Authors: Gavin Menzies
1434 (20 page)
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 1429â1433. 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 Taccolaâas 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 copiesâ¦. The drawings are obviously modeled on Taccola but Francesco often adds or omits details and in some cases introduces significant changesâ¦. Other people's ideas and procedures were shamelessly plundered even by artists like Francescoâ¦. [He] never mentioned the name of his source in the works he later authored. (p 36)
From theâ¦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 systemsâ¦. 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'sâ¦. 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 âmachine complex' or âgear 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 âin 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 outâhe 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 copyâit 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 yearsâ¦.
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 Shu
16
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 Taccola
17
and di Giorgio
18
had depicted. With feverish excitement I turned the pagesâit 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 machinesâ¦. 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