(To see the illustrations, please click on theicons. Images open in new, smaller windows.)

In fact, “predictive competitions” between Chinese, Muslim, and European systems were organized by Chinese authorities during the early 17th century to uncover which methods gave the most consistently correct results. By 1645 Jesuit success in these “competitions” led to widespread reform and modification of traditional Chinese methods, such as the promulgation in the same year of the Shixian li, a calendar based on the computations published by the Bavarian Jesuit Johann Adam Schall von Bell in his Xinfa suanshu. Despite conservative opposition, Western stellar mathematics became the basis for Imperial astronomical calculations, and began a tradition of appointing Jesuits such as Schall and Ferdinand Verbiest to head the Imperial Bureau of Astronomy. [SLIDE 8: Verbiest’s prediction of solar eclipse April 29, 1669]

Jesuit importation of European scientific techniques not only contributed to the revision of Chinese methods, but it also stimulated Chinese scholars to look to their own scientific tradition, and to tackle the difficult task of reconstructing ancient mathematical works and scientific apparatus described in the historical record. New interest in Han and Song era technology in particular resulted in reconstructions of armillaries, sighting tubes, clocks, clepsydras, transmissions, and automata of various types. [SLIDE 9: Su Hong’s astronomical clock, ca. 1088] For example, the works of Guo Shoujing, a Yuan dynasty astronomer, mathematician, and engineer were reexamined. Guo was also a hydrographer, in charge of irrigation and watercourse regulation, but also developed a new calendar and designed astronomical instruments. As Lauren Arnold pointed out, the Mongols admired technicians and craftsmen wherever they came from, and scientists like Guo benefited from contact with Islamic scholars from Persia in his work. Unfortunately the lesson that there had often been external influences on Chinese technology was lost. Many scholars produced works with the idea that ancient Chinese inventiveness not only prefigured later European modifications, but actually that European science was in fact based on Chinese discoveries. The Qianlong Emperor himself says as much in his letters, believing that Western methods merely reflected refinement of earlier Chinese techniques.

Among the tasks assigned the Jesuits was the manufacture of new astronomical instruments for the Imperial Observatory. Under the direction of Adam Schall [SLIDE 10: Adam Schall] and Ferdinand Verbiest, [SLIDE 11: Ricci, Schall, Verbiest, ca. 1749] the palace workshops produced bronze instruments modeled on the designs of the Danish astronomer, Tycho Brahe, which he described in his book Astronomiæ instauratæ mechanica, published in 1598. In 1670 the Flemish Jesuit missionary in China, Ferdinand Verbiest, was given charge of the Imperial Observatory in Beijing and set about re-equipping it with a new set of instruments. He chose Tycho as his model and the Mechanica as his text, building an observatory on the Tychonic model. Some were improvements or modifications of existing instruments. In this era, just before the widespread use of telescopes for astronomy, these instruments, through which the stars and planets could be observed and by which distances and ascensions could be measured, had reached a high degree of sophistication. [SLIDE 12: Beijing Observatory]

There are three major types of instruments at the Beijing Observatory:
1. Quadrants and sextants used for determining altitudes and azimuths;
2. Armillary instruments for measuring right ascensions and declinations, or longitudes and latitudes with respect to the ecliptic;
3. Instruments designed for the determination of angular distances between celestial bodies (sextants and the bipartite arc).

Thus today in Beijing are to be found replicas of the instruments of Uraniborg [SLIDE 13: Beijing Observatory], refashioned in China and modeled directly on the Tychonic precedent but with Chinese adaptation and decoration. (All of Tycho Brahe's instruments are lost, most destroyed during the uprisings in Prague in 1619. The great globe ended up at the Round Tower in Copenhagen, where it was destroyed in the fire of 1728.)

Brahe’s exceptionally accurate data represented a major achievement in astronomical science It was on the basis of Brahe's observations that Johannes Kepler determined the laws of planetary motion and from these laws Newton derived the law of gravity. Not until the invention and diffusion of the telescope some years after Brahe's death was it possible to get more accurate readings. The Beijing Observatory still holds some surprises: Verbiest built two armillary spheres, [SLIDE 14: Armillary] instruments tested but deemed unreliable by Tycho, plus a zodiacal armillary, among the most complex and impractical of instruments for measurement, which traces its origins to the Islamic methods of Ptolemy's Almagest. [SLIDE 15: Verbiest clockworks armillary 1669; Prof. Rule will comment on the peculiar fascination with clocks in his talk]

Like the Jesuits in Beijing, Tycho was careful to raise his work above mere worldly concerns. In a passage that might have been uttered by a Confucian, Tycho links nobility with astronomy itself. He wrote in the Mechanica that: “the person who cultivates divine Astronomy ought not to be influenced by ignorant judgments, but rather look upon them from his elevated position, considering the cultivation of his studies the most precious of all things, and remaining indifferent to the coarseness of others. And when statesmen or others bother him too much, then he should leave with his possessions.”

Two Technical Curiosities
[SLIDE 16: Calculating Machine #141816] In 1962 and 1978, two historians of mathematics, Profs. Bai Shangshu and Li Di discovered a total of ten calculating machines among the storage-rooms at the Palace Museum in Beijing. Calculating machines are, of course, the predecessors of the 19th century Babbage calculating engines, and thus, the precursors of modern computers. Preliminary research indicated that these devices were designed and manufactured during the reign of Kangxi by the Manufactures Bureau. There has been much debate on just who made these machines and how they came to be constructed. The machine on display was first thought to be a Pascal calculator of French or Flemish design; it is similar in layout, and uses a peculiar romanization scheme for each calculating armature and Arabic numerals for readout. When this machine was shown in Brussels in 1989, it was thought possible it was a modification of a Christian Huygens design of 1659. However, the wheels denote a system of weights in Chinese measure, with auxiliary disk wheels, and the Neper’s Rods are in Chinese; a handle is inserted into the selected wheel, and addition, subtraction, multiplication, and division are possible; thus some guess it to be a variant of Schickard’s machines or a Leibniz type. Exactly who designed and built this particular calculating engine remains a mystery.

Finally, I wonder who would guess that the oldest precursor of the automobile might have been invented in China? Members of the Society of Automotive Engineers believe so. In the early 1670’s, Ferdinand Verbiest, during his tenure as head of the Astronomical Bureau in Beijing built a small working model of a steam turbine-powered vehicle which he demonstrated at the Court, and is widely considered as perhaps the oldest self-powered, wheeled vehicle. Verbiest appears to have based this now lost vehicle on an aeoliopile described in Giovanni Branca’s Le Machine of 1629; he writes about it in his 1674 treatise Astronomia Europaea in the section Pnematica.

The examples presented today are but a fraction of the many aspects of the Sino-Jesuit technological interchange. In addition to these more glamorous studies, basic technologies in fields such as optics, hydraulics, medicine, architecture, and agriculture were explored. The Jesuits and their Chinese associates studied phonetics and linguistics, created dictionaries, recorded dialects, and studied the technology of language. In spite of all the cultural misunderstandings, incorrect assumptions, and outright disasters that can happen when two cultures engage, at the level of the “mechanic” there seemed to always be craftsmen from both cultures who could cleverly work metal, delicately cast bronze, make screws and gears, pumps and transmissions, print complex mathematical books, or otherwise perform the task of Heavens Mechanics. To my mind, the fact that these skills were learned and lost and learned again makes the meeting of the “great mechanics” even more remarkable.