1440.125 The caravel was a shipbuilder's solution to a very specific navigation problem: that encountered by Portuguese mariners groping their way down the west coast of Africa in search of the pa.s.sage eastward to Asia. Carrying mixed or lateen rig and weighted with a cargo of no more than fifty tons, the slim caravel (the name a reminder of its carvel construction) had excellent sailing characteristics, including an ability to sail close to the wind that greatly facilitated the return voyage north to Portugal. Before the wind it was capable of a speed of up to eleven knots. Columbus's The caravel was a shipbuilder's solution to a very specific navigation problem: that encountered by Portuguese mariners groping their way down the west coast of Africa in search of the pa.s.sage eastward to Asia. Carrying mixed or lateen rig and weighted with a cargo of no more than fifty tons, the slim caravel (the name a reminder of its carvel construction) had excellent sailing characteristics, including an ability to sail close to the wind that greatly facilitated the return voyage north to Portugal. Before the wind it was capable of a speed of up to eleven knots. Columbus's Nina Nina and and Pinta Pinta, returning from America in 1493, made a day's run of 198 miles.126 The caravel's small crew and minimum supply requirements suited it to exploration of unknown and distant waters, and its maneuverability allowed it to fight off a lee sh.o.r.e even better than could the carrack. The caravel's small crew and minimum supply requirements suited it to exploration of unknown and distant waters, and its maneuverability allowed it to fight off a lee sh.o.r.e even better than could the carrack.

The magnetic compa.s.s was now a mature navigation instrument. The fact that the needle did not point exactly north had been duly noted and allowed for; since no one knew why it pointed north in the first place, the discovery made little difference.127 Simplified versions of the astrolabe and its variant, the quadrant, measured the angles of the two Guardians in relation to the North Star; the resulting data used in conjunction with tables gave lat.i.tude within about twenty-five miles. Simplified versions of the astrolabe and its variant, the quadrant, measured the angles of the two Guardians in relation to the North Star; the resulting data used in conjunction with tables gave lat.i.tude within about twenty-five miles.128 As the Portuguese African ventures reached further and further south, they proved the earth's sphericity beyond a cavil by sighting new constellations, including the spectacular Southern Cross, but lost their ancient guiding light, the North Star. In 1484 King John II appointed a commission of mathematicians to study the problem and draw up tables of declination of the sun to be used at sea in conjunction with the astrolabe or quadrant; by determining the sun's height at midday and consulting the tables, sailors could ascertain lat.i.tude. As the Portuguese African ventures reached further and further south, they proved the earth's sphericity beyond a cavil by sighting new constellations, including the spectacular Southern Cross, but lost their ancient guiding light, the North Star. In 1484 King John II appointed a commission of mathematicians to study the problem and draw up tables of declination of the sun to be used at sea in conjunction with the astrolabe or quadrant; by determining the sun's height at midday and consulting the tables, sailors could ascertain lat.i.tude.129 A new navigation technique was born: the skipper first sought the correct lat.i.tude for a certain port or point of land, then ran along the line of lat.i.tude to his target destination. A new navigation technique was born: the skipper first sought the correct lat.i.tude for a certain port or point of land, then ran along the line of lat.i.tude to his target destination.130 To the tables of declination were added charts of known coasts and pilotage information. Arab and Chinese pilots of the Indian Ocean already knew how to find lat.i.tude, but they never adopted the European custom of carrying charts on board that made it easy to repeat an exploratory voyage with high accuracy. To the tables of declination were added charts of known coasts and pilotage information. Arab and Chinese pilots of the Indian Ocean already knew how to find lat.i.tude, but they never adopted the European custom of carrying charts on board that made it easy to repeat an exploratory voyage with high accuracy.

Despite the advances, navigation at the end of the century still demanded much in the way of experience, judgment, and instinct. Liberation from dead reckoning required a means of determining longitude, which awaited the invention of the chronometer in the eighteenth century. The advances of the fifteenth made it possible, not easy or safe, to explore the immense Ocean Sea and its rumored, but unnamed and uncharted, coasts and islands. But what technology makes possible, someone undertakes.

General knowledge of geography was expanded by publication in Latin in 1406 of the tardily translated Guide to Geography Guide to Geography of Ptolemy, who had compiled his gazetteer-atlas-world-map information in the second century of Ptolemy, who had compiled his gazetteer-atlas-world-map information in the second century A.D. A.D. Necessarily sketchy and inaccurate, it nevertheless added considerable detail to medieval knowledge. Ptolemy's errors did not all go undetected; Pope Pius II (reigned 14581464) exposed one, that of an Indian Ocean landlocked by a dim southern continent. Most significantly, while strengthening the perception of a spherical earth, Ptolemy perpetuated the optimistic reduction of its size and proportion of water made by Marco Polo and Pierre d'Ailly. Columbus, who studied all three authorities, and was prejudiced to begin with, inevitably accepted their calculations. The oldest extant map in the form of a globe, made by Martin Behaim, a German who had been long resident at the Portuguese court, was of equally little help. Columbus took a Behaim globe with him aboard the Necessarily sketchy and inaccurate, it nevertheless added considerable detail to medieval knowledge. Ptolemy's errors did not all go undetected; Pope Pius II (reigned 14581464) exposed one, that of an Indian Ocean landlocked by a dim southern continent. Most significantly, while strengthening the perception of a spherical earth, Ptolemy perpetuated the optimistic reduction of its size and proportion of water made by Marco Polo and Pierre d'Ailly. Columbus, who studied all three authorities, and was prejudiced to begin with, inevitably accepted their calculations. The oldest extant map in the form of a globe, made by Martin Behaim, a German who had been long resident at the Portuguese court, was of equally little help. Columbus took a Behaim globe with him aboard the Santa Maria Santa Maria, but it gave him false rea.s.surance on the size of the oceans and was even curiously out of date on details of the coast of Africa.

Misconceptions still linger about the "spice trade" that motivated the voyages of discovery. Europeans have been credited with an insatiable appet.i.te for seasonings, attributed either to monotony of diet or to a need to disguise the taste of meat that was thought to have chronically spoiled owing to lack of refrigeration. Both notions contain only a particle of truth. The peasant diet was certainly monotonous, but peasants could not afford imported spices. The diet of the well-to-do, the customers for spices, was a different matter: meat and fish at all seasons, and a list of fruits and vegetables that increased through the Middle Ages (oranges and lemons early, lettuce in the fourteenth century, artichokes and cantaloupe in the fifteenth), even before the influx of new products from the Americas. The popular Tacuinum sanitatis Tacuinum sanitatis (Health handbook), which appeared in many fourteenth-century versions, also mentions among its vegetables and fruits spinach, asparagus, leeks, turnips, pomegranates, watermelons, cuc.u.mbers, green squash, sour cherries, cabbage, beets, and chestnuts. (Health handbook), which appeared in many fourteenth-century versions, also mentions among its vegetables and fruits spinach, asparagus, leeks, turnips, pomegranates, watermelons, cuc.u.mbers, green squash, sour cherries, cabbage, beets, and chestnuts.131 In respect to food preservation, medieval Europe was hardly worse off than nineteenth- and early-twentieth-century Europe and America. A number of techniques were available: smoking, salting, and drying, and also on-the-hoof preservation-oxen, goats, sheep, poultry, and pigs driven live to city markets, game and domestic animals killed and eaten forthwith. Affluent households in town and country stocked fish tanks and ponds. There was little need to disguise spoiled meat (which the wealthy would have refused to eat). There was, however, a need to add flavor to meat that was usually subjected to long cooking in liquid because of its toughness.

That fact alone hardly explains the importance of the spice trade. The real keys to the mystery are two. The first is the physical character of spices: extreme compactness in proportion to value, and resistance to spoilage. Though not outrageously expensive to the consumer-a little pepper or saffron goes a long way-they carried very high price tags for the amount of cargo s.p.a.ce they took up. This was a consideration of overriding importance when most ships could carry no more than a hundred or two hundred tons. A merchant reserving cargo s.p.a.ce aboard a Venetian or Genoese vessel on the Syria run filled his quota with the most valuable merchandise per weight that he could find: gold and silver ornaments, jewelry, silk, and spices.

The second key to the mystery is a matter of vocabulary. The medieval use of the word "spices" covered a vast mult.i.tude of useful commodities, only a portion of which were destined for the cooking pot. Robert Lopez summarizes them as "seasonings, perfumes, dyestuffs, and medicinals."132 Florentine merchant Frances...o...b..lducci Pegolotti's Florentine merchant Frances...o...b..lducci Pegolotti's La pratica della mercatura La pratica della mercatura (The practice of commerce), in its comprehensive list of 288 "spices" carried in fourteenth-century commerce, enumerates, alongside anise, cinnamon, c.u.min, ginger, cloves, nutmeg, pepper, sugar, fennel, and citron, such pharmaceuticals, dyes, industrial additives, and miscellaneous items as camphor, wax, alum, rosewater, cotton thread, paper of Damascus, glue, ivory, indigo, frankincense, sh.e.l.lac, musk, linseed oil, niter salt, soda ash, soap, turpentine, Venetian copper, nux vomica, and gold leaf. (The practice of commerce), in its comprehensive list of 288 "spices" carried in fourteenth-century commerce, enumerates, alongside anise, cinnamon, c.u.min, ginger, cloves, nutmeg, pepper, sugar, fennel, and citron, such pharmaceuticals, dyes, industrial additives, and miscellaneous items as camphor, wax, alum, rosewater, cotton thread, paper of Damascus, glue, ivory, indigo, frankincense, sh.e.l.lac, musk, linseed oil, niter salt, soda ash, soap, turpentine, Venetian copper, nux vomica, and gold leaf.133 This large array originated in a wide scattering of sources in India, Indonesia, and southeast Asia, and moved to Europe partly by ship (via the Persian Gulf or Red Sea), partly by caravan or pack train, with many transshipments, many tolls, and much danger of loss. A sea route that would permit a ship to sail from Europe all the way to the "Indies," load up, and sail back with a hold full of "spices" would guarantee a fortune per voyage. This large array originated in a wide scattering of sources in India, Indonesia, and southeast Asia, and moved to Europe partly by ship (via the Persian Gulf or Red Sea), partly by caravan or pack train, with many transshipments, many tolls, and much danger of loss. A sea route that would permit a ship to sail from Europe all the way to the "Indies," load up, and sail back with a hold full of "spices" would guarantee a fortune per voyage.

The spice trade did not begin in the Middle Ages. Pliny comments on the widespread use of pepper, with which Rome was so plentifully supplied and with which the barbarian Goths were so familiar that when Alaric exacted a ransom from the city in 408 he included in his demands 3,000 pounds of pepper.134 Nor did the spices by themselves account for the Age of Exploration. Other motives entered in. Religious proselytizing was as old as Christianity and had won converts, willing or reluctant, among third-century Goths, fifth-century Franks, the wild Vikings of Scandinavia, and the Poles and Magyars of eastern Europe. Whether proselytizing came first and profit second or vice versa may be an open question, but to the lure of spices should be added that of certain other merchandise, notably gold, increasingly needed to fuel the Commercial Revolution. Spanish conquistador Bernal Diaz voiced a Christian-capitalist ideal in expressing the wish "to serve G.o.d and his Majesty, to give light to those who were in darkness, and to grow rich as all men desire to do." A modern historian has evaluated with succinct cynicism: "Religion supplied the pretext and gold the motive" (Cipolla). Nor did the spices by themselves account for the Age of Exploration. Other motives entered in. Religious proselytizing was as old as Christianity and had won converts, willing or reluctant, among third-century Goths, fifth-century Franks, the wild Vikings of Scandinavia, and the Poles and Magyars of eastern Europe. Whether proselytizing came first and profit second or vice versa may be an open question, but to the lure of spices should be added that of certain other merchandise, notably gold, increasingly needed to fuel the Commercial Revolution. Spanish conquistador Bernal Diaz voiced a Christian-capitalist ideal in expressing the wish "to serve G.o.d and his Majesty, to give light to those who were in darkness, and to grow rich as all men desire to do." A modern historian has evaluated with succinct cynicism: "Religion supplied the pretext and gold the motive" (Cipolla).135 The medieval character of exploration and its motives is underlined by the kind of inducements offered to the explorers. The Portuguese kings agreed to give their captains a share in newfound lands along with the profits of civil and criminal justice and the monopoly of mills, ovens, and salt. The letters patent given Venetian John Cabot by the king of England included the governorship of new lands, a monopoly on their produce, and duty-free importation, with a fifth of the profits to go to the Crown.136 Another motive was fishing. Cod disappeared from the coastal waters of Europe just as an improvement in fish-packing technology, a press to pack the salted cod into barrels, was invented. Basque and other fishermen may have found the fabulous codfish grounds of the Grand Banks before Cabot did in 149798 without ever advertising their discovery (as fishermen often do not).137 Finally there was the lure of the unknown but knowable, the opportunity the full-rigged ship gave to find answers to the mysteries that had baffled and fascinated European intellectuals from Ptolemy to Toscanelli. "One of the most powerful incentives for Atlantic exploration was the quest for islands" (J. R. S. Phillips) whose existence had been persistently bruited by sailors and mapmakers.138 That the lead was taken by the new and small kingdom of Portugal was owing partly to Portugal's unique geographical position, fronting the Atlantic but close to the gateway to the Mediterranean, and partly to the progress of the Reconquista. With the last Muslims driven out of Portugal, the natural continuation was to carry the war across the water to North Africa, which the Portuguese did in 1415 by seizing Ceuta, across the strait from Gibraltar. Quite apart from a route to the Indies, Africa itself was worthy of attention as a known source of gold bullion, and the early Portuguese exploration south was oriented to Africa's rather than Asia's wealth.139 Although recent scholarship has somewhat discounted the individual contribution of Prince Henry the Navigator, he remains a remarkable figure, employing funds available to him as master of the Order of Christ to attract geographers and savants to Lisbon and to fit out expeditions. The first fruits were the Madeira Islands to the south, already discovered by the ubiquitous Genoese in the fourteenth century and rediscovered for Portugal in 1418; and the great chain of the Azores (14271431), a third of the way across the Atlantic. Both archipelagos were barren of inhabitants, and both proved highly colonizable, congenial to the cultivation of sugar, one of the most treasured of the spices. The west coast of Africa was reconnoitered by a series of imaginative voyages in which the caravels turned the prevailing winds to advantage by first sailing well out into the Atlantic, then angling back to the African coast, where the few river mouths and inlets were one after another discovered. Trading with the natives netted gold, slaves, and elephant tusks. These last quickly captured the ivory market from the walrus tusks of Greenland, whose Viking colony, hard hit by the Black Death and a prolonged cold wave, gave up and retreated to Iceland. Greenland reverted to its Inuit (Eskimo) natives, thus putting an end to the sterile Scandinavian northern adventure just as the fruitful Portuguese southern adventure was picking up momentum.140 In both directions, west and south, distances proved disconcertingly longer than navigators had been led to believe by the authorities, but in 1488 the Cape of Good Hope was at last rounded, and in 1499 Vasco da Gama, a soldier given charge of a three-ship expedition, made it back to Lisbon with two ships loaded with enough spices to pay for the voyage several times over.

Da Gama's ocean trail was swiftly followed by ships of all the western European nations. Surprisingly, as Fernand Braudel has pointed out, it was not followed in reverse by Asian ships. Large Chinese multisailed and multidecked junks had shown themselves fully capable of long-distance ocean voyaging; Admiral Cheng Huo's fleet made a succession of voyages to India and East Africa between 1405 and 1433. Why the Chinese tamely abandoned the European spice trade to the Europeans remains a historical mystery.141 In the other direction, westward, Portuguese exploration was checkmated by its very success in discovering and colonizing the Azores. Using the Azores as a base, Portuguese mariners trying to sail into the teeth of prevailing winds got nowhere, but a southbound expedition, under Pedro Cabral, taking the usual long southwest tack followed by a return southeast, discovered Brazil. By that time, Columbus, still another Genoese who took service with Portugal, but ultimately sailed for Spain, had put into effect his own adventurous plan, which was to start not from the Azores but from the Canaries, a long-inhabited archipelago several hundred miles south, now in the possession of Spain. From there he was able to pick up favorable winds to carry him to what he imagined to be the islands and coasts of Asia, and to use the westerlies to get back to Spain.

One resounding irony of Columbus's voyage is that the New World produced none of the traditional spices he sought but supplied a trove of entirely new foodstuffs for the European table: maize (corn), potatoes, chocolate, peanuts, tomatoes, pineapples, green beans, lima beans, red and green peppers, tapioca, vanilla, and the turkey. At the same time, America gained many European crops: wheat, barley, broad beans, chick-peas (garbanzo beans), sugarcane. Asia and Africa were brought into the general exchange, Asia receiving sweet potatoes, pineapples, papaya melons, and chili peppers while giving America bananas, rice, and citrus fruits. Africa received maize, manioc, sweet potatoes, peanuts, and green beans, and sent to America yams, cowpeas, coconuts, coffee, and breadfruit.142 Yet another irony: Columbus's voyage, as it turned out, neither depended on nor demonstrated the sphericity of the earth, since he could have made the same trip, Spain to the West Indies and back, on a flat earth.

Whether Columbus was preceded by Irish missionaries, Bristol merchants, Basque fishermen, or anonymous Portuguese explorers was once regarded as worthy of scholarly debate. Today, as better acquaintance with medieval history improves our perspective on the Age of Exploration, it is easy to see that remarkable though Columbus's feat was, the European discovery of "America" was inevitable within a short time, and even without Cabral's fortuitous landfall in Brazil. Motives were sufficient, and means, developed over centuries, were ample.

Conjectural model of Columbus's Santa Maria. Santa Maria. [Science Museum, London.] [Science Museum, London.]

1500 AND AFTER:.

"WESTERN CIVILIZATION"

The America that Columbus discovered for Europe had supported its human population for unknown thousands of years, long enough to develop its own civilizations which in many respects (for example, irrigation agriculture) were remarkable indeed. But its isolation from the rest of the world after the submerging of the Aleutian-Bering Sea crossing had imposed handicaps. The Americas offered no large animals suitable for riding and traction, although the Peruvians had domesticated the little llama for pack carrying. Maize was widely cultivated, but wheat was absent. In most regions tools remained of wood, bone, and stone. In the absence of traction animals, the wheel was not invented (except as a toy); consequently, the wheeled vehicle, the potter's wheel, the spinning wheel, and the waterwheel all remained unknown.

The discrepancy in technological levels conditioned much of the relationship between the European discoverer-adventurers and the native Americans. The first appalling consequences, however, were due to something else: the lack of immunity of the Americans to European diseases-influenza, malaria, measles, and above all smallpox. In Europe mainly a childhood disease that conferred immunity on adult survivors, in America smallpox lethally attacked people of all ages, creating steep, long-range demographic declines.143 These catastrophes were by no means deliberately inflicted; on the contrary, the European invaders wanted a healthy and numerous native population for labor recruitment. Plenty of room for criticism of the treatment of the natives remains, not only, it should be noted, by the Spaniards, who have commonly been made the scapegoats, but by others, including the English and their American descendants. Lack of immunity, incidentally, cut both ways; Columbus's expedition has been credited with bringing back to Europe syphilis, a minor ailment in the Western Hemisphere but a ferocious one in Europe; yellow fever similarly discriminated against the explorer-invaders. These catastrophes were by no means deliberately inflicted; on the contrary, the European invaders wanted a healthy and numerous native population for labor recruitment. Plenty of room for criticism of the treatment of the natives remains, not only, it should be noted, by the Spaniards, who have commonly been made the scapegoats, but by others, including the English and their American descendants. Lack of immunity, incidentally, cut both ways; Columbus's expedition has been credited with bringing back to Europe syphilis, a minor ailment in the Western Hemisphere but a ferocious one in Europe; yellow fever similarly discriminated against the explorer-invaders.144 No pathological disasters followed European expansion in Africa and Asia, which evidently shared immunities with their European neighbors. Not that Africa and Asia had reason to be happy with their visitations; Africa became a source of slaves to work the mining and agricultural enterprises of America, and Asia in due course felt the weight of imperialism. Yet the Europeanization of the world, whatever losses it has entailed along the way, is virtually complete and has been almost universally accepted at least in its material aspect. Few today want to return to the civilizations of Greece and Rome, or to those of the Aztecs and Incas.

Global Europeanization took several centuries and embraced much more than technology. But at the heart of the historical process that wrought the vast alteration lay the slow revolution in tools and processes that transpired in Mediterranean and northwest Europe between the sixth and sixteenth centuries. During that medieval millennium, Europe left the world of Rome far behind, while overtaking China and India. The rising technological level of medieval Europe is reflected in the improvement in daily life and work: from slave labor to free labor, from human drudgery to animal power and waterpower; from luxury handicrafts to ma.s.s production for ma.s.s markets; from handwritten ma.n.u.scripts for a scattering of intellectuals to printed books for a large audience; in metal tools and metalware, profusion in place of scarcity; and a long list of useful novelties, from clocks to ca.n.a.l locks. And, not to overlook the dark side of progress, gunpowder weapons, the one legacy of medieval technology that was indeed "pernicious."

Europe built its new "Western civilization" on a material foundation that it created not merely by borrowing freely from others but by making its borrowings extraordinarily effective. "A technologically progressive society," says D. S. L. Cardwell, "is...both willing and able to accept and apply inventions from whatever source they may come."145 Just how much of Europe's technology actually derived from Asia remains a mystery awaiting scholarly detective work. A comment of Joseph Needham in respect to cast iron may be more widely applied: "Admittedly there is no one clinching piece of evidence, but rather a ma.s.s of hints." Just how much of Europe's technology actually derived from Asia remains a mystery awaiting scholarly detective work. A comment of Joseph Needham in respect to cast iron may be more widely applied: "Admittedly there is no one clinching piece of evidence, but rather a ma.s.s of hints."146 Asian priority in a wide range of innovations is established. Asia, however, showed little inclination to borrow, and so, after giving much to others, allowed its own technology to wither, as demonstrated in the history of the two epoch-making inventions of printing and firearms. Each originated in China, but each was allowed to languish, while Europe seized them in both hands to make them major instruments of change. An authority on technology transfer in the modern world a.s.serts that the process "is not just a matter of moving some piece of hardware from one place to another...A material infrastructure is not enough. There must also be sufficient nonmaterial infrastructure." Asian priority in a wide range of innovations is established. Asia, however, showed little inclination to borrow, and so, after giving much to others, allowed its own technology to wither, as demonstrated in the history of the two epoch-making inventions of printing and firearms. Each originated in China, but each was allowed to languish, while Europe seized them in both hands to make them major instruments of change. An authority on technology transfer in the modern world a.s.serts that the process "is not just a matter of moving some piece of hardware from one place to another...A material infrastructure is not enough. There must also be sufficient nonmaterial infrastructure."147 In the "nonmaterial infrastructure" of medieval Europe was a spirit of progress whose ingredients included intellectual curiosity, a love of tinkering, an ambition "to serve G.o.d" and also "to grow rich as all men desire to do." In the "nonmaterial infrastructure" of medieval Europe was a spirit of progress whose ingredients included intellectual curiosity, a love of tinkering, an ambition "to serve G.o.d" and also "to grow rich as all men desire to do."

A sense of progress implies a sense of history, something missing among the Egyptians, Greeks, and Romans. "Lacking any objective understanding of the past-that is, lacking history," says Cardwell, "the hierarchical and slave-owning societies of cla.s.sical antiquity failed to appreciate the great progress that had been achieved by and through technics."148 On the contrary, the ancients were fond of looking back to what they conceived as a vanished "golden age," a conception the reverse of progress. The Christian Church, whose pioneering monastic orders made many practical and material contributions to medieval technology, also supplied a noncyclical, straight-line view of history that allowed scope for the idea of progress. On the contrary, the ancients were fond of looking back to what they conceived as a vanished "golden age," a conception the reverse of progress. The Christian Church, whose pioneering monastic orders made many practical and material contributions to medieval technology, also supplied a noncyclical, straight-line view of history that allowed scope for the idea of progress.

Optimistic and utilitarian, fifteenth-century Europe's craftsmen, smiths, engineers, and shipbuilders sought better ways to do things, make things, make things work. Carlo Cipolla identifies their keynote: "Machines came to play an increasingly important role in the production process."149 The fifteenth century's Francesco di Giorgio Martini explained why: "Without mechanical ingenuity the strength of man is of small avail." The fifteenth century's Francesco di Giorgio Martini explained why: "Without mechanical ingenuity the strength of man is of small avail."150 Francesco echoed Hugh of St. Victor's concept of man, "naked and unarmed" but equipped with reason in order to supplement his weak powers by invention. Francesco echoed Hugh of St. Victor's concept of man, "naked and unarmed" but equipped with reason in order to supplement his weak powers by invention.

In seeking ways to multiply the feeble strength of man, medieval Europe found its most effective instrument in the vertical waterwheel, the world's chief prime mover until the invention of the steam engine. Neither Rome nor China succeeded in harnessing its power to the extent that medieval Europe did. Terry Reynolds summarizes the encompa.s.sing role it achieved in the high Middle Ages: "The house medieval man lived in might have been made of wood sawed at a hydropowered sawmill...The flour he ate...the oil he put on his bread...the leather of the shoes he put on his feet and the textiles he wore on his back...the iron of his tools...the paper he wrote on" all were produced in part with the aid of waterpower.151 A valuable spin-off from the waterwheel was the encouragement it lent to experimentation with key mechanical auxiliaries: gears, cams, cranks, and flywheels. It did not at once bring on the Industrial Revolution. "There were too many social obstacles and too many technical difficulties for any general mechanization," says Bertrand Gille. "Nevertheless, the progress achieved was far from negligible and marks a considerable advance on the machinery of the ancient world."152 It also promoted the evolution of the blast furnace, indispensable to supplying metal in a volume suitable to a mechanized industry. Such an industry also required skilled and knowledgeable workers; the invention of clockwork contributed to the skill and the invention of printing to the knowledge. As Terry Reynolds summarizes, "The roots from which the modern factory system emerged were quite deeply imbedded in the Middle Ages...there were no sharp breaks between the water-powered fulling and iron mills of the late Middle Ages and the textile mills of Strutt and Arkwright." It also promoted the evolution of the blast furnace, indispensable to supplying metal in a volume suitable to a mechanized industry. Such an industry also required skilled and knowledgeable workers; the invention of clockwork contributed to the skill and the invention of printing to the knowledge. As Terry Reynolds summarizes, "The roots from which the modern factory system emerged were quite deeply imbedded in the Middle Ages...there were no sharp breaks between the water-powered fulling and iron mills of the late Middle Ages and the textile mills of Strutt and Arkwright."153 In its organization of work, too, the high Middle Ages took a giant stride. The putting-out system-the "factory scattered through the town"-and its successor arrangements in Italy, England, and Germany clearly pointed the way to the future. In another dimension, so did the Venetian a.r.s.enal and its pioneering "a.s.sembly line."

The Scientific Revolution of Galileo, Tycho, and Newton also profited from the intellectual and practical contributions of the Middle Ages, notably the invention of the convex lens. "In the Scientific Revolution of the sixteenth and seventeenth centuries," says Derek de Solla Price, "the dominant influences were the craft tradition and the printed book."154 Thus technology served science, foreshadowing a future full partnership of the two. Nor should the role of medieval scientific thought be overlooked. The old picture of modern science springing directly from Aristotle and antiquity has lost validity: "Modern science...is rather the child of medieval science" (Richard Dales). Thus technology served science, foreshadowing a future full partnership of the two. Nor should the role of medieval scientific thought be overlooked. The old picture of modern science springing directly from Aristotle and antiquity has lost validity: "Modern science...is rather the child of medieval science" (Richard Dales).155 Although the age succeeding that of Leonardo witnessed a relaxation of the pace of technical change, the perception of technology gained noticeably in stature, "capturing a place it had never before occupied" (Bertrand Gille).156 For one thing, it had gained political importance, not only in the form of small arms and artillery but in many areas of mining, metallurgy, and craft product