1434 (13 page)

R
elations between China and the West began long before 1434.
The Catholic Encyclopedia
presents a concise summary:

Tai Peng Wang kindly provided Chinese descriptions of papal envoys.
²
The ambassador who reached Florence in 1434 was by no means the first. According to Yu Lizi, Yuan China called the Papal States “the country of Farang” and the Papal States as a whole “Fulin” or “Farang.”
³
The official Ming history states that diplomatic exchanges between the Papal States and Ming China began as early as 1371, when Hong Wu, Zhu Di's father, assigned a foreigner from Fulin or Farang called Nei
Kulan (Nicholas?) as the Chinese ambassador to the Papal States to inform the pope of the dynastic change in China. Later on, Hong Wu appointed a delegation led by Pula (Paul?), who brought gifts and tribute to Farang.

After 1371, diplomacy between China and Europe was a two-way street, with the Papal States and China exchanging ambassadors. Yan Congjian in volume 11 of the
Shuyu Zhouzi Lu
described the visit of the Chinese ambassador to the Papal States in the reign of Zhu Di.

Yan Congjian starts by commenting that Italy's climate was rather cold, then continues:

Yan Congjian's descriptions are reflected in a Pinturicchio fresco of Aeneas Sylvius Piccolomini, the future Pope Pius II.
⁵
Born in 1405 to a distinguished Sienese family, Aeneas was educated at the universities
of Siena and Florence. Between 1431 and 1445, he opposed Eugenius IV. In 1445 he suddenly changed sides. He took orders in 1456, became a bishop in 1450 and a cardinal in 1456, and was named pope upon the death of Calixtus III in 1458.

Pinturicchio paints Pius II being carried on a throne into the Basilica of Saint John Lateran, Rome (where Pisanello was also sketching). The pope wears a red-lined cloak, and his hat is wrapped with golden thread. Before him are his cardinals in green, beige, pink, and blue, their heads covered in white tricorn hats. (See colour insert 3.)

A Ming dynasty book,
Profiles of Foreign Countries,
attests to continued diplomatic exchanges between Ming China and the Catholic Church in Italy.
⁶
This Chinese primary source includes “Lumi” among the foreign nations that paid China an official visit and rendered tribute during Zhu Di's reign (1403–1424). Lumi is Rome. The name is derived from Lumei, which is what the Song author Zhao Ruqua (1170–1228) called Rome. In his 1225 book
Zhufan Zhi
(Description of various barbarians), Zhao wrote that “all men are wearing turbans as their headwear. In winter they will be wearing coloured fur or leather coats to keep warm. One of their staple foods is the dish of spaghetti with a sauce of meat. They too have silver and gold currencies used as money. There are forty thousand weaver households in the country living on weaving brocades.”
⁷
Clearly, the Chinese were not strangers to the Papal States.

Now for some detective work to see what Pope Eugenius IV, Toscanelli, and his friends Regiomontanus, Alberti, and Nicholas of Cusa learned from Zheng He's delegate besides obtaining world maps.

After the Chinese ambassador had presented his power of attorney (represented by the brass medallion described in chapter 2) to Eugenius IV, he would have formally presented the Xuan De astronomical calendar, which would have established the precise date of the inauguration of the emperor—“when everything would start anew.”

Zheng He and the fleet had spent two years preparing to leave China and nearly three years reaching Florence. By the time they arrived in 1434 at the court of Eugenius IV, it had been nine years since
the emperor's inauguration. Foreign rulers also had to know the date of the emperor's birth, which was calculated from conception. In the case of Zhu Zhanji, this would have been 1398. So the calendar had to go back thirty-six years. To certify that the emperor had continued to hold the mandate of heaven during that period, the calendar would also need to show that the prediction of solar and lunar eclipses, comets, positions of planets and stars and untoward lunar conjunctions (the moon with Mercury) had been accurate throughout those thirty-six years—thousands of pieces of astronomical data had to be included.

One of Pisanello's sketches showing a Mongol face.

However, the calendar also had to predict the future. This required that it contain astronomical calculations of the accurate positions of sun and moon, tables of the five planets, the positions of stars and comets, dates of solstices and equinoxes, and a method of adapting those dates and times to the latitude of Florence. We know from the
Yuan Shi-lu,
the official history of Yuan dynasty, that this astronomical data was included in the
Shoushi
calendar, and one can see a copy of the 1408
calendar in the Pepys Museum in Cambridge, England. Two pages are shown on our
1434
website.

When the Chinese visited Florence in 1434, Toscanelli was in his prime, thirty-seven years old. Since graduating from university twenty years earlier, he had worked with Brunelleschi, a mathematical genius, and other leading intellectuals of the day. In particular, Toscanelli and Brunelleschi had, for the previous thirteen years, been collaborating on the complex spherical trigonometry required to build Florence's great dome over Santa Maria del Fiore. Toscanelli thus had ample opportunity to observe and accurately map the heavens in detail before the Chinese visit, but neither he nor any other of his circle did so. Toscanelli was a secretive bachelor who lived with his parents until they died, after which he lived with his brother's family. Although he never cited a particular influence or source for the prodigious mathematical and astronomical skills he displayed after 1434, he did bequeath a considerable collection of books, research papers, astronomical instruments, and world maps to his monastery. All but one of these have disappeared. Aside from that one remaining record—a manuscript housed at the Biblioteca Nazionale Centrale in Florence—we are left primarily with admiring references to him in letters among his friends. But we do know a bit about his actions. Did he behave differently after 1434? If so, how?

Jane Jervis, in “Toscanelli's Cometary Observations: Some New Evidence”
⁸
examined Toscanelli's surviving manuscript, a collection of folios. She compared the writing on the folios with that on the letters from Toscanelli to Columbus and Canon Martins and concluded that all but three of the folios were written by Toscanelli. Jervis then compared Toscanelli's study of two comets—one in 1433, before the Chinese visit, and another in 1456, after the visit. Folios 246 and 248 describe the 1433 comet; folios 246, 252, and 257 describe the 1456 comet.

The first comet pass was on Sunday, October 4, 1433, in the first hour of the night. Toscanelli's observations consist of a freehand drawing. He did not align the comet's positions with any stars or planets. No times are listed, nor are right ascensions or declinations of the stars or comets.

This is in stark contrast with Toscanelli's treatment, twenty-three years later, of the 1456 comet. Folios 246r and v, 252, and 257 contain a wealth of evidence. For the 1456 comet, he uses a Jacob's staff to give the comet's altitude (declination) and longitude (right ascension) to within ten minutes of arc.
⁹
Times are now given, as are the declination and right ascensions of the stars (Chinese methods). To achieve this radical improvement in technique, Toscanelli must have had a clock, an accurate measuring device, astronomical tables, and an instrument to show the position of the comet relative to stars and planets.

If true, James Beck's deduction that Alberti was assisted by Toscanelli in drawing the precise positions of stars, moon, and sun at noon on July 6, 1439 on the dome in the Sacristy of San Lorenzo similarly suggests a great leap in Toscanelli's scientific capabilities. For many years prior to 1434, Toscanelli had the opportunity to use the dome of Santa Maria del Fiore for astronomical observations. Yet he never did.

By 1475, Toscanelli had adopted a Chinese type of camera obscura, a slit of light and a bronzina (bronze casting), which he inserted in the lantern of the dome of the Florence cathedral. The pinhole camera has several advantages when measuring objects illuminated by the sun. The edges of the circle receive less exposure than the center. Since the focal length of an object's edges is greater than that of its center, the center is “zoomed in.” Shadows cast by the sun, or vision of the sun itself, thus appear sharper, thinner, and clearer.

By the early Ming dynasty, Zheng He's astronomers had refined this camera obscura and used it in conjunction with an improved gnomon to enable measurement of the middle of the shadow of the sun within one-hundredth of an inch. Toscanelli used the Chinese method in a most ingenious way, adapting the dome of Santa Maria de Fiore as a solar observatory.

Between May 20 and July 20 the sun at noon shines through the windows of the lantern on the top of the dome. Toscanelli had the lantern windows covered in fabric with a small slit to allow sunlight through at noon. After passing through the slit, the sunlight became a beam. A bronzina was positioned so that the beam landed on it, and in
the center of the bronzina was a hole. As the beam struck the bronzina, the hole would channel it down to the marble floor three hundred feet below. On the floor, Toscanelli drew a north-south meridian line, with incisions to note the position of the sun at the summer solstice. Regiomontanus said that using the meridian line, Toscanelli could measure the sun's altitude (and hence declination) to within two seconds of arc.

In 1754 a Sicilian Jesuit priest, Leonardo Ximénes, experimented with Toscanelli's instrument. Ximenes compared data from the solstices in Toscanelli's era to his own measurements of 1756. He found that Toscanelli was able to determine not only the height of the sun at the summer solstice but also the change in height over the years, which resulted from the change in the shape of the earth's elliptical passage around the sun.

The minute differences in the sun's altitude from one year to another preoccupied Regiomontanus as well, as he said:

What is so important to Toscanelli and Regiomontanus about the precise declination of the sun? When I first joined the Royal Navy in 1953, sailors trooped to the Far East by passenger liner rather than by aircraft. Each day at noon, the ship's navigator, captain, and officer of the watch would march resplendent in white uniforms on to the open bridge and stand side by side looking at the sun. Shortly before noon they would start taking the altitude of the sun with their sextants. Just before it was at its highest they would cry, “Now! now! now!” Upon the final
Now!
they would read out the sun's maximum altitude taken from their sextants. They would then declare the distance traveled from the previous noon. The lucky sweepstakes winner would be
announced over the ship's address system and would be expected to buy drinks all around.