Galluzzi then adds this note: “Scaglia, who describes these projects as a ‘machine complex’ or ‘gear pump and mill complexes’ doubts they can be attributed to Francesco. In her view Francesco probably compiled many of these designs, already developed by the late 1460’s ‘in workshop booklets prepared by carpenters and mill wrights.’”14
Galluzzi is clearly puzzled by Francesco’s improvements on Taccola, which, knowing of no precedents, he attributes to Francesco’s genius. But were there no precedents? Scaglia believes he compiled his designs from workshop booklets. What workshop booklets were available?
My first thought was Roman or Greek booklets. The Renaissance, after all, is said to have been a rebirth of Roman and Greek ideas. Leonardo was said to have slept with all nine volumes of Vitruvius’s De architettura under his pillow. Taccola described himself as the Archimedes of Siena.
Our research team spent weeks in the British Library investigating whether Taccola and Francesco could have copied their array of machines and inventions from Greeks and Romans. Vitruvius was quickly ruled out—he showed no drawings of machines. Our team next searched Archimedes, Vegetius, Dinocrates, Ctesibus, Hero, Athanaeus, and Apollodorus of Damascus but drew a blank. Scaglia, too, found few classical sources for Taccola’s work. “He does not seem to have had direct access to the writings of Archimedes, Hero, Euclid, Vitruvius and The Mechanical Problems,” she concludes.
A number of Taccola’s drawings and di Giorgio’s copies were of gunpowder weapons, which, of course, were unknown to Greece and Rome. This suggested a Chinese source. If there was such a source, could we find it in order to compare it with Taccola and di Giorgio? This was our next line of inquiry. It took months.
If such a Chinese book had existed in Florence in Taccola’s time, it must have been a printed copy—it would have been inconceivable for Zheng He’s fleets to have carted the original book of drawings around the oceans. Like the astronomical calendar and ephemeris tables given to Toscanelli and the pope, it seemed likely that the drawings of machines would also be printed.
We looked for printed books of machines widely available in China at the time of Zheng He’s voyages. The British Library’s electronic database has a number of articles on Ming printing. The Harvard Journal of Asiatic Studies provides a good summary:15
Coming down the centuries we have definitive proof of the manufacture and application of wooden type early in the fourteenth century, as recorded by Wang Chen, a magistrate of Ching-te in Anhwei, from 1285 to 1301. At this place, Wang was writing what was to be his great work, the Nung-shu or Writings on Agriculture, an early and very thorough manual on the arts of husbandry. Because of the large number of characters to be employed, Wang conceived the idea of using movable type instead of the ordinary blocks, thereby reducing labor and expense. In his experiments Wang made more than 60,000 separate types, the cutting of which entailed no less than two years….
In order to record for posterity his experiments in the manufacture of wooden movable type, he included a detailed account of them in his block-print edition, the preface of which was dated 1313.
Although perhaps not in da Vinci’s hand, this drawing of a printing press appears in his notebooks.
The Source of Taccola and Francesco’s Inventions: the Nung Shu16
So in 1313, the world saw its first mass-produced book: the Nung Shu. (Needham implies it became a bestseller.)
Although Mao’s Red Guards made bonfires of these Nung Shu books, Graham Hutt of the British Library kindly helped us find copies. With mounting anticipation I put a weekend aside to study a copy of the Nung Shu and any drawings it might contain.
Opening the book was one of the most thrilling moments in my seventeen years of research. The first drawing was of two horses pulling a mill to grind corn, just as Taccola17 and di Giorgio18 had depicted. With feverish excitement I turned the pages—it was obvious that we had found the source for their machines.
Needham organizes the machines illustrated in the Nung Shu under various rubrics:
The Nung Shu, on the other hand, shows us no less than 265 diagrams and illustrations of agricultural implements and machines…. His Nung Shu is the greatest, though not the largest, of all works on agriculture and agricultural engineering in China, holding a unique position on account of its date [1313].
And hence its freedom from occidental influences.”19
As far as I can see, every variation of shafts, wheels, and cranks “invented” and drawn by Taccola and Francesco is illustrated in the Nung Shu. This is epitomized in the horizontal water-powered turbine used in the blast furnace.20 This complex and sophisticated machine has a horizontal water-drive wheel to which is attached a drive belt. The drive belt powers a subsidiary shaft attached by a pulley to an eccentric crank linked by a crank joint and pushes (through rocking rollers and a piston rod) a fan bellows, which pumps air into the furnace. As Needham says: “We have here a conversion of rotary to longitudinal reciprocating motion in a heavy duty machine by the classical method later characteristic of the steam engine, transmission of power taking place, however in the reverse direction. Thus the great historical significance of this mechanism lies in its morphological paternity of steam power.”
As far as I can determine, every type of powered transmission described by Taccola and di Giorgio is shown in the Nung Shu. There are several examples shown on the 1434 website.
In di Giorgio’s column hoist21 the enmeshing gear wheels, right-angle gearing, pinwheel, and pin drum are employed.
In his illustration of carts with steering gear22 (Codicetto) he shows a crank arm fitted with connecting rods, and enmeshing gear wheels transform horizontal to vertical power.
A Chinese bucket pump.
So many of Taccola’s ideas, including the bucket pump and waterwheel, are uncannily similar to the Nung Shu illustrations.
Taccola’s drawings of reversible hoists23 (De ingeneis) show flat teeth with enmeshing gear wheels transferring horizontal to vertical power, together with a differential windlass and counterweight. Taccola shows the same.
The “vertical waterwheel with vanes”24 illustrates vertical power being transferred to horizontal by enmeshing gear wheels, cranks and connecting rods, cam and cam followers, and right-angle gears.
Di Giorgio’s chain pump activated by animal-powered horizontal wheel25 has scoop wheels on spokes, eccentric lugs, bucket pumps, and continuous drive belts.
That di Giorgio plagiarized both Taccola and the Nung Shu is, in my opinion, supported by the following passage from Galluzzi:
A Chinese animal-powered chain pump.
Taccola’s illustration of an animal-powered chain pump is strikingly similar to the Chinese version.
Beasts of burden made much better workers than humans for some jobs!
Santini’s design mimics and then develops the process somewhat.
The vertical waterwheel is shown to have many applications in the Nung Shu.
A similar vertical waterwheel is found in Taccola’s treatise on machines.
The four basic categories of Francesco’s machines exhibit some interesting new features. First the inclusion of written commentaries enhances the graphic representations of the devices with lexical information of major interest, data on materials and dimensions, special construction hints, and specific applications [the Nung Shu contains written commentaries]…. In some drawings of mills he introduces quantitative analysis on the relationships between teeth, wheel, and pinion diameters.
The author was clearly intent, however, on defining criteria to organise his material—a concern virtually absent not only from Taccola’s work and Francesco’s early writings but also from all prior books about machines [the Nung Shu is organized by criteria]….
The section on mills was most heavily expanded reaching 58 separate items…. The chapter on pumps was similarly expanded in the Trattato I, which discusses a vast range of this kind of device. Conversely the section on carts and “pulling and lift
ing devices” was reduced…. In particular the number of machines for lifting and moving columns and obelisks was drastically cut. The tendency to narrow the discussion to basic examples of each machine type gathered considerable momentum in the so called second draft of the work (Trattato II)…. Only ten illustrations of mills survived, but now they were strictly arranged by energy source: overshot bucket water wheel, horizontal paddle (a ritrecine) wheel, horizontal axis windmill, crank shaft (a frucatoio) mill with a flywheel bearing metal spheres, human-powered and animal powered mills (three designs with different transmission systems) and lastly the horse-powered tread wheel (two designs; one in which the animal moves the wheel from the inside, the other in which the animal applies pressure on the outer rim). [All these mills illustrated by Francesco appear in the Nung Shu.]26
Galluzzi continues:
The successive drafts of the Trattato therefore chart the evolution of Francesco’s technological method from a potentially infinite series of exampla to the definition of a limited number of “types.” Each of these embodied the basic principles of a specific technical system which could then vary ad infinitum to suit the craftsman’s needs. [As di Giorgio himself confirms in Trattato II:] “and with these we conclude the section on instruments for pulling weights in construction work, since from these one can easily derive the others.”27
A Chinese chain pump from the Nung Shu.
Di Giorgio’s chain pump is a copy of Taccola’s and almost identical to the Chinese illustration.
In my opinion di Giorgio started with the animal-powered machines shown in the Nung Shu, which he copied. He then copied from Nung Shu the basic Chinese water-powered machines using horizontal and vertical waterwheels. Next he adapted the horizontal and vertical waterwheels of the Nung Shu to power a whole range of mills and pumps—just as Galluzzi describes.
He did this by using the basic principles shown in the Nung Shu, that is, converting water power from horizontal to vertical through enmeshing gear wheels. Francesco changed power ratios through different sizes of gear wheels and also changed direction through cam shafts and rocker bearings so as to devise an array of water-and animal-powered sawmills and all manner of pumping systems.28
Galluzzi successfully summarizes Francesco’s adaptations; Francesco himself says, “From these we can easily derive the others.”
Leonardo da Vinci Develops Francesco di Giorgio’s Machines
In The Art of Invention Galluzzi reevaluates Leonardo’s place in light of the earlier work of Taccola and di Giorgio:
“Leonardo ceases to be a visionary prophet in the desert. Rather he appears as the man who most eloquently expressed—both with words and above all images—the utopian vision about the practical potential of technology that were enthusiastically shared by many ‘artist engineers’ of the fifteenth century.”29
Leonardo no longer appears as the iconic, singular genius. Instead, as Galluzzi writes, he “emerges as the culmination, as the most mature and original product of a collective development lasting several decades to which many highly talented figures made sizable contributions.”30
I believe Leonardo’s machines were superbly illustrated copies and improvements of di Giorgio’s. He brought his brilliant and incisive mind to penetrate the essentials of these machines, which he regarded not as magic creations deposited from heaven but as assemblages of parts. According to Galluzzi, he was able to perceive that an infinite variety of machines could be derived from a finite number of mechanisms, which he defines as “elements of machines.” As Galluzzi writes, his vision of the anatomy of machines and man was enshrined in a series of masterly drawings that mark the birth of modern scientific illustration.
By comparing Leonardo’s drawings with the Nung Shu, we have verified that each element of a machine superbly illustrated by Leonardo had previously been illustrated by the Chinese in a much simpler manual.
In summary, Leonardo’s body of work rested on a vast foundation of work previously done by others. His mechanical drawings of flour and roller mills, water mills and sawmills, pile drivers, weight-transporting machines, all kinds of winders and cranes, mechanized cars, pumps, water-lifting devices, and dredgers were developments and improvements upon Francesco di Giorgio’s Trattato di architettura civile e militare. Leonardo’s rules for perspective for painting and sculpture were derived from Alberti’s De pictura and De statua. His parachute was based on di Giorgio’s. His helicopter was modeled on a Chinese toy imported to Italy circa 1440 and drawn by Taccola.31 His work on canals, locks, aqueducts, and fountains originated from his meeting in Pavia with di Giorgio in 1490 (discussed in more detail in chapter 18). His cartography evolved from Alberti’s Descriptio urbis Romae. His military machines were copies of Taccola’s and di Giorgio’s—but brilliantly drawn.
Leonardo’s three-dimensional illustrations of the components of man and machines are a unique and brilliant contribution to civilization—as are his sublime sculptures and paintings. In my eyes, he remains the greatest genius who ever lived. However, it is time to recognize the Chinese contributions to his work. Without these contributions, the history of the Renaissance would have been very different, and Leonardo almost certainly would not have developed the full range of his talents.
17
SILK AND RICE
By the time the Nung Shu was published in 1313, the Chinese had been spinning yarns for a thousand years, using all sorts of materials. Silk was the finest and most valuable; scrapings of hides were the heaviest and cheapest. Needham produces diagrams of an array of hand-powered and water-powered spinning machines with single and multiple looms.1
China had been exporting silk to Italy for a millennium by the time Taccola and Franceso di Giorgio appeared. In 115 B.C., Mithridates II of Persia made a commercial treaty with the Han emperor Wu Ti. In the next century, Julius Caesar possessed silk curtains.2 By the reign of Augustus, wealthy people were buried in Chinese silk.3
In return for fine silk, Chinese merchants sought gold, silver, coral, and glass. Chinese regarded high-quality glassware as a great luxury and were prepared to pay accordingly. During the Tang dynasty, monks smuggled silkworms from China to the West. Pictures of quilling machines, which wind silk thread onto bobbins, can be seen in the stained-glass windows of the Chartres cathedral, dating between 1240 and 1245. A clear illustration of the Chinese model is shown in The Genius of China.4
By the time Zheng He’s fleet visited in 1434, Europeans had silkworms and knew how to wind silk thread and to make silk cloth, but in small quantities. The illustrations and descriptions in the Nung Shu showed how the whole Chinese process—production of silk thread, the dyeing and weaving of fine silk cloth, winding the silk threads onto bobbins—could be coupled with water power to expand production enormously.
Inventions such as Chinese water-powered threshers and mills facilitated the mass production of silk and rice.
Figures tell the story: In 1418, Venetian merchants paid tax on a mere three hundred pounds of silk. In 1441, the Florentine government passed a law requiring farmers to plant between 5 and 50 mulberry trees per hectare, depending on the yield from their farms.5 Tens of thousands of mulberry trees were planted in northern Italy between 1465 and 1474. This period coincided with (or was one of the reasons for) a reversal of Venetian foreign policy. After the death of Doge Mocenigo in 1424, Venice under Francesco Foscari decided to become a land power in northern Italy. Verona, Vicenza, and the Po wetlands came into the Pax Venetica and the northern Po area was planted with thousands upon thousands of mulberry trees as well as rice (described in chapter 18).
The daily chores of a Chinese housewife.
The first Italian hydraulic silk mill, in Verona, is described in 1456. It is a Chinese machine. John Hobson in The Eastern Origins of Western Civilisation summarizes the spread of Italian silk-weaving machines to northern Europe: “The invention of the silk filatures (reeling machines) had been made in China in 1090. The Chinese machines comprised a treadle operated si
lk-reeling frame with a ramping board and a roller system. The Italian model resembled the Chinese right down to the smallest detail such as the lever joined to the crank. And significantly the Italian machines more or less replicated the Chinese right down to the eighteenth century.”6 As Hobson points out, the great British mills set up by John Lombe were copies of “Chinese”-designed silk mills in Italy. Lombe’s machines became the blueprint for the British cotton industry, whose products later swamped the world.
The combination of abundant mulberry leaves and mechanical reeling and weaving machines led to soaring silk production in Florence and Venice. The Italian mulberry was much more prolific than the Chinese. Florence manufacturing switched from wool to silk. Sericulture spread from Tuscany first to the Po Valley and then to the “terra firma” north of Venice. Alberti wrote there were “so many mulberry trees to feed the worms from which the silk is obtained that it is a marvellous thing.” Estimated production of raw silk in the Verona district rose from 20,000 light pounds in 1530 to 150,000 in 1608. Vicenza produced 60,000 light pounds in 1504 and double that amount by 1608. As printing got under way in Venice, publications in clear and simple language explained how best to tend mulberry trees and feed and care for silkworms. Titles such as Il vermicella dalla seta (The little silkworm) were remarkably similar to fourteenth-century Chinese books on sericulture.
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