medieval science instrument

Professor Derk Bodde wrote: “The Chinese were also pioneers in the ancient art of alchemy which antedated modern chemistry. This field of experimentation, which concerned itself with efforts to convert base metals into precious ores, attracted the attention of men until the eighteenth century, when its theories were exploded. We are all familiar with the romance which surrounded the lives of Roger Bacon and the other notable European alchemists of the late Middle Ages and the Renaissance. Who has not seen pictures of them laboring over their smoky furnaces in secret laboratories, vainly trying to produce artificial gold or silver from such base metals as lead and mercury?...Yet, despite the mystical practices that undoubtedly entered their work, modern historians recognize that these men were often much more than ordinary quacks. Some, indeed, ranked among the most learned scholars of their time. The thirteenth century Roger Bacon, for example, is regarded as one of the fathers of modern science. Alchemy, indeed, as its very name shows, was in some ways the forerunner of our modern chemistry. /=/ [Source: Derk Bodde, Assistant Professor of Chinese, University of Pennsylvania, Asia for Educators, Columbia University, July 1948 /=/]

“The syllable "al," in the name "alchemy," tells us something about the history of the word. It shows us that it is of Arabic origin, as are several other words that have "al" as their first syllable, such as "alcohol," "algebra," or "alkali." ("Al" means "the" in Arabic.) But though the Arabs undoubtedly brought alchemy to Europe, they were not its originators. /=/

“Traditionally, alchemy is believed to have started in Alexandria and other Egyptian cities among metalworkers who lived there during the early centuries after Christ. These men, in their turn, are commonly believed to have followed philosophical ideas going back to the ancient Greeks. It is now established, however, that Chinese alchemy is more than two centuries older than that of the Alexandrians. Though it is not yet absolutely proved that Western alchemy had its origin in China, we do know that the world's earliest recorded attempt at alchemy appears in an official history of China in 133 B.C. /=/

Books and Sources on Chinese Inventions: "Science and Civilization in China" by Joseph Needham ; The Wikipedia article is very long and thorough Wikipedia ; Science and Civilization by Joseph Needham in China Series Needham Research Institute ; Chinese Inventions Timeline Columbia University ;

Ancient Chinese Alchemy

Professor Derk Bodde wrote: In 133 B.C. “a certain old man came before the emperor with the claim that at the age of seventy he had discovered a way to keep from growing older. When the emperor asked for the secret of this magic power, the old man told him that if he would worship the Goddess of the Kitchen Stove, he would find himself miraculously able to change a mercury-sulfur compound called "cinnabar" into gold. And by eating from plates made of this artificial gold, he could prolong his life indefinitely as he, the old man, had done. The emperor eagerly followed these instructions, but unfortunately for their success, the old man himself soon fell ill and died! [Source: Derk Bodde, Assistant Professor of Chinese, University of Pennsylvania, Asia for Educators, Columbia University, July 1948 /=/]

“Several other equally unsuccessful attempts are recorded in the official Chinese histories and in other literature during the next two centuries. It is not surprising, therefore, that much prejudice developed against would-be alchemists. Even the death penalty, in fact, seems to have been decreed for anyone convicted of trying to produce artificial gold. This severe punishment, however, did not stop the alchemists from secretly continuing their work, and around A.D. 150 a very important treatise on alchemy appeared. It contains the world's earliest detailed recipe for manufacturing artificial gold in order to produce the magic elixir of immortality. Its language, however, is purposely made so abstruse that no modern chemist would dare to follow its directions! Nevertheless, some of its symbolism, as when it speaks of mercury as "the tiger" and sulfur as "the dragon," is remarkably similar to that found later in European literature on alchemy. /=/

“Chinese alchemy was based on the theory that the fundamental law of the universe is one of change — in other words, that everything in the universe is constantly evolving from one state to another and nothing remains permanently the same. The transformation of one metal into another by human means, therefore, was regarded simply as a particular instance of the operation of this universal natural law. Gold was the chief metal that Chinese alchemists concentrated on producing. This was not because they were particularly desirous of wealth, but rather because they hoped to discover a means of preparing an elixir of immortality. Gold was regarded as the most suitable substance for their experimentation, as it does not rust or corrode under chemical action. They reasoned that it must, therefore, be an "immortal" mineral, which, if taken as a medicine by mortals, would endow them with similar immortality. /=/

Treatise on Chinese Alchemy from A.D. 325

medieval science instrument

A famous Chinese treatise on alchemy written by a recluse scholar, Ko Hung, around the year 325 reads: “Flying, running, and crawling creatures all have definite forms. Yet all of a sudden they may discard their old bodies and change into new creatures. Among all creatures, man is the noblest. Yet there are not a few cases when men and women have been changed into a crane, a stone, a tiger, a monkey, sand, or a turtle.... Transformation is the natural law of the universe. Why, then, should we suspect that gold and silver cannot be made out of other things?” /=/

But success, he warns, is possible only when working in solitude and after long spiritual preparation: “The preparation of the elixir should be done in some lonely spot on a famous mountain, with not more than three people present. One should first fast for one hundred days and wash oneself with the five fragrant things until one is perfectly purified. One should not approach any impure things or have contact with vulgar people. Furthermore, one should not allow doubters of the Art to know about the matter, for if any slander is made of the Divine Elixir, it will surely fail.” /=/

Having prepared oneself, one goes to work as follows: “Use an iron vessel, nine inches long and five inches in diameter. Fill it with a paste made of ground arsenic sulfide, mixed with powder made from worms, crickets, beetles, etc. Two measures of "elixir powder water" may be added. Place it over a fire of horse dung until it is extremely dry..." /=/

Several more processes of this kind are carried out, until “the furnace is heated to redness over a charcoal fire. Mercury is added. When the mercury begins to stir, lead is poured in. Yellowness will then rise up from the sides and meet in the middle. Upon pouring this on the ground, gold will be obtained...This gold is then mixed with two unidentifiable substances for a hundred days, until it becomes soft and can be kneaded into pills. The eating of these pills three times a day: will drive away all diseases. A blind man will regain his sight, a deaf man his hearing, and an aged man will become again as if he were but thirty years old. It will be possible to enter fire without being burned, and to be invulnerable to all evils, poisons, cold winds, hear, or dampness.” /=/

Differences Between Chinese Alchemy and Western Alchemy

medieval science instrument

Professor Derk Bodde wrote: “In these ideas Chinese alchemy shows important differences from the practices of the Alexandrian metallurgists, who never claimed to be able to make genuine gold and silver out of other metals. They merely said they could change the color of these other metals, and thus make them look like gold or silver. Furthermore, their aim in so doing was to gain wealth by palming off their imitations of precious metals on other people. They did not have the belief, as did the Chinese, that gold is an "immortal" metal, and that it could, therefore, be used to give immortality to human beings. [Source: Derk Bodde, Assistant Professor of Chinese, University of Pennsylvania, Asia for Educators, Columbia University, July 1948 /=/]

“This fundamental Chinese idea crops up again in later Arabic and European alchemy, though often mixed with other ideas that go back to the Alexandrians. Thus, in European alchemy we often see references to the "philosopher's stone," the "elixir of life," and the "fountain of perpetual youth." (It will be remembered that when the Spanish explorer, Ponce de León, discovered Florida in 1521, he was searching for such a "fountain of youth.") /=/

“By the thirteenth century, when alchemy was attracting attention in Europe, it had become largely discredited in China. Before that time, however, Chinese alchemists had succeeded in persuading even emperors to try their elixirs. Among them were some who actually died from the effects! What is more important is the fact that the experiments of the Chinese alchemists probably resulted in certain inventions of great practical value for mankind. Among them, it has been suggested, were porcelain and gunpowder. The use of gold in modern medicine, especially in treatment for arthritis, has still to be traced historically, however. /=/

“In Europe, alchemy lingered many centuries longer than in China. Its deathblow was dealt only in 1783, when Lavoisier (l743-94), the famous French father of modern chemistry, published an epoch-making treatise. In this he demonstrated, by making careful weight measurements of things before and after they had been burned, that fire cannot possibly exist as a separate element. He thus disproved the old theory that all things are formed from the constantly changing combinations of only a few basic elements, of which fire is one. In its place he laid the foundations for our modern classification of chemical elements. And our grandfathers came to consider alchemists quacks or magicians. <

“We have no definite evidence of how the Chinese art of alchemy was brought to Western Asia, but very probably it was carried there over the Central Asiatic trade route by traders, religious pilgrims, or possibly even soldiers. In the case of paper, for example, we know that the Arabs learned the secret of its manufacture from Chinese soldiers whom they captured in battle in the year 751. As Arabic alchemy begins not long after this event — in the ninth century — it, too, might very possibly have been learned by the Arabs from the Chinese through chance contacts of this sort.” /=/

Early Chinese Geography and Maps

Song Era Map

Chinese believed that the Earth was the center of universe long after Copernicus, and believed the world was flat until the 19th century. They also thought there was a massive body of water inside the earth from which all life sprung, and the universe was a "great vault of heavens" over the earth. Despite these beliefs, the Chinese developed a very reliable and accurate system of cartography. Early Chinese maps were made of silk and had a grid-like coordinate system. These maps showed mountain ranges, roads and rivers, and distinguished between towns, cities and villages.

Maps were described in Chinese texts written in 700 B.C. The oldest Chinese map yet found dates back to 200 B.C. Bureaucrats in the Chou Dynasty (1120-256 B.C.) made maps of feudal principalities and registered their populations. After China was unified in 221 B.C., maps were used to define the boundaries of different regions. The world's oldest map is a clay tablet with the Euphrates River and Mesopotamia. It dates back to 2250 B.C.

In A.D. 267 the famous Chinese mapmaker Phei Hsui wrote that maps should show: "mountains and lakes, the courses of rivers, the plateaus and plains, the slopes and marshes, the limits of the nine ancient provinces and the sixteen modern ones...commandeers and fiefs, prefectures and cities...and lastly, inserting the roads, paths and navigable rivers." Beginning in the Song dynasty (960-1279) north was regularly fixed at the top of all maps. The Chinese defined north, south, east and west from observations of the north star and the sun.

The Chinese system of coordinates may have evolved from the fact that the first Chinese maps were drawn on silk. The terms (ching and wei) which Phei Hsui used for coordinates on his maps were the same words that had long been used for the warp and the weft in the weaving of textiles. Some historians have theorized that the idea of a rectangular grid on a map was suggested by “following a warp and a waft thread to their meeting place?" [Source: "The Discoverers" by Daniel Boorstin]

The world's oldest known printed map is from China and dates to A.D. 1115. In A.D. 801, during the Tang dynasty (618 to 907), the Emperor's cartographer produced a one-inch to 33⅓-mile scale map of the entire Chinese empire that was 30 feet high and 33 feet high. This map has been lost to time. In 1136, a "map of Chinese and foreign lands" was cut into stone. It showed rivers and the Great Wall of China and had descriptions and histories of the places it named.

Early Chinese Astronomy

The Chinese have been recording celestial events for about 4500 years. Chinese astronomers were among the first to chart constellations and record supernovas. In 2296 B.C., Chinese astronomers observed a comet. The earliest written records of astronomical phenomena are inscriptions on Shang oracle bones from the 14th century B.C. with mentions of eclipses, solstices, seasonal stars, constellations and other phenomena.

In ancient Chinese astronomy 28 constellation were placed into four equal groups with each group under the protection of an animal deity: a blue dragon in the east, a white tiger in the west, a phoenix-like mythological bird in the south and turtle-snake hybrid in the south.

The Chinese developed a system of observation based on the equator and the poles that was not adopted by Europe until 4000 years later. In 352 B.C. they described a super nova that lit up the night time sky for ten days. Chinese records cover long periods for which no other accurate chronicle of celestial events exist and modern astronomers still refer to them in their study of novae and supernovas.

Ancient Chinese astronomers recorded an eclipse on September 24, 1912 B.C. that is the earliest verifiable eclipse reported by any people. In an ancient text the philosopher Mozi wrote: "The three Miao tribes were in disarray. Heaven ordered their destruction. The sun rose at night." Modern astronomers researching the event concluded that the eclipse indeed took place when the ancient Chinese said it did.

Using computer models which plot the courses of planets thousands of years in the past, scientists have discovered that on March 5, 1953 B.C. Mercury, Mars, Saturn, Jupiter and Venus were "lined up like a string of pearls" with the moon and sun. This date also happens to be the first day of the Chinese calendar when Emperor Yu became the first emperor of the Xia dynasty. [National Geographic Geographica, December 1993.]

20080212-early star map brrok.jpg
Early star map

Supernova Seen by Ancient Chinese Observers

The oldest recorded supernova was from A.D. 185: a "guest star" observed in ancient China for eight months before disappearing. In 2011 astronomers announced they had discovered they were witnessing a massive supernova 8,000 light-years away. New infrared observations from NASA’s Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) have revealed how the first supernova ever recorded occurred and how its shattered remains ultimately spread out to great distances.

In October 2011, AFP reported: “The findings show that the stellar explosion took place in a hollowed-out cavity, allowing material expelled by the star to travel much faster and farther than it would have otherwise. The Spitzer Telescope doesn't just spot supernovae, but also planetary collisions

"This supernova remnant got really big, really fast," said Brian Williams, an astronomer at North Carolina State University and lead author of a new study detailing the telescope's findings online in the Astrophysical Journal."It's two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we've been able to finally pinpoint the cause," he added.

In 185 A.D., Chinese astronomers noted a "guest star" that mysteriously appeared in the sky and stayed for about eight months. By the 1960s, scientists had determined that the mysterious object was the first documented supernova.Later, they pinpointed the object, known as RCW 86, as a supernova remnant located about 8,000 light-years away but remained puzzled at how the star's spherical remains were larger than expected. "With multiple observatories extending our senses in space, we can fully appreciate the remarkable physics behind this star's death throes, yet still be as in awe of the cosmos as the ancient astronomers," said Bill Danchi, Spitzer and WISE program scientist at NASA Headquarters in Washington.

Astronomy, Time and Astrology in China

20080212-ancient theory of solar system.gif
Ancient map of the solar system
In China, astrology did not evolve into the hard science of astronomy like it did n the West. Specific events in the cosmos were thought to have links to events on earth.

In the 16th century Italian priest Matteo Ricci noted that Chinese astronomers included 400 fainter stars on their celestial maps than Europeans did on theirs maps, "yet with all this, the Chinese astronomers take no pains whatever to reduce the phenomena of celestial bodies to the discipline of mathematics...they center their whole attention on that phase of astronomy which our scientists term astrology, which may be accounted for by the fact that they believe that everything happening on this terrestrial globe of ours depends upon the stars."

Time itself was viewed as a fabric rather than a linear sequence of events, with events in one place having impacts on other events regardless of their time and place. One scholar said that for Chinese the goal is “temporal harmony with in the person, among individuals and between society and nature.” Time was also seen as cyclical and political dynasties were seen as things that rose and fell in accordance with celestial cycles. Confucius called the North Star the "Great Imperial Ruler of Heaven.”

Imperial Astrologer in China

The Imperial astronomer was one of the highest ranking hereditary officials. He spent the night making observations from the emperor's observatory tower. According to once Chinese text, he "concerns himself with the twelve years [the sidereal revolutions of Jupiter], the twelve months, the twelve [double] hours, the ten days, and the positions of the 28 stars. He distinguishes them and orders them so he can make a general plan for the state of the heavens. He takes observations of the sun at the winter and summer solstices, and the moon at the spring and autumn equinoxes, in order to determine the succession of the four seasons." [Source: "The Discoverers" by Daniel Boorstin]

medieval star chart

The Imperial astrologer also "concerns himself with the stars in the heavens, keeping a record of the changes and movements of the planets, the sun and the moon, in order to examine the movements of the terrestrial world, with the objective of distinguishing good and bad fortune...All the fiefs and principalities are connected with distinct stars, and from this their prosperity or misfortune can be ascertained. He makes prognostications, according to the twelve years [of the Jupiter cycle], of good and evil in the terrestrial world. From the colors of the five clouds, he determines the coming of floods or drought, abundance or famine. from the twelve winds he draws conclusions about the state of harmony of heaven and earth, and takes note of the good or bad designs which result from accord or discord." [Source: "The Discoverers" by Daniel Boorstin]

One of the main functions of early Chinese clocks and the Imperial Astrologer was to help the Emperor schedule his sex life with his numerous wives and concubines. See Emperor’s Sex Life Under Court Life, Imperial China

The Emperor, Ricci wrote, "prohibited anyone from indulging in the study of this science unless he was chosen for it by hereditary right. The prohibition was based upon fear, lest he who should acquire the knowledge of the stars might become capable of disrupting the order of the empire and seek an opportunity to do so." [Source: "The Discoverers" by Daniel Boorstin]

Calendar Clocks in China

The Chinese invented the world's first mechanical clock in the Tang Dynasty (618 to 907), and then lost the technology over the centuries only to have it reintroduced by Europeans in the 16th century. The Chinese divided the day into temporary hours, which were determined by the amount of sunlight on a given day and varied with time of year. Sundials have been used in China at least since 2,600 B.C.

Early Chinese clocks recorded units of the Chinese calendar not hours and minutes. The establishment of a calendar was just as important to Chinese emperors as the royal minting of coins was in Europe. Private clock-making was a treasonous crime. Only authorized mathematicians and astronomers were allowed to produce and adjust the calendar; their methods were closely guarded secrets; and each new dynasty produced it own new calendar. Between the first unification of the Chinese empire in 221 B.C. and the end of the Qing dynasty in 1911 about one hundred different calendars were produced. [Source: "The Discoverers" by Daniel Boorstin]

Errors in the calendar clocks often resulted in disasters for farmers and undermined the authority of the emperor, which is one reason why the "Son of Heaven" kept his clock under a veil of secrecy. "Chinese farming depended on irrigation, and successful irrigation required predicting the rhythms of monsoon rains and the melting of the snows to flood the rivers and fill the canals." [Source: "The Discoverers" by Daniel Boorstin]

Water Clocks and Fire Clocks in China

20080212-fire clock.jpg
Fire clock

Water clocks have been used since ancient times to record and measure time in China and other places. They operate on the principle that water can be made to drip at a fairly constant rate from a bowl with a tiny hole in the bottom. The learned civil servant and clock maker Su Song wrote,"There have been many systems and designs for astronomical instruments during past dynasties, but the principal of the use of water-power for the driving mechanism has always been the same. The heavens move without ceasing but so also does water flow." Water clock have been used in Egypt since the 15th century B.C.

The early Chinese, Japanese and Koreans also measured time with fire. A fire-clock consisted of a continuous line of powdered incense woven into an elaborate design or seal. Time was indicated by the place in the seal reached by fire. One of the most sophisticated of these— 'hundred-gradations incense seal' —was made in China in 1073 when a drought dried up wells and made it difficult to use customary water clocks.

One of the most elaborate clocks the world has ever seen—made in 1094 by Su Song—was called the "Heavenly Clockwork" in honor of the emperor, the "Son of Heaven." The clock took over a decade to design and construct but was only seen by the Emperor and few high official before it was melted down in 1094. When a new emperor came to power, according to custom, the calendar of the previous emperor was labeled "obsolete" and destroyed. It wasn't until the late 16th century when Jesuit priests introduced Italian clocks that China witnessed clocks of such sophistication again. [Source: "The Discoverers" by Daniel Boorstin]

Great 11th Century Water Clock of Su Song

Clock Tower in Su Song's book

Su Song’s "Heavenly Clockwork" was a 10-meter-high, five-story, pagoda-like structure that utilized flowing water to turn a giant water wheel at a precise, steady rate. Employing dozens of wheels and bristling with shafts and levers, this “combination planetarium-clock signaled the quarter hours with gongs, bells, and a sort of glockenspiel. Its crowning feature was a water-triggered device called an escarpment that stopped the clock's movement at set intervals, forcing it to run at a steady state."

On each of the five stories a procession of manikins carrying bells and gongs marked the hours. Inside the three-story-high main tower was a huge clockwork, driven by water flowing at ground level and alternately filling and emptying the scoops on a vertical rotating wheel. On the topmost platform, reached by a separate outside staircase, was a huge bronze power-driven armillary sphere within which there rotated automatically a celestial globe.

Boorstin wrote: "Every quarter-hour the whole structure reverberated to bells and gongs, the splashing of water, the creaking of giant wheels, the marching of manikins. The escapement that stopped and started the machine as it marked off the units of time was, of course, the crucial element. Su Song's ingenious water escapement made use of the fluid qualities of provide the staccato motion required in a mechanical timepiece." [Source: "The Discoverers" by Daniel Boorstin]

Su Song described his own machine as follows: "There are ninety-six jacks. They are arranged to correspond in timing with the sounding of “quarters” on the bell-and-drum floor of this belfry...At sunset a jack wearing red appears to report, and then after two and a half “quarters” there comes another in green to report darkness. The night-watches each contain five subdivisions. A jack wearing red appears at the beginning of the night-watches, marking the first subdivisions, while for the remaining four subdivisions the jacks are all green. In this way there are twenty-five jacks for the five night-watches. When the time of waiting for dawn comes, with its ten "quarters," a jack in green comes out to report this. Then dawn with its two and a half "quarters" is marked by another jack wearing green, and sunrise is reported by a jack wearing red. All these jacks appear in the central doorway." [Source: "The Discoverers" by Daniel Boorstin]

A model of this clock is now in the Beijing Museum. 1990

Image Sources: 1) Early paper. China Page website; 2) Early printing, China Page website; 3) Earliest printed book, Brooklyn University; 4) Paper money Brooklyn College; 5) Early star map Brooklyn College; 6) Song water clock photo by Conrad Jung

Text Sources: Asia for Educators, Columbia University ; University of Washington’s Visual Sourcebook of Chinese Civilization, /=\; New York Times, Washington Post, Los Angeles Times, Times of London, National Geographic, The New Yorker, Time, Newsweek, Reuters, AP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.

Last updated August 2021

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