Ma Jun (mechanical engineer)
- For the environmentalist, see Ma Jun (environmentalist).
Ma Jun (200 - 265 AD, Wade-Giles: Ma Chün) was a mechanical engineer during the Three Kingdoms era of China. According to the poet and philosopher Fu Xuan, Ma Jun was born in Fu-feng, located in the Wei River valley betweem Wugong and Baoji. He learned under and was tutored by the Chinese master (tzu) named De-Heng. His most notable invention was that of the South Pointing Chariot, a directional compass which actually had no magnetic function, but was operated by use of differential (mechanical device) gears. Because of this device and others, Ma Jun is known as one of the most brilliant mechanical engineers and inventors of his day (alongside Zhang Heng of the earlier Eastern Han Dynasty).
Life and Achievements
Ma Jun was a somewhat distinguished official serving under the northern state of Wei, becoming a Policy Review Advisor (Wade-Giles: Chi Shih Chung). Ma Jun once oversaw the construction of Chong Hua's palace, under the orders of Cao Rui. Ma Jun was very well known in Wei as being very gifted in the way of designing weapons along with certain types of contraptions, and was praised especially Fu Xuan in an essay of his.
Ma Jun once got into a dispute with the Permanent Counsellor Caotang Long and the Cavalry General Qin Lang at court over the concept of the south-pointing carriage, or the South Pointing Chariot. The minister and the general mocked Ma Jun for his belief in historical texts that the South Pointing Chariot had actually been invented. Ma Jun retorted against them, saying "Empty arguments with words cannot (in any way) compare with a test which will show practical results". After being instructed to make such a device, Ma Jun was able to not only invent a mechanically-operated directional compass, but arguably the first device to employ any sort of differential gear. There is also the Antikythera mechanism of the Greek-Hellenized Aegean world which purportedly used a differential gear.
For the Emperor Ming of Wei, he once invented an intricate hydraulic-powered, mechanical-operated puppet theatre (much more complex than the mechanical puppet set discovered by Liu Bang, first Emperor of the Han Dynasty, when he observed the state-absorbed items taken from the old treasury of the deceased Qin Shi Huang). His puppet theatre is similar to that of a Greek model invented by Heron of Alexandria, the difference being that the latter used instead a rotating cogwheel with ropes and pulleys to operate his mechanical theatre. Joseph Needham describes Ma Jun's mechanical theatre in a passage taken from the Sanguo Zhi, Records of the Three Kingdoms:
Certain persons offered to the emperor a theatre of puppets, which could be set up in various scenes, but all motionless. The emperor asked whether they could be made to move, and Ma Chün [Ma Jun] said that they could. The emperor asked whether it could be possible to make the whole thing more ingenious, and again Ma Chün [Ma Jun] said yes, and accepted the command to do it. He took a large piece of wood and fashioned it into the shape of a wheel which rotated in a horizontal position by the power of unseen water. He furthermore arranged images of singing-girls which played music and danced, and when (a particular) puppet came upon the scene, other wooden men beat drums and blew upon flutes. Ma Chün [Ma Jun] also made a mountain with wooden images dancing on balls, throwing swords about, hanging upside down on rope ladders, and generally behaving in an assured and easy manner. Government officials were in their offices, pounding and grinding was going on, cocks were fighting, and all was continually changing and moving ingeniously with a hundred variations... (Needham, 158)
Ma Jun was also responsible for the construction of square-pallet chain pumps meant for irrigation. However, Ma Jun was not the first in China to invent such a device. An earlier account was made by in the year 80 by philosopher Wang Chong, in his Discourses Weighed in the Balance. The Eastern Han Dynasty court eunuch Zhang Rang once ordered the engineer Bi Lan to construct a series of chain pumps outside the capital city of Luoyang, used for irrigation and means of fresh water source. Ma Jun constructed his square-pallet chain pumps to water newly designated garden space established within Luoyang by Emperor Ming of Wei (Cao Rui).
References
- Needham, Joseph (1986). Science and Civilization in China: Volume 4, Part II. Taipei: Caves Books, Ltd.