Then I had a stroke of luck. While on holiday in Toledo in 2005, Marcella and I happened upon a wonderful exhibition about Leonardo da Vinci. It was here that I was first introduced to the great works of Francesco di Giorgio Martini and the profound influence that these had on Leonardo.
In my ignorance, I had never heard of Francesco di Giorgio. Yet it was obvious that he was important; he had taught Leonardo about waterways. I decided to find out more on our return to London.
In the wonderful British Library I found first that Francesco seemed to have invented the parachute before Leonardo. For what follows I am indebted to Lynn White, Jr., author of “The Invention of the Parachute” in Technology and Culture. Dr. White wrote:
The first known European parachute has been that sketched by Leonardo in the Codex Atlanticus on Folio 381v, that Carlo Pedretti dates circa 1485…. However, British Museum Additional Manuscript 34113, folio 200v. shows a parachute which may be in a somewhat independent tradition since it is conical.
This rich and massive volume [in the British Library] seems to have been unnoticed by historians of technology. Can it be dated and placed?
The Manuscript , a quarto of 261 folios of paper, was purchased by the British Museum in 1891…. Folios 21r. to 250v. [are] a treatise on mechanics, hydraulics, etc. with a multitude of drawings….
Folios 22r. to 53v. are nearly identical in content and sequence with Florence, Biblioteca Nazionale Manuscript Palatinum 766, an autograph of the famous Sienese engineer Mariano detto il Taccola (who died in the 1450’s), that was dated by him (on folio 45v) to 19 Jan. 1433. Most of the remaining material in British Museum Additional Manuscript 34113 as far as folio 250v. [the parachute drawings are in folio 200v. and 189v.] is the sort of thing we have come to associate with manuscripts long credited to Francesco di Giorgio of Siena (1439–1501). Indeed folio 129r. [before parachute drawings] is entitled “Della providentia della chuerra sicondo Maestro Francesco da Siena,” and on folio 194v. [after parachute drawing], next to the picture of a large file, is written “Lima sorda sichondo il detto Maestro Francesco di Giorgio da Siena.”1
Dr. White analyzed the watermarks of the paper on which the parachute drawings appear. He concluded:
Probably drawn by di Giorgio, this parachute differs in shape from that of Leonardo’s.
Consequently the drawing on folio 200v. [parachute] may be placed reasonably in the 1470’s or not much later, if we are to believe the watermarks….
Our new parachute is, therefore, at the latest, contemporary with and probably slightly earlier than that of Leonardo…. It is indicative of Leonardo’s perceptiveness that he picked up this idea so quickly and that he began to make it more sophisticated.
So it seems Leonardo learned not only about canals and aqueducts from Francesco di Giorgio but also about parachutes. What else? Back to the British Library!
Dr. Ladislao Reti, an expert on Leonardo, has this to say about Francesco di Giorgio Martini’s “Treatise on Engineering and Its Plagiarists”:
Francesco di Giorgio Martini (1439–1501) the great Sienese painter, sculptor and architect, was also interested as were several of his contemporary fellow craftsmen, in the study and development of mechanical devices. This was in accordance with the still flourishing Vitruvian tradition. His engineering treatise, still little known, is mainly dedicated to civil and military architecture and contains hundred of small but perfectly drawn illustrations showing war machines of every kind, as well as cranes, mills, pumps etc…. Although a number of studies have been published about the artistic and architectural work of Francesco di Giorgio, his work in technology has only occasionally been noticed.2
Dr. Reti then lists the libraries and museums in which Francesco’s Trattato di architettura civile e militare is held and continued:3
There is also an incomplete manuscript3 that once belonged to Leonardo da Vinci. This latter is of particular interest because Leonardo added marginal notes and sketches; the manuscript is now in the Laurenziana Library in Florence (Codex Mediceo Laurenziano 361 formerly Ashb.361 ). In addition several old copies of the treatise or its drawings are to be found in other Italian libraries, reflecting the early interest aroused by Francesco’s work.
These Trattato manuscripts, especially those parts dealing with mechanical engineering and technology, have never been adequately studied or fully published. A fairly accurate picture of Francesco di Giorgio Martini’s work was first made available to scholars in 1841 when Carlo Promis, using the Codex owned by Saluzzo, published the Trattato for the first time (Trattato di Architettura Civile e Militare edited by Carlo Promis (2 vol., Turin, 1841)….
Further confusion was caused by the fact that the Codex Saluzziano [quoted above] and the Codex Laurenziano [the one owned by Leonardo da Vinci] in spite of being written by the same hand, and containing almost identical drawings, were, for a long time, not attributed to the same author [Francesco di Giorgio]. Early interest was aroused by the Laurenziana Codex because of the marginalia added by Leonardo.
Dr. Reti then lists the contents of the Trattato:
In these folios we can identify no less than 50 different types of flour and roller mills including horizontal windmills…sawmills, pile drivers, weight transporting machines, as well as all kinds of winches and cranes; roller-bearings and antifriction devices; mechanical cars…a great number of pumps and water lifting devices…. and an extremely interesting water or mud-lifting machine that must be characterized as the prototype of the centrifugal pump…. [Francesco] described original war machines offensive and defensive, including the hydraulic recoil system for guns. There are also devices for diving and swimming almost identical with those drawn by Leonardo da Vinci in his Manuscript B.
Comparisons of Francesco di Giorgio’s and Leonardo’s machines are available on our 1434 website.
Leonardo’s Helicopter and Parachutes
Apart from copying di Giorgio’s parachute, Leonardo’s helicopter was not original. His proposed helicopter is shown on the cover of this book. In “Helicopters and Whirligigs,” Dr. Reti argues that a model helicopter in the form of a children’s whirligig toy appeared in Italy circa 1440 from China and provided the theoretical basis for Leonardo’s famous helicopter project.4
Dr. Reti contends that it was first drawn in 1438 in the Munich manuscript of Mariano Taccola (see 1434 website).
Clearly, Francesco di Giorgio was an astonishingly innovative designer and engineer. His Trattato di architettura still exists in several versions. Marcella and I have examined the copy in Florence once owned and annotated by Leonardo. We were astounded by the range of his drawings; it seemed to us that Leonardo was a consummate three-dimensional draftsman who had taken Francesco’s drawings of his machines and made even better drawings of them. Leonardo’s role, in our eyes, was changed; he was a superb illustrator rather than the inventor. For as far as we could see, almost all of his machines had been previously invented by Francesco di Giorgio.
This was quite a shock. We decided to unwind in a nearby mountain village, Colle val d’Elsa,5 the birthplace of Arnolfo di Cambio, the genius who designed Renaissance Florence. His home was once the palace of silk merchants, the Salvestrinis. Today it is a hotel where we had the good fortune to stay in a room with walls three feet thick, which had once been Arnolfo’s bedroom. We had a view of a classic Tuscan valley—the hills rolling away like long green ocean swells; the crests of the waves; the stone farmhouses surrounded by vineyards and olive groves. The crowing of cockerels, the bray of a donkey, and the laughter of distant unseen children floated across the sunlit land. We had a panoramic view of the valley far below. Around us huddled the town in which Arnolfo grew up—a mass of fortified towers within the protection of sturdy stone walls, a veritable fortress.
We had dinner al fresco in the square, the walls and flagstone floor still pulsating with heat. After a splendid bottle of Dolcetto, a dark red, dry, sparkling wine, we asked local people what they knew of Francesco di Giorgio. He appeared to be as famous as Leonardo or Mariano Taccola. This was another surprise—who was Mariano Taccola, known as “the Crow” or “the Jackdaw”? Was he called Jackdaw because of his beak or because he “jackdawed” the work of others?
At dawn, we left for Siena and Florence to view Taccola’s drawings. The trip yielded another bombshell: Taccola seemed to have invented everything that Francesco di Giorgio later drew; di Giorgio had obviously copied Taccola.
Mariano di Jacopo ditto Taccola was christened in Siena, near Florence, on February 4, 1382.6 His father was a wine dealer. His sister Francesca had married into the comfortable family of a silk trader.
Siena7 had been built on a hill for protection. The land beneath was swamp. Obtaining clean fresh water and draining the swamps were constant necessities. Hence it was natural for a well-educated young man to be acquainted with aqueducts, fountains, water mains, and pumps, as well as the medieval weapons deployed to protect the town—trebuchets and the like.
A prosperous town threatened by Rome from the south and Florence from the north, Siena was a “free city” of the Holy Roman Empire, but Sigismund, the emperor,8 was too weak to protect her. (In Taccola’s time the emperor was preoccupied with the Hussite wars.)
In 1408, Taccola married Madonna Nanna, the daughter of a leather merchant, which enabled him to move up the social scale. In 1410, he was nominated for entry into the Sienese Guild of Judges and Notaries, where his apprenticeship lasted six or seven years. He seemed to have had a penchant for failing his exams. In 1424, Taccola became secretary of a prestigious charitable institution, the Casa di Misericordia, an appointment he held for ten years. As such, he would have become acquainted with influential visitors to Siena—such as Pope Eugenius IV, Giovanni Battisa Alberti (in 1443), and the Florentines Brunellschi and Toscanelli.
In 1427, Taccola began to keep technical notebooks, containing knowledge he had acquired “with long labour.” As Prager and Scaglia explain, Taccola’s early entries in his notebook are about the defense of Siena and the operation of harbors.9
Between 1430 and his death in 1454, Taccola produced a series of amazing drawings that were published in two volumes, De ingeneis10 (Of four books) and De machinis,11 and an addendum. The range of his subjects is quite extraordinary. Book 1 of De ingeneis contains harbors, bucket pumps, mounted gunners, bellows for furnaces, underwater divers, fulling mills, and siphons. Book 2 features cisterns, piston pumps, dragons, amphibious machines with soldiers, and ox-powered gin mills. Book 3 includes chain pumps, tide mills, variable-speed hoists, winches, quarrying machines, flotation machines to recover sunken columns, builders’ cranes, mechanical ladders, sailing carts, and amphibious vehicles. In Book 4 he tackles trigonometrical surveying, tunneling, machines for extracting posts, treasure-hunting tools, windmills and watermills, pictures of monkeys, camels, and elephants, trebuchets, armored ships, paddle boats, roof-beam joists, and reflective mirrors. De ingeneis was followed (ca. 1438) by De machinis, a volume of drawings of mostly military machines (described in chapter 19).
An articulated siege ladder as featured in the general collection of Chinese Classics of Science and Technology.
Taccola’s articulated siege ladder is one of many military inventions that bear a striking resemblance to Chinese versions.
Prager and Scaglia describe Taccola as a pivotal figure in the development of European technology. In their view, Taccola ensured that the long stagnation of many technical practices of the Middle Ages came to an end. His De ingeneis became the starting point for a long line of copybooks.
So how did a clerk of works of a small mountain town suddenly produce books of drawings of such a huge range of inventions, including a helicopter and military machines that were at that time unknown in Siena?
We could profitably start with the dates of Taccola’s books. Prager and Scaglia, in my opinion the leading authorities on Taccola, put publication of books 1 and 2 of his De ingeneis at around 1429–1433. Taccola began books 3 and 4 around 1434 or 1438 and continued working on them until his death in 1454; De machinis was begun after 1438 and the addenda drawings around 1435.
According to Prager and Scaglia, the addenda drawings, which were inserted in all four books after about 1435, represent a significant change for Taccola. The new technique is very characteristic of soldiers and engines in small scale, the sketches inserted and annotated with small handwriting in the last two books and in the sequel. Sketches of engines, mainly military in function, may be seen on almost all pages of books 1 and 2; they always surround primary drawings, often in copious array. This paragraph seems to me to mean that another author (Francesco di Giorgio) had begun to annotate Taccola’s drawings in books 1 and 2.
Taccola’s drawings were certainly added to by Francesco after 1435. In his marvelous book The Art of Invention: Leonardo and the Renaissance Engineers, Paolo Galluzzi writes:
The final pages of Taccola’s autograph manuscripts De Ingeneis I-II carries a series of notes and drawings in the hand of Francesco di Giorgio (fig. 26). No document better expresses the continuity of the Sienese tradition of engineering studies. They offer us a snapshot, so to speak, of the actual moment when the heritage was passed on from Taccola to Francesco di-Giorgio.11
A reproduction of this snapshot of history is shown by kind permission of the Istituto e Museo di Storia della Scienza, Florence, on our 1434 website. So we can say at this stage Leonardo had di Giorgio’s book of Machines, which were adaptations of Taccola’s drawings.
Francesco di Giorgio Pillages Taccola’s Work
Di Giorgio was a wholesale plagiarizer. Here are eight examples of his pillaging of Taccola’s work, which he never acknowledged.
Francesco’s picture of a collapsing tower is almost identical to Taccola’s; Francesco similarly copies Taccola’s underwater swimmers and floating riders on horseback (see the 1434 website).
Chinese water-powered vertical and horizontal rice grinding mills.
Di Giorgio’s design shows a similar method of converting vertical energy to horizontal.
Francesco, whose drawings were made after Taccola’s, employs the same distinctive trebuchet as Taccola. His hoists and mills, which transform vertical power to horizontal, and paddle-wheel boats copy Taccola’s, as do his devices for measuring distances, his weight-driven wheels, and his ox-drawn pumps. Several examples are shown on our 1434 website.
Francesco di Giorgio Improves on Taccola
Francesco was a very good draftsman. He improved on Taccola—as can be seen in almost every drawing shown. Furthermore, he adds details to improve the quality of the illustration. Galluzzi writes:12
Many of the 1,200 odd drawings and practically all the notes [of di Giorgio’s Codicetto] are in fact derived from Taccola’s manuscripts. But hardly any of the drawings or notes are slavish copies…. The drawings are obviously modeled on Taccola but Francesco often adds or omits details and in some cases introduces significant changes…. Other people’s ideas and procedures were shamelessly plundered even by artists like Francesco…. [He] never mentioned the name of his source in the works he later authored. (p 36)
From the…small manuscript [Codicetto] onward, in the series of drawings and notes based on Taccola’s manuscripts, we find an increasingly frequent recurrence of devices not dealt with by Taccola. The drawings are carefully drafted without annotations and clearly focus on four topics: machines for shifting and lifting weights, devices for raising water, mills and wagons with complex transmission systems…. There is something illogical and incomprehensible about the abrupt switches between the series of faithful reproductions from Taccola and the presentation of a multitude of innovative projects. For these are not only “new” machines but devices of far more advanced mechanical design than Taccola’s…. his devices feature complex gear mechanisms whose careful and highly varied arrangements are calculated to transmit to any level and at any desired velocity the motion produced by any source. As we know of no precedents that could have inspired Francesco, we are led to assume that they are his original contribution.13
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 .
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 lifting 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
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.