Science and technology of the Han dynasty
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Han dynasty The Han dynasty (, ; ) was an imperial dynasty of China (202 BC – 9 AD, 25–220 AD), established by Liu Bang (Emperor Gao) and ruled by the House of Liu. The dynasty was preceded by the short-lived Qin dynasty (221–207 BC) and a warr ...
(206 BCE – 220 CE) of
early imperial China The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dynasty (c. 1600–1046 BC), during the reign of king Wu Ding. Ancient historical texts such as the ''Book of Documents'' (early chapter ...
, divided between the eras of Western Han (206 BCE – 9 CE, when the capital was at
Chang'an Chang'an (; ) is the traditional name of Xi'an. The site had been settled since Neolithic times, during which the Yangshao culture was established in Banpo, in the city's suburbs. Furthermore, in the northern vicinity of modern Xi'an, Qin Shi ...
), the
Xin dynasty The Xin dynasty (; ), also known as Xin Mang () in Chinese historiography, was a short-lived Chinese imperial dynasty which lasted from 9 to 23 AD, established by the Han dynasty consort kin Wang Mang, who usurped the throne of the Emperor Ping o ...
of
Wang Mang Wang Mang () (c. 45 – 6 October 23 CE), courtesy name Jujun (), was the founder and the only Emperor of China, emperor of the short-lived Chinese Xin dynasty. He was originally an official and consort kin of the Han dynasty and later ...
(r. 9–23 CE), and Eastern Han (25–220 CE, when the capital was at
Luoyang Luoyang is a city located in the confluence area of Luo River (Henan), Luo River and Yellow River in the west of Henan province. Governed as a prefecture-level city, it borders the provincial capital of Zhengzhou to the east, Pingdingshan to the ...
, and after 196 CE at
Xuchang Xuchang (; postal: Hsuchang) is a prefecture-level city in central Henan province of China, province in Central China. It borders the provincial capital of Zhengzhou to the northwest, Kaifeng to the northeast, Zhoukou to the east, Luohe to the s ...
), witnessed some of the most significant advancements in premodern Chinese science and technology. There were great innovations in
metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the sc ...
. In addition to Zhou-era China's (c. 1046 – 256 BCE) previous inventions of the
blast furnace A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being "forced" or supplied above atmospheric ...
and
cupola furnace A cupola or cupola furnace is a melting device used in foundries that can be used to melt cast iron, Ni-resist iron and some bronzes. The cupola can be made almost any practical size. The size of a cupola is expressed in diameters and can range f ...
to make
pig iron Pig iron, also known as crude iron, is an intermediate product of the iron industry in the production of steel which is obtained by smelting iron ore in a blast furnace. Pig iron has a high carbon content, typically 3.8–4.7%, along with silic ...
and
cast iron Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
, respectively, the Han period saw the development of
steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
and
wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.08%) in contrast to that of cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag Inclusion (mineral), inclusions (up to 2% by weight), which give it a ...
by use of the
finery forge A finery forge is a forge used to produce wrought iron from pig iron by decarburization in a process called "fining" which involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Finery ...
and puddling process. With the drilling of deep
borehole A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water ( drilled water well and tube well), other liquids (such as petro ...
s into the earth, the Chinese used not only
derrick A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and a ...
s to lift
brine Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for br ...
up to the surface to be boiled into
salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
, but also set up bamboo-crafted
pipeline transport Pipeline transport is the long-distance transportation of a liquid or gas through a system of pipes—a pipeline—typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than of pipeline in 120 countr ...
systems which brought
natural gas Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...
as fuel to the furnaces. Smelting techniques were enhanced with inventions such as the
waterwheel A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a wheel (usually constructed from wood or metal), with a number of blades or buckets ...
-powered
bellows A bellows or pair of bellows is a device constructed to furnish a strong blast of air. The simplest type consists of a flexible bag comprising a pair of rigid boards with handles joined by flexible leather sides enclosing an approximately airtigh ...
; the resulting widespread distribution of iron tools facilitated the growth of agriculture. For tilling the soil and planting straight rows of crops, the improved heavy-moldboard plough with three iron
plowshare In agriculture, a plowshare ( US) or ploughshare ( UK; ) is a component of a plow (or plough). It is the cutting or leading edge of a moldboard which closely follows the coulter (one or more ground-breaking spikes) when plowing. The plowshar ...
s and sturdy multiple-tube iron
seed drill A seed drill is a device used in agriculture that sows seeds for crops by positioning them in the soil and burying them to a specific depth while being dragged by a tractor. This ensures that seeds will be distributed evenly. The seed drill sow ...
were invented in the Han, which greatly enhanced production yields and thus sustained population growth. The method of supplying
irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...
ditches with water was improved with the invention of the mechanical
chain pump The chain pump is type of a water pump in which several circular discs are positioned on an endless chain. One part of the chain dips into the water, and the chain runs through a tube, slightly bigger than the diameter of the discs. As the chain is ...
powered by the rotation of a waterwheel or draft animals, which could transport irrigation water up elevated terrains. The waterwheel was also used for operating
trip hammer A trip hammer, also known as a tilt hammer or helve hammer, is a massive powered hammer. Traditional uses of trip hammers include pounding, decorticating and polishing of grain in agriculture. In mining, trip hammers were used for crushing meta ...
s in pounding grain and in rotating the metal rings of the mechanical-driven astronomical
armillary sphere An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of ...
representing the
celestial sphere In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, ...
around the Earth. The quality of life was improved with many Han inventions. The Han Chinese had hempen-bound bamboo scrolls to write on, yet by the 2nd century CE had invented the
papermaking Papermaking is the manufacture of paper and cardboard, which are used widely for printing, writing, and packaging, among many other purposes. Today almost all paper is made using industrial machinery, while handmade paper survives as a speciali ...
process which created a writing medium that was both cheap and easy to produce. The invention of the
wheelbarrow A wheelbarrow is a small hand-propelled vehicle, usually with just one wheel, designed to be pushed and guided by a single person using two handles at the rear, or by a sail to push the ancient wheelbarrow by wind. The term "wheelbarrow" is mad ...
aided in the hauling of heavy loads. The maritime ''junk'' ship and stern-mounted steering
rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...
enabled the Chinese to venture out of calmer waters of interior lakes and rivers and into the open sea. The invention of the
grid reference A projected coordinate system, also known as a projected coordinate reference system, a planar coordinate system, or grid reference system, is a type of spatial reference system that represents locations on the Earth using cartesian coordin ...
for maps and
raised-relief map A raised-relief map, terrain model or embossed map is a three-dimensional representation, usually of terrain, materialized as a physical artifact. When representing terrain, the vertical dimension is usually exaggerated by a factor between fiv ...
allowed for better navigation of their terrain. In medicine, they used new
herbal remedies Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedie ...
to cure illnesses,
calisthenics Calisthenics (American English) or callisthenics (British English) ( /ˌkælɪsˈθɛnɪks/) is a form of strength training consisting of a variety of movements that exercise large muscle groups (gross motor movements), such as standing, graspi ...
to keep physically fit, and regulated
diet Diet may refer to: Food * Diet (nutrition), the sum of the food consumed by an organism or group * Dieting, the deliberate selection of food to control body weight or nutrient intake ** Diet food, foods that aid in creating a diet for weight loss ...
s to avoid diseases. Authorities in the capital were warned ahead of time of the direction of sudden
earthquakes An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
with the invention of the
seismometer A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The outpu ...
that was tripped by a vibration-sensitive
pendulum A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the ...
device. To mark the passing of the seasons and special occasions, the Han Chinese used two variations of the
lunisolar calendar A lunisolar calendar is a calendar in many cultures, combining lunar calendars and solar calendars. The date of Lunisolar calendars therefore indicates both the Moon phase and the time of the solar year, that is the position of the Sun in the Ea ...
, which were established due to efforts in
astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
and
mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
. Han-era Chinese advancements in mathematics include the discovery of
square root In mathematics, a square root of a number is a number such that ; in other words, a number whose ''square'' (the result of multiplying the number by itself, or  ⋅ ) is . For example, 4 and −4 are square roots of 16, because . E ...
s,
cube root In mathematics, a cube root of a number is a number such that . All nonzero real numbers, have exactly one real cube root and a pair of complex conjugate cube roots, and all nonzero complex numbers have three distinct complex cube roots. Fo ...
s, the
Pythagorean theorem In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse (the side opposite t ...
,
Gaussian elimination In mathematics, Gaussian elimination, also known as row reduction, is an algorithm for solving systems of linear equations. It consists of a sequence of operations performed on the corresponding matrix of coefficients. This method can also be used ...
, the
Horner scheme In mathematics and computer science, Horner's method (or Horner's scheme) is an algorithm for polynomial evaluation. Although named after William George Horner, this method is much older, as it has been attributed to Joseph-Louis Lagrange by Hor ...
, improved calculations of '' pi'', and
negative number In mathematics, a negative number represents an opposite. In the real number system, a negative number is a number that is less than zero. Negative numbers are often used to represent the magnitude of a loss or deficiency. A debt that is owed m ...
s. Hundreds of new roads and canals were built to facilitate transport, commerce, tax collection, communication, and movement of military troops. The Han-era Chinese also employed several types of bridges to cross waterways and deep gorges, such as
beam bridge Beam bridges are the simplest structural forms for bridge spans supported by an abutment or pier at each end. No moments are transferred throughout the support, hence their structural type is known as '' simply supported''. The simplest beam ...
s,
arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct ...
s,
simple suspension bridge A simple suspension bridge (also rope bridge, swing bridge (in New Zealand), suspended bridge, hanging bridge and catenary bridge) is a primitive type of bridge in which the deck of the bridge lies on two parallel load-bearing cables that ar ...
s, and
pontoon bridge A pontoon bridge (or ponton bridge), also known as a floating bridge, uses float (nautical), floats or shallow-draft (hull), draft boats to support a continuous deck for pedestrian and vehicle travel. The buoyancy of the supports limits the maxi ...
s. Han ruins of defensive city walls made of
brick A brick is a type of block used to build walls, pavements and other elements in masonry construction. Properly, the term ''brick'' denotes a block composed of dried clay, but is now also used informally to denote other chemically cured cons ...
or
rammed earth Rammed earth is a technique for constructing foundations, floors, and walls using compacted natural raw materials such as earth, chalk, lime, or gravel. It is an ancient method that has been revived recently as a sustainable building method. ...
still stand today.


Modern perspectives

Jin Guantao, a professor of the Institute of Chinese Studies at the
Chinese University of Hong Kong The Chinese University of Hong Kong (CUHK) is a public research university in Ma Liu Shui, Hong Kong, formally established in 1963 by a charter granted by the Legislative Council of Hong Kong. It is the territory's second-oldest university an ...
, Fan Hongye, a research fellow with the
Chinese Academy of Sciences The Chinese Academy of Sciences (CAS); ), known by Academia Sinica in English until the 1980s, is the national academy of the People's Republic of China for natural sciences. It has historical origins in the Academia Sinica during the Republ ...
' Institute of Science Policy and Managerial Science, and Liu Qingfeng, a professor of the Institute of Chinese Culture at the Chinese University of Hong Kong, assert that the latter part of the Han dynasty was a unique period in the history of premodern Chinese science and technology.Jin, Fan, & Liu (1996), 178–179. They compare it to the incredible pace of scientific and technological growth during the
Song dynasty The Song dynasty (; ; 960–1279) was an imperial dynasty of China that began in 960 and lasted until 1279. The dynasty was founded by Emperor Taizu of Song following his usurpation of the throne of the Later Zhou. The Song conquered the rest ...
(960–1279). However, they also argue that without the influence of proto-scientific precepts in the ancient philosophy of
Mohism Mohism or Moism (, ) was an ancient Chinese philosophy of ethics and logic, rational thought, and science developed by the academic scholars who studied under the ancient Chinese philosopher Mozi (c. 470 BC – c. 391 BC), embodied in an epony ...
, Chinese science continued to lack a definitive structure:
From the middle and late Eastern Han to the early Wei and Jin dynasties, the net growth of ancient Chinese science and technology experienced a peak (second only to that of the Northern Song dynasty) ...Han studies of the Confucian classics, which for a long time had hindered the socialization of science, were declining. If Mohism, rich in scientific thought, had rapidly grown and strengthened, the situation might have been very favorable to the development of a scientific structure. However, this did not happen because the seeds of the primitive structure of science were never formed. During the late Eastern Han, disastrous upheavals again occurred in the process of social transformation, leading to the greatest social disorder in Chinese history. One can imagine the effect of this calamity on science.
Joseph Needham Noel Joseph Terence Montgomery Needham (; 9 December 1900 – 24 March 1995) was a British biochemist, historian of science and sinologist known for his scientific research and writing on the history of Chinese science and technology, in ...
(1900–1995), a late Professor from the
University of Cambridge , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...
and author of the groundbreaking ''
Science and Civilisation in China ''Science and Civilisation in China'' (1954–present) is an ongoing series of books about the history of science and technology in China published by Cambridge University Press. It was initiated and edited by British historian Joseph Needham (1 ...
'' series, stated that the "Han time (especially the Later Han) was one of the relatively important periods as regards the history of science in China."Needham (1972), 111. He noted the advancements during Han of
astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
and calendrical sciences, the "beginnings of systematic
botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...
and
zoology Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...
", as well as the
philosophical skepticism Philosophical skepticism ( UK spelling: scepticism; from Greek σκέψις ''skepsis'', "inquiry") is a family of philosophical views that question the possibility of knowledge. It differs from other forms of skepticism in that it even reject ...
and rationalist thought embodied in Han works such as the ''
Lunheng The ''Lunheng'', also known by numerous English translations, is a wide-ranging Chinese classic text by Wang Chong (27- ). First published in 80, it contains critical essays on natural science and Chinese mythology, philosophy, and literature ...
'' by the philosopher
Wang Chong Wang Chong (; 27 – c. 97 AD), courtesy name Zhongren (仲任), was a Chinese astronomer, meteorologist, naturalist, philosopher, and writer active during the Han Dynasty. He developed a rational, secular, naturalistic and mechanistic account ...
(27–100 CE).


Writing materials

The most common writing mediums found in archaeological digs from ancient sites predating the Han period are shells and bones as well as bronzewares.Loewe (1968), 89. In the beginning of the Han period, the chief writing mediums were bamboo () and
clay tablet In the Ancient Near East, clay tablets (Akkadian ) were used as a writing medium, especially for writing in cuneiform, throughout the Bronze Age and well into the Iron Age. Cuneiform characters were imprinted on a wet clay tablet with a stylu ...
s,
silk Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the coc ...
cloth, strips of soft wood, and rolled scrolls made of strips of
bamboo Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, bu ...
sewn together with
hemp Hemp, or industrial hemp, is a botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants o ...
en string passed through drilled holes (册) and secured with clay stamps. The written characters on these narrow flat strips of bamboo were arranged into vertical columns. While maps drawn in ink on flat silk cloths have been found in the tomb of the Marquess of Dai (interred in 168 BCE at
Mawangdui Mawangdui () is an archaeological site located in Changsha, China. The site consists of two saddle-shaped hills and contained the tombs of three people from the Changsha Kingdom during the western Han dynasty (206 BC – 9 AD): the Chancellor Li ...
,
Hunan Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi to ...
province), the earliest known
paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...
map found in China, dated 179–141 BCE and located at
Fangmatan Fangmatan () is an archeological site located near Tianshui in China's Gansu province. The site was located within the Qin state, and includes several burials dating from the Warring States period through to the early Western Han. Tomb 1 The date ...
(near
Tianshui Tianshui is the second-largest cities in Gansu, city in Gansu list of Chinese provinces, Province, China. The city is located in the southeast of the province, along the upper reaches of the Wei River and at the boundary of the Loess Plateau and ...
,
Gansu Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibet ...
province), is incidentally the oldest known piece of paper.Buisseret (1998), 12. Yet Chinese hempen paper of the Western Han and early Eastern Han eras was of a coarse quality and used primarily as
wrapping paper Gift wrapping is the act of enclosing a gift in some sort of material. Wrapping paper is a kind of paper designed for gift wrapping. An alternative to gift wrapping is using a gift box or bag. A wrapped or boxed gift may be held closed with ribb ...
.Needham (1986e), 1–2, 40–41, 122–123, 228. The
papermaking Papermaking is the manufacture of paper and cardboard, which are used widely for printing, writing, and packaging, among many other purposes. Today almost all paper is made using industrial machinery, while handmade paper survives as a speciali ...
process was not formally introduced until the Eastern Han court eunuch
Cai Lun Cai Lun (; courtesy name: Jingzhong (); – 121 CE), formerly romanized as Ts'ai Lun, was a Chinese eunuch court official of the Eastern Han dynasty. He is traditionally regarded as the inventor of paper and the modern papermaking process ...
(50–121 CE) created a process in 105 where
mulberry tree ''Morus'', a genus of flowering plants in the family Moraceae, consists of diverse species of deciduous trees commonly known as mulberries, growing wild and under cultivation in many temperate world regions. Generally, the genus has 64 identif ...
bark, hemp, old linens, and fish nets were boiled together to make a pulp that was pounded, stirred in water, and then dunked with a wooden sieve containing a
reed Reed or Reeds may refer to: Science, technology, biology, and medicine * Reed bird (disambiguation) * Reed pen, writing implement in use since ancient times * Reed (plant), one of several tall, grass-like wetland plants of the order Poales * ...
mat that was shaken, dried, and bleached into sheets of paper. The oldest known piece of paper with writing on it comes from the ruins of a Chinese
watchtower A watchtower or watch tower is a type of fortification used in many parts of the world. It differs from a regular tower in that its primary use is military and from a turret in that it is usually a freestanding structure. Its main purpose is to ...
at Tsakhortei,
Alxa League Alxa League or Ālāshàn League (; mn, , Mongolian Cyrillic. Алшаа аймаг) is one of 12 prefecture level divisions and 3 extant leagues of Inner Mongolia. The league borders Mongolia to the north, Bayan Nur to the northeast, Wuhai ...
,
Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an autonomous region of the People's Republic of China. Its border includes most of the length of China's border with the country of Mongolia. Inner Mongolia also accounts for a ...
, dated precisely to 110 CE when the Han garrison abandoned the area following a nomadic
Xiongnu The Xiongnu (, ) were a tribal confederation of nomadic peoples who, according to ancient Chinese sources, inhabited the eastern Eurasian Steppe from the 3rd century BC to the late 1st century AD. Modu Chanyu, the supreme leader after 20 ...
attack.Cotterell (2004), 11. By the 3rd century, paper became one of China's chief writing mediums.Needham (1986e), 1–2.


Ceramics

The Han
ceramics A ceramic is any of the various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelain ...
industry was upheld by private businesses as well as local government agencies.Wang (1982), 146–147. Ceramics were used in domestic wares and utensils as well as construction materials for roof
tile Tiles are usually thin, square or rectangular coverings manufactured from hard-wearing material such as ceramic, stone, metal, baked clay, or even glass. They are generally fixed in place in an array to cover roofs, floors, walls, edges, or o ...
s and
brick A brick is a type of block used to build walls, pavements and other elements in masonry construction. Properly, the term ''brick'' denotes a block composed of dried clay, but is now also used informally to denote other chemically cured cons ...
s.Wang (1982), 147–149. Han dynasty grey
pottery Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and por ...
—its color derived from the
clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...
that was used—was superior to earlier Chinese grey pottery due to the Han people's use of larger
kiln A kiln is a thermally insulated chamber, a type of oven, that produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes. Kilns have been used for millennia to turn objects made from clay int ...
chambers, longer firing tunnels, and improved chimney designs.Wang (1982), 142–143. Kilns of the Han dynasty making grey pottery were able to reach firing temperatures above . However, hard southern Chinese pottery made from a dense adhesive clay native only in the south (i.e.
Guangdong Guangdong (, ), alternatively romanized as Canton or Kwangtung, is a coastal province in South China on the north shore of the South China Sea. The capital of the province is Guangzhou. With a population of 126.01 million (as of 2020) ...
,
Guangxi Guangxi (; ; Chinese postal romanization, alternately romanized as Kwanghsi; ; za, Gvangjsih, italics=yes), officially the Guangxi Zhuang Autonomous Region (GZAR), is an Autonomous regions of China, autonomous region of the People's Republic ...
,
Hunan Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi to ...
,
Jiangxi Jiangxi (; ; formerly romanized as Kiangsi or Chianghsi) is a landlocked province in the east of the People's Republic of China. Its major cities include Nanchang and Jiujiang. Spanning from the banks of the Yangtze river in the north int ...
,
Fujian Fujian (; alternately romanized as Fukien or Hokkien) is a province on the southeastern coast of China. Fujian is bordered by Zhejiang to the north, Jiangxi to the west, Guangdong to the south, and the Taiwan Strait to the east. Its capi ...
,
Zhejiang Zhejiang ( or , ; , also romanized as Chekiang) is an eastern, coastal province of the People's Republic of China. Its capital and largest city is Hangzhou, and other notable cities include Ningbo and Wenzhou. Zhejiang is bordered by Jiang ...
, and southern
Jiangsu Jiangsu (; ; pinyin: Jiāngsū, Postal romanization, alternatively romanized as Kiangsu or Chiangsu) is an Eastern China, eastern coastal Provinces of the People's Republic of China, province of the China, People's Republic of China. It is o ...
) was fired at even higher temperatures than grey pottery during the Han. Glazed pottery of the
Shang The Shang dynasty (), also known as the Yin dynasty (), was a Chinese royal dynasty founded by Tang of Shang (Cheng Tang) that ruled in the Yellow River valley in the second millennium BC, traditionally succeeding the Xia dynasty and f ...
(c. 1600 – c. 1050 BCE) and Zhou (c. 1050 – 256 BCE) dynasties were fired at high temperatures, but by the mid Western Han (206 BCE – 9 CE), a brown-glazed ceramic was made which was fired at the low temperature of , followed by a green-glazed ceramic which became popular in the Eastern Han (25–220 CE).Wang (1982), 143–145.
Wang Zhongshu Wang Zhongshu (; 15 October 1925 – 24 September 2015) was a Chinese archaeologist who helped to establish and develop the field of archaeology in China. One of the most prominent Asian archaeologists, he was awarded the Grand Prize of the Fuk ...
states that the light-green
stoneware Stoneware is a rather broad term for pottery or other ceramics fired at a relatively high temperature. A modern technical definition is a Vitrification#Ceramics, vitreous or semi-vitreous ceramic made primarily from stoneware clay or non-refracto ...
known as
celadon ''Celadon'' () is a term for pottery denoting both wares glazed in the jade green celadon color, also known as greenware or "green ware" (the term specialists now tend to use), and a type of transparent glaze, often with small cracks, that was ...
was thought to exist only since the
Three Kingdoms The Three Kingdoms () from 220 to 280 AD was the tripartite division of China among the dynastic states of Cao Wei, Shu Han, and Eastern Wu. The Three Kingdoms period was preceded by the Han dynasty#Eastern Han, Eastern Han dynasty and wa ...
period (220–265 CE) onwards, but argues that ceramic shards found at Eastern Han (25–220 CE) sites of Zhejiang province can be classified as
celadon ''Celadon'' () is a term for pottery denoting both wares glazed in the jade green celadon color, also known as greenware or "green ware" (the term specialists now tend to use), and a type of transparent glaze, often with small cracks, that was ...
.Wang (1982), 145. However, Richard Dewar argues that true celadon was not created in China until the early
Song dynasty The Song dynasty (; ; 960–1279) was an imperial dynasty of China that began in 960 and lasted until 1279. The dynasty was founded by Emperor Taizu of Song following his usurpation of the throne of the Later Zhou. The Song conquered the rest ...
(960–1279) when Chinese kilns were able to reach a minimum furnace temperature of , with a preferred range of for celadon.Dewar (2002), 42.


Metallurgy


Furnaces and smelting techniques

A
blast furnace A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. ''Blast'' refers to the combustion air being "forced" or supplied above atmospheric ...
converts raw
iron oxide Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of whic ...
into
iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
, which can be remelted in a
cupola furnace A cupola or cupola furnace is a melting device used in foundries that can be used to melt cast iron, Ni-resist iron and some bronzes. The cupola can be made almost any practical size. The size of a cupola is expressed in diameters and can range f ...
to produce
cast iron Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
. The earliest specimens of cast iron found in China date to the 5th century BCE during the late
Spring and Autumn period The Spring and Autumn period was a period in Chinese history from approximately 770 to 476 BC (or according to some authorities until 403 BC) which corresponds roughly to the first half of the Eastern Zhou period. The period's name derives fr ...
, yet the oldest discovered blast furnaces date to the 3rd century BCE and the majority date to the period after
Emperor Wu of Han Emperor Wu of Han (156 – 29 March 87BC), formally enshrined as Emperor Wu the Filial (), born Liu Che (劉徹) and courtesy name Tong (通), was the seventh emperor of the Han dynasty of ancient China, ruling from 141 to 87 BC. His reign la ...
(r. 141–87 BCE) established a government monopoly over the iron industry in 117 BCE (most of the discovered iron works sites built before this date were merely
foundries A foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal into a mold, and removing the mold material after the metal has solidified as it cools. The most common metals pr ...
which recast iron that had been smelted elsewhere). Iron ore smelted in blast furnaces during the Han was rarely if ever cast directly into permanent molds; instead, the pig iron scraps were remelted in the cupola furnace to make cast iron.Wagner (2001), 75–76. Cupola furnaces utilized a
cold blast Cold blast, in ironmaking, refers to a metallurgical furnace where air is not preheated before being blown into the furnace. This represents the earliest stage in the development of ironmaking. Until the 1820s, the use of cold air was thought to b ...
traveling through
tuyere A tuyere or tuyère (; ) is a tube, nozzle or pipe through which air is blown into a furnace or hearth.W. K. V. Gale, The iron and Steel industry: a dictionary of terms (David and Charles, Newton Abbot 1972), 216–217. Air or oxygen is injec ...
pipes from the bottom and over the top where the charge of
charcoal Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, cal ...
and pig iron was introduced. The air traveling through the tuyere pipes thus became a
hot blast Hot blast refers to the preheating of air blown into a blast furnace or other metallurgical process. As this considerably reduced the fuel consumed, hot blast was one of the most important technologies developed during the Industrial Revolution. ...
once it reached the bottom of the furnace. Although Chinese civilization lacked the
bloomery A bloomery is a type of metallurgical furnace once used widely for smelting iron from its oxides. The bloomery was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called a ''bloom ...
, the Han Chinese were able to make
wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.08%) in contrast to that of cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag Inclusion (mineral), inclusions (up to 2% by weight), which give it a ...
when they injected too much
oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
into the cupola furnace, causing
decarburization Decarburization (or decarbonization) is the process of decreasing carbon content, which is the opposite of carburization. The term is typically used in metallurgy, describing the decrease of the content of carbon in metals (usually steel). Deca ...
. The Han-era Chinese were also able to convert cast iron and pig iron into wrought iron and
steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
by using the
finery forge A finery forge is a forge used to produce wrought iron from pig iron by decarburization in a process called "fining" which involved liquifying cast iron in a fining hearth and removing carbon from the molten cast iron through oxidation. Finery ...
and puddling process, the earliest specimens of such dating to the 2nd century BCE and found at Tieshengguo near
Mount Song Mount Song (, "lofty mountain") is an isolated mountain range in north central China's Henan Province, along the southern bank of the Yellow River. It is known in literary and folk tradition as the central mountain of the Five Great Mountains of ...
of
Henan Henan (; or ; ; alternatively Honan) is a landlocked province of China, in the central part of the country. Henan is often referred to as Zhongyuan or Zhongzhou (), which literally means "central plain" or "midland", although the name is al ...
province. The semisubterranean walls of these furnaces were lined with
refractory In materials science, a refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractories are polycrystalline, polyphase, ...
bricks and had bottoms made of refractory clay. Besides charcoal made of wood,
Wang Zhongshu Wang Zhongshu (; 15 October 1925 – 24 September 2015) was a Chinese archaeologist who helped to establish and develop the field of archaeology in China. One of the most prominent Asian archaeologists, he was awarded the Grand Prize of the Fuk ...
states that another furnace fuel used during the Han were "coal cakes", a mixture of
coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dea ...
powder, clay, and
quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical form ...
.Wang (1982), 126.


Use of steel, iron, and bronze

Donald B. Wagner writes that most domestic iron tools and implements produced during the Han were made of cheaper and more brittle cast iron, whereas
the military A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
preferred to use wrought iron and steel weaponry due to their more durable qualities. During the Han dynasty, the typical
bronze Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such ...
sword found in the
Warring States period The Warring States period () was an era in History of China#Ancient China, ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period and concluded ...
was gradually replaced with an iron sword measuring roughly in length. The ancient
dagger-axe The dagger-axe () is a type of pole weapon that was in use from the Erlitou culture until the Han dynasty in China. It consists of a dagger-shaped blade, mounted by its tang to a perpendicular wooden shaft. The earliest dagger-axe blades were ...
(''ge'') made of bronze was still used by Han soldiers, although it was gradually phased out by iron spears and iron ''ji'' halberds.Wang (1982), 123. Even
arrowhead An arrowhead or point is the usually sharpened and hardened tip of an arrow, which contributes a majority of the projectile mass and is responsible for impacting and penetrating a target, as well as to fulfill some special purposes such as sign ...
s, which were traditionally made of bronze, gradually only had a bronze tip and iron shaft, until the end of the Han when the entire arrowhead was made solely of iron. Farmers,
carpenter Carpentry is a skilled trade and a craft in which the primary work performed is the cutting, shaping and installation of building materials during the construction of buildings, Shipbuilding, ships, timber bridges, concrete formwork, etc. ...
s, bamboo craftsmen,
stonemason Stonemasonry or stonecraft is the creation of buildings, structures, and sculpture using stone as the primary material. It is one of the oldest activities and professions in human history. Many of the long-lasting, ancient shelters, temples, mo ...
s, and
rammed earth Rammed earth is a technique for constructing foundations, floors, and walls using compacted natural raw materials such as earth, chalk, lime, or gravel. It is an ancient method that has been revived recently as a sustainable building method. ...
builders had at their disposal iron tools such as the
plowshare In agriculture, a plowshare ( US) or ploughshare ( UK; ) is a component of a plow (or plough). It is the cutting or leading edge of a moldboard which closely follows the coulter (one or more ground-breaking spikes) when plowing. The plowshar ...
,
pickaxe A pickaxe, pick-axe, or pick is a generally T-shaped hand tool used for Leverage (mechanics), prying. Its head is typically metal, attached perpendicularly to a longer handle, traditionally made of wood, occasionally metal, and increasingly ...
,
spade A spade is a tool primarily for digging consisting of a long handle and blade, typically with the blade narrower and flatter than the common shovel. Early spades were made of riven wood or of animal bones (often shoulder blades). After the a ...
,
shovel A shovel is a tool used for digging, lifting, and moving bulk materials, such as soil, coal, gravel, snow, sand, or ore. Most shovels are hand tools consisting of a broad blade fixed to a medium-length handle. Shovel blades are usually made of ...
, hoe,
sickle A sickle, bagging hook, reaping-hook or grasshook is a single-handed agricultural tool designed with variously curved blades and typically used for harvesting, or reaping, grain crops or cutting succulent forage chiefly for feeding livestock, ei ...
,
axe An axe ( sometimes ax in American English; see spelling differences) is an implement that has been used for millennia to shape, split and cut wood, to harvest timber, as a weapon, and as a ceremonial or heraldic symbol. The axe has ma ...
,
adze An adze (; alternative spelling: adz) is an ancient and versatile cutting tool similar to an axe but with the cutting edge perpendicular to the handle rather than parallel. Adzes have been used since the Stone Age. They are used for smoothing ...
,
hammer A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nails into wood, to shape metal (as w ...
,
chisel A chisel is a tool with a characteristically shaped cutting edge (such that wood chisels have lent part of their name to a particular grind) of blade on its end, for carving or cutting a hard material such as wood, stone, or metal by hand, stru ...
,
knife A knife ( : knives; from Old Norse 'knife, dirk') is a tool or weapon with a cutting edge or blade, usually attached to a handle or hilt. One of the earliest tools used by humanity, knives appeared at least 2.5 million years ago, as evidenced ...
,
saw A saw is a tool consisting of a tough blade, wire, or chain with a hard toothed edge. It is used to cut through material, very often wood, though sometimes metal or stone. The cut is made by placing the toothed edge against the material and mo ...
,
scratch awl A scratch awl is a woodworking layout and point-making tool. It is used to scribe a line to be followed by a hand saw or chisel when making woodworking joints and other operations. The scratch awl is basically a steel spike with its tip sharpen ...
, and nails.Wang (1982), 122. Common iron commodities found in Han dynasty homes included tripods,
stove A stove or range is a device that burns fuel or uses electricity to generate heat inside or on top of the apparatus, to be used for general warming or cooking. It has evolved highly over time, with cast-iron and induction versions being develope ...
s, cooking pots,
belt buckle A belt buckle is a buckle, a clasp for fastening two ends, such as of straps or a belt, in which a device attached to one of the ends is fitted or coupled to the other. The word enters Middle English via Old French and the Latin ''buccula' ...
s,
tweezers Tweezers are small hand tools used for grasping objects too small to be easily handled with the human fingers. Tweezers are thumb-driven forceps most likely derived from tongs used to grab or hold hot objects since the dawn of recorded history. ...
, fire
tongs Tongs are a type of tool used to grip and lift objects instead of holding them directly with hands. There are many forms of tongs adapted to their specific use. The first pair of tongs belongs to the Egyptians. Tongs likely started off as b ...
,
scissors Scissors are hand-operated shearing tools. A pair of scissors consists of a pair of metal blades pivoted so that the sharpened edges slide against each other when the handles (bows) opposite to the pivot are closed. Scissors are used for cutti ...
, kitchen knives,
fish hook A fish hook or fishhook, formerly also called angle (from Old English ''angol'' and Proto-Germanic ''*angulaz''), is a hook used to catch fish either by piercing and embedding onto the inside of the fish mouth (angling) or, more rarely, by impa ...
s, and needles.
Mirrors A mirror or looking glass is an object that Reflection (physics), reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the ...
and
oil lamp An oil lamp is a lamp used to produce light continuously for a period of time using an oil-based fuel source. The use of oil lamps began thousands of years ago and continues to this day, although their use is less common in modern times. Th ...
s were often made of either bronze or iron. Coin money minted during the Han was made of either
copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
or copper and
tin Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal. Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...
smelted together to make the bronze alloy.


Agriculture


Tools and methods

Modern archaeologists have unearthed Han iron farming tools throughout China, from
Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an autonomous region of the People's Republic of China. Its border includes most of the length of China's border with the country of Mongolia. Inner Mongolia also accounts for a ...
in the north to
Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...
in the south.Wang (1982), 53. The spade, shovel, pick, and
plow A plough or plow ( US; both ) is a farm tool for loosening or turning the soil before sowing seed or planting. Ploughs were traditionally drawn by oxen and horses, but in modern farms are drawn by tractors. A plough may have a wooden, iron or ...
were used for
tillage Tillage is the agricultural preparation of soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shoveling, picking, mattock work, hoein ...
, the hoe for
weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...
ing, the rake for loosening the soil, and the
sickle A sickle, bagging hook, reaping-hook or grasshook is a single-handed agricultural tool designed with variously curved blades and typically used for harvesting, or reaping, grain crops or cutting succulent forage chiefly for feeding livestock, ei ...
for harvesting crops. Depending on their size, Han plows were driven by either one ox or two oxen.Wang (1982), 54. Oxen were also used to pull the three-legged iron
seed drill A seed drill is a device used in agriculture that sows seeds for crops by positioning them in the soil and burying them to a specific depth while being dragged by a tractor. This ensures that seeds will be distributed evenly. The seed drill sow ...
(invented in Han China by the 2nd century BCE), which enabled farmers to plant seeds in precise rows instead of casting them out by hand. While artwork of the Wei (220–266 CE) and Jin (266–420) periods show use of the harrow for breaking up chunks of soil after plowing, it perhaps first appeared in China during the Eastern Han (25–220 CE).Wang (1982), 55.
Irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...
works for agriculture included the use of
water well A well is an excavation or structure created in the ground by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. Th ...
s, artificial ponds and embankments,
dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...
s,
canal Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface flow un ...
s, and
sluice Sluice ( ) is a word for a channel controlled at its head by a movable gate which is called a sluice gate. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway and can be considered ...
gates.


Alternating fields

During Emperor Wu's (r. 141–87 BCE) reign, the Grain Intendant Zhao Guo (趙過) invented the alternating fields system (''daitianfa'' 代田法).Nishijima (1986), 561. For every ''mou'' of land—i.e. a thin but elongated strip of land measuring wide and long, or an area of roughly —three low-lying
furrows A plough or plow ( US; both ) is a farm tool for loosening or turning the soil before sowing seed or planting. Ploughs were traditionally drawn by oxen and horses, but in modern farms are drawn by tractors. A plough may have a wooden, iron or ...
(''quan'' 甽) that were each wide were sowed in straight lines with crop seed. While weeding in the summer, the loose soil of the
ridges A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...
(''long'' 壟) on either side of the furrows would gradually fall into the furrows, covering the sprouting crops and protecting them from wind and drought. Since the position of the furrows and ridges were reversed by the next year, this process was called the alternating fields system. This system allowed crops to grow in straight lines from sowing to harvest, conserved moisture in the soil, and provided a stable annual yield for harvested crops.Nishijima (1986), 562. Zhao Guo first experimented with this system right outside the capital
Chang'an Chang'an (; ) is the traditional name of Xi'an. The site had been settled since Neolithic times, during which the Yangshao culture was established in Banpo, in the city's suburbs. Furthermore, in the northern vicinity of modern Xi'an, Qin Shi ...
, and once it proved successful, he sent out instructions for it to every
commandery In the Middle Ages, a commandery (rarely commandry) was the smallest administrative division of the European landed properties of a military order. It was also the name of the house where the knights of the commandery lived.Anthony Luttrell and G ...
administrator, who were then responsible for disseminating these to the heads of every
county A county is a geographic region of a country used for administrative or other purposesChambers Dictionary, L. Brookes (ed.), 2005, Chambers Harrap Publishers Ltd, Edinburgh in certain modern nations. The term is derived from the Old French ...
,
district A district is a type of administrative division that, in some countries, is managed by the local government. Across the world, areas known as "districts" vary greatly in size, spanning regions or counties, several municipalities, subdivisions o ...
, and
hamlet ''The Tragedy of Hamlet, Prince of Denmark'', often shortened to ''Hamlet'' (), is a tragedy written by William Shakespeare sometime between 1599 and 1601. It is Shakespeare's longest play, with 29,551 words. Set in Denmark, the play depicts ...
in their commanderies. Sadao Nishijima speculates that the Imperial Counselor
Sang Hongyang Sang Hongyang (Chinese: ; c. 152–80 BC) was a Chinese politician. He was a prominent official of the Han Dynasty, who served Emperor Wu of Han and his successor Emperor Zhao. He is famous for his economic policies during the reign of Emperor ...
(d. 80 BCE) perhaps had a role in promoting this new system. Rich families who owned oxen and large heavy moldboard iron plows greatly benefited from this new system. However, poorer farmers who did not own oxen resorted to using teams of men to move a single plow, which was exhausting work.Nishijima (1986), 563–564. The author Cui Shi (催寔) (d. 170 CE) wrote in his ''Simin yueling'' (四民月令) that by the Eastern Han Era (25–220 CE) an improved plow was invented which needed only one man to control it, two oxen to pull it, had three plowshares, a seed box for the drills, a tool which turned down the soil, and could sow roughly of land in a single day.


Pit fields

During the reign of
Emperor Cheng of Han Emperor Cheng of Han (51 BC – 17 April 7 BC) was an emperor of the Chinese Han dynasty ruling from 33 until 7 BC. He succeeded his father Emperor Yuan of Han. Under Emperor Cheng, the Han dynasty continued its growing disintegration as the emp ...
(r. 33–37 BCE), Fan Shengzhi wrote a manual (i.e. the ''
Fan Shengzhi shu ''Fan Shengzhi shu'' ("Fan Shengzhi's book" or "Fan Shengzhi's manual") was a Chinese agricultural text from the Han dynasty, written by Fan Shengzhi in the first century BC. The book was lost in the 11th- or 12th-century Song dynasty, possibly dur ...
'') which described the pit field system (''aotian'' 凹田).Nishijima (1986), 564–565.Hinsch (2002), 67–68. In this system, every ''mou'' of farmland was divided into 3,840 grids which each had a small pit that was dug deep and wide and had good quality
manure Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutri ...
mixed into the soil. Twenty seeds were sowed into each pit, which allegedly produced 0.6 L (20 oz) of harvested grain per pit, or roughly 2,000 L (67,630 oz) per ''mou''. This system did not require oxen-driven plows or the most fertile land, since it could be employed even on sloping terrains where supplying water was difficult for other methods of farming. Although this farming method was favored by the poor, it did require intensive labor, thus only large families could maintain such a system.


Rice paddies

Han farmers in the
Yangzi River The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows ...
region of southern China often maintained
paddy field A paddy field is a flooded field (agriculture), field of arable land used for growing Aquatic plant, semiaquatic crops, most notably rice and taro. It originates from the Neolithic rice-farming cultures of the Yangtze River basin in sout ...
s for growing
rice Rice is the seed of the grass species ''Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima ''Oryza glaberrima'', commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown i ...
. Every year, they would burn the weeds in the paddy field, drench it in water, sow rice by hand, and around harvest time cut the surviving weeds and drown them a second time.Nishijima (1986), 568–569. In this system, the field lays
fallow Fallow is a farming technique in which arable land is left without sowing for one or more vegetative cycles. The goal of fallowing is to allow the land to recover and store organic matter while retaining moisture and disrupting pest life cycles ...
for much of the year and thus did not remain very fertile. However, Han rice farmers to the north around the
Huai River The Huai River (), Postal Map Romanization, formerly romanization of Chinese, romanized as the Hwai, is a major river in China. It is located about midway between the Yellow River and Yangtze, the two longest rivers and largest drainage basins ...
practiced the more advanced system of transplantation.Nishijima (1986), 570–572. In this system, individual plants were given intensive care (perhaps in the same location as the paddy field), their offshoots separated so that more water could be conserved, and the field could be heavily fertilized since winter crops were grown while the rice seedlings were situated nearby in a plant nursery.


Mechanical and hydraulic engineering


Literary sources and archaeological evidence

Evidence of Han-era mechanical engineering comes largely from the choice observational writings of sometimes disinterested Confucian scholars. Professional artisan-engineers (''jiang'' 匠) did not leave behind detailed records of their work. Han scholars, who often had little or no expertise in mechanical engineering, sometimes provided insufficient information on the various technologies they described. Nevertheless, some Han literary sources provide crucial information. As written by Yang Xiong in 15 BCE, the
belt drive A belt is a loop of flexible material used to link two or more rotating shafts mechanically, most often parallel. Belts may be used as a source of motion, to transmit power efficiently or to track relative movement. Belts are looped over pulley ...
was first used for a
quilling Quilling is an art form that involves the use of strips of paper that are rolled, shaped, and glued together to create decorative designs. The paper is rolled, looped, curled, twisted, and otherwise manipulated to create shapes that make up d ...
device which wound silk fibers onto the
bobbin A bobbin or spool is a spindle or cylinder, with or without flanges, on which yarn, thread, wire, tape or film is wound. Bobbins are typically found in industrial textile machinery, as well as in sewing machines, fishing reels, tape measure ...
s of weaver shuttles.Temple (1986), 54–55. The invention of the belt drive was a crucial first step in the development of later technologies during the Song dynasty, such as the
chain drive Chain drive is a way of transmitting mechanical power from one place to another. It is often used to convey power to the wheels of a vehicle, particularly bicycles and motorcycles. It is also used in a wide variety of machines besides vehicles. ...
and
spinning wheel A spinning wheel is a device for spinning thread or yarn from fibres. It was fundamental to the cotton textile industry prior to the Industrial Revolution. It laid the foundations for later machinery such as the spinning jenny and spinning f ...
. The inventions of the artisan and mechanical engineer Ding Huan (丁緩) are mentioned in the ''Miscellaneous Notes on the Western Capital''. The official and poet
Sima Xiangru Sima Xiangru ( , ; c. 179117BC) was a Chinese musician, poet, and politician who lived during the Western Han dynasty. Sima is a significant figure in the history of Classical Chinese poetry, and is generally regarded as the greatest of all com ...
(179–117 BCE) once hinted in his writings that the Chinese used a
censer A censer, incense burner, perfume burner or pastille burner is a vessel made for burning incense or perfume in some solid form. They vary greatly in size, form, and material of construction, and have been in use since ancient times throughout t ...
in the form of a
gimbal A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of ...
, a pivot support made of concentric rings which allow the central gimbal to rotate on an axis while remaining vertically positioned.Needham (1986c), 233–234. However, the first explicit mention of the gimbal used as an incense burner occurred around 180 CE when the artisan Ding Huan created his 'Perfume Burner for use among Cushions' which allowed burning incense placed within the central gimbal to remain constantly level even when moved. Ding had other inventions as well. For the purpose of indoor
air conditioning Air conditioning, often abbreviated as A/C or AC, is the process of removing heat from an enclosed space to achieve a more comfortable interior environment (sometimes referred to as 'comfort cooling') and in some cases also strictly controlling ...
, he set up a large manually operated rotary fan which had rotating wheels that were in diameter. He also invented a lamp which he called the 'nine-storied hill-censer', since it was shaped as a hillside.Temple (1986), 87; Needham (1986b), 123. When the cylindrical lamp was lit, the
convection Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...
of rising hot air currents caused vanes placed on the top to spin, which in turn rotated painted paper figures of birds and other animals around the lamp. When
Emperor Gaozu of Han Emperor Gaozu of Han (256 – 1 June 195 BC), born Liu Bang () with courtesy name Ji (季), was the founder and first emperor of the Han dynasty, reigning in 202–195 BC. His temple name was "Taizu" while his posthumous name was Emper ...
(r. 202–195 BCE) came upon the treasury of
Qin Shi Huang Qin Shi Huang (, ; 259–210 BC) was the founder of the Qin dynasty and the first emperor of a unified China. Rather than maintain the title of "king" ( ''wáng'') borne by the previous Shang and Zhou rulers, he ruled as the First Emperor ( ...
(r. 221–210) at
Xianyang Xianyang () is a prefecture-level city in central Shaanxi province, situated on the Wei River a few kilometers upstream (west) from the provincial capital of Xi'an. Once the capital of the Qin dynasty, it is now integrated into the Xi'an metrop ...
following the downfall of the
Qin dynasty The Qin dynasty ( ; zh, c=秦朝, p=Qín cháo, w=), or Ch'in dynasty in Wade–Giles romanization ( zh, c=, p=, w=Ch'in ch'ao), was the first Dynasties in Chinese history, dynasty of Imperial China. Named for its heartland in Qin (state), ...
(221–206), he found an entire miniature musical orchestra of
puppet A puppet is an object, often resembling a human, animal or Legendary creature, mythical figure, that is animated or manipulated by a person called a puppeteer. The puppeteer uses movements of their hands, arms, or control devices such as rods ...
s tall who played
mouth organs A mouth organ is any free reed aerophone with one or more air chambers fitted with a free reed. Though it spans many traditions, it is played universally the same way by the musician placing their lips over a chamber or holes in the instrument, an ...
if one pulled on ropes and blew into tubes to control them.Needham (1986c), 158. Zhang Heng wrote in the 2nd century CE that people could be entertained by theatrical plays of artificial fish and dragons. Later, the inventor Ma Jun ( fl. 220–265) invented a theater of moving mechanical puppets powered by the rotation of a hidden waterwheel. From literary sources it is known that the collapsible umbrella was invented during Wang Mang's reign, although the simple parasol existed beforehand. This employed sliding levers and bendable joints that could be protracted and retracted. Modern archaeology has led to the discovery of Han artwork portraying inventions which were otherwise absent in Han literary sources. This includes the crank handle. Han pottery tomb models of farmyards and
gristmill A gristmill (also: grist mill, corn mill, flour mill, feed mill or feedmill) grinds cereal grain into flour and Wheat middlings, middlings. The term can refer to either the Mill (grinding), grinding mechanism or the building that holds it. Grist i ...
s possess the first known depictions of crank handles, which were used to operate the fans of winnowing machines.Needham (1986c), 116–119, 153–154 & Plate CLVI; Temple (1986), 46; Wang (1982), 57. The machine was used to separate
chaff Chaff (; ) is the dry, scaly protective casing of the seeds of cereal grains or similar fine, dry, scaly plant material (such as scaly parts of flowers or finely chopped straw). Chaff is indigestible by humans, but livestock can eat it. In agri ...
from grain, but the Chinese of later dynasties also employed the crank handle for silk-reeling, hemp-spinning, flour-sifting, and drawing water from a well using the
windlass The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound arou ...
. To measure distance traveled, the Han-era Chinese also created the
odometer An odometer or odograph is an instrument used for measuring the distance traveled by a vehicle, such as a bicycle or car. The device may be electronic, mechanical, or a combination of the two (electromechanical). The noun derives from ancient Gr ...
cart. This invention is depicted in Han artwork by the 2nd century CE, yet detailed written descriptions were not offered until the 3rd century. The wheels of this device rotated a set of gears which in turn forced mechanical figures to bang gongs and drums that alerted the travelers of the distance traveled (measured in '' li''). From existing specimens found at archaeological sites, it is known that Han-era craftsmen made use of the sliding metal
caliper A caliper (British spelling also calliper, or in plurale tantum sense a pair of calipers) is a device used to measure the dimensions of an object. Many types of calipers permit reading out a measurement on a ruled scale, a dial, or a digital dis ...
to make minute measurements. Although Han-era calipers bear incised inscriptions of the exact day of the year they were manufactured, they are not mentioned in any Han literary sources.


Uses of the waterwheel and water clock

By the Han dynasty, the Chinese developed various uses for the
waterwheel A water wheel is a machine for converting the energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a wheel (usually constructed from wood or metal), with a number of blades or buckets ...
. An improvement of the simple
lever A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or ''fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is div ...
-and-
fulcrum A fulcrum is the support about which a lever pivots. Fulcrum may also refer to: Companies and organizations * Fulcrum (Anglican think tank), a Church of England think tank * Fulcrum Press, a British publisher of poetry * Fulcrum Wheels, a bicy ...
tilt hammer device operated by one's foot, the hydraulic-powered
trip hammer A trip hammer, also known as a tilt hammer or helve hammer, is a massive powered hammer. Traditional uses of trip hammers include pounding, decorticating and polishing of grain in agriculture. In mining, trip hammers were used for crushing meta ...
used for pounding, decorticating, and polishing grain was first mentioned in the Han dictionary ''
Jijiupian The ''Jijiupian'' is a Chinese character primer that was compiled by the Han dynasty scholar Shi You around 40 BCE. Similar to an abecedarium, it contains a series of orthographic word lists, categorized according to character radical, and brief ...
'' of 40 BCE.Needham (1986c), 183–184, 390–392. It was also mentioned in the '' Regional Speech'' (''Fangyan'') dictionary written by Yang Xiong (53 BCE – 18 CE) in 15 BCE, the philosophical ''Xinlun'' 新論 written by
Huan Tan Huan Tan (BC– AD28) was a Chinese philosopher, poet, and politician of the Western Han and its short-lived interregnum between AD9 and 23, known as the Xin Dynasty. Life Huan worked as an official under the administrations of Emperor Ai of ...
(43 BCE – 28 CE) in 20 CE, the poetry of Ma Rong (79–166 CE), and the writings of
Kong Rong Kong Rong () (153 – 26 September 208), courtesy name Wenju, was a Chinese poet, politician, and minor warlord. who lived during the late Eastern Han dynasty of China. He was a 20th generation descendant of Confucius. As he was once the Chance ...
(153–208 CE). In his '' Balanced Discourse'' (''Lunheng''), the philosopher
Wang Chong Wang Chong (; 27 – c. 97 AD), courtesy name Zhongren (仲任), was a Chinese astronomer, meteorologist, naturalist, philosopher, and writer active during the Han Dynasty. He developed a rational, secular, naturalistic and mechanistic account ...
(27–100 CE) was the first in China to describe the square-pallet
chain pump The chain pump is type of a water pump in which several circular discs are positioned on an endless chain. One part of the chain dips into the water, and the chain runs through a tube, slightly bigger than the diameter of the discs. As the chain is ...
used to lift water (and other substances).Needham (1986c), 89, 110, & 344. Although some models were operated manually by foot pedals, some chain pumps were powered by a horizontal waterwheel which rotated large toothed gears and a horizontal axis beam.Needham (1986c), 342–346. Their primary use was for lifting water into irrigation ditches, but chain pumps were also used in
public works Public works are a broad category of infrastructure projects, financed and constructed by the government, for recreational, employment, and health and safety uses in the greater community. They include public buildings ( municipal buildings, sc ...
programs, such as when
Zhang Rang The Ten Attendants, also known as the Ten Eunuchs, were a group of influential eunuch-officials in the imperial court of Emperor Ling ( 168–189) in Eastern Han China. Although they are often referred to as a group of 10, there were actually 12 ...
(d. 189) had an engineer build several of them to lift water into pipes that provided the capital
Luoyang Luoyang is a city located in the confluence area of Luo River (Henan), Luo River and Yellow River in the west of Henan province. Governed as a prefecture-level city, it borders the provincial capital of Zhengzhou to the east, Pingdingshan to the ...
and its palaces with clean water. While acting as administrator of
Nanyang Nanyang is the romanization of two common Chinese place names. It may refer to: Written as 南洋 (Southern Ocean) * Nanyang (region), a Chinese term denoting the Southeast Asian lands surrounding the South China Sea ;China * Nanyang Fleet, Qing ...
in 31 CE,
Du Shi Du Shi (, d. 38'' Book of Later Han'', vol. 31Crespigny, 183.) was a Chinese hydrologist, inventor, mechanical engineer, metallurgist, and politician of the Eastern Han Dynasty. Du Shi is credited with being the first to apply hydraulic power (i ...
(d. 38) invented a water-powered reciprocator which worked the bellows of the blast furnace and cupola furnace in smelting iron; before this invention, intensive manual labor was required to work the bellows. Although the astronomical
armillary sphere An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of ...
(representing the
celestial sphere In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, ...
) had existed in China since the 1st century BCE, the mathematician and court astronomer
Zhang Heng Zhang Heng (; AD 78–139), formerly romanized as Chang Heng, was a Chinese polymathic scientist and statesman who lived during the Han dynasty. Educated in the capital cities of Luoyang and Chang'an, he achieved success as an astronomer, ma ...
(78–139 CE) provided it with motive power by using the constant
pressure head In fluid mechanics, pressure head is the height of a liquid column that corresponds to a particular pressure exerted by the liquid column on the base of its container. It may also be called static pressure head or simply static head (but not ''sta ...
of an inflow
water clock A water clock or clepsydra (; ; ) is a timepiece by which time is measured by the regulated flow of liquid into (inflow type) or out from (outflow type) a vessel, and where the amount is then measured. Water clocks are one of the oldest time-m ...
to rotate a waterwheel that acted on a set of
gear A gear is a rotating circular machine part having cut teeth or, in the case of a cogwheel or gearwheel, inserted teeth (called ''cogs''), which mesh with another (compatible) toothed part to transmit (convert) torque and speed. The basic pr ...
s. Zhang Heng was also the first to address the problem of the falling pressure head in the inflow water clock (which gradually slowed the
timekeeping Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to co ...
) by setting up an additional tank between the reservoir and inflow vessel.


Seismometer

The Han court was responsible for the major efforts of disaster relief when natural disasters such as
earthquake An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
s devastated the lives of commoners.Ebrey (1986), 621. To better prepare for calamities, Zhang Heng invented a
seismometer A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The outpu ...
in 132 CE, which provided instant alert to authorities in the capital Luoyang that an earthquake had occurred in a location indicated by a specific cardinal or ordinal direction. Although no tremors could be felt in the capital when Zhang told the court that an earthquake had just occurred in the northwest, a message came soon afterwards that an earthquake had indeed struck northwest of Luoyang (in what is now modern
Gansu Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibet ...
). Zhang called his device the 'instrument for measuring the seasonal winds and the movements of the Earth' (Houfeng didong yi 候风地动仪), so-named because he and others thought that earthquakes were most likely caused by the enormous compression of trapped air.Needham (1986a), 626. As described in the ''
Book of the Later Han The ''Book of the Later Han'', also known as the ''History of the Later Han'' and by its Chinese name ''Hou Hanshu'' (), is one of the Twenty-Four Histories and covers the history of the Han dynasty from 6 to 189 CE, a period known as the Later ...
'', the frame of the seismometer was a domed bronze vessel in the shape of a wine jar, although it was in diameter and decorated with scenes of mountains and animals. The trigger mechanism was an
inverted pendulum An inverted pendulum is a pendulum that has its center of mass above its pivot point. It is unstable and without additional help will fall over. It can be suspended stably in this inverted position by using a control system to monitor the angle ...
(which the ''Book of the Later Han'' calls the "central column") that, if disturbed by the ground tremors of earthquakes located near or far away, would swing and strike one of eight mobile arms (representing the eight directions), each with a crank and catch mechanism. The crank and a right angle lever would raise one of eight metal dragon heads located on the exterior, dislodging a metal ball from its mouth that dropped into the mouth of one of eight metal toads below arranged like the points on a
compass rose A compass rose, sometimes called a wind rose, rose of the winds or compass star, is a figure on a compass, map, nautical chart, or monument used to display the orientation of the cardinal directions (north, east, south, and west) and their int ...
, thus indicating the direction of the earthquake.Needham (1986a), 627–631. The ''Book of the Later Han'' states that when the ball fell into any one of eight toad mouths, it produced a loud noise which gained the attention of those observing the device.Needham (1986a), 626–627. While Wang Zhenduo (王振铎) accepted the idea that Zhang's seismometer had cranks and levers which were disturbed by the inverted pendulum, his contemporary Akitsune Imamura (1870–1948) argued that the inverted pendulum could have had a pin at the top which, upon moving by force of the ground vibrations, would enter one of eight slots and expel the ball by pushing a slider.Needham (1986a), 631. Since the ''Book of the Later Han'' states that the other seven dragon heads would not subsequently release the balls lodged up into their jaws after the first one had dropped, Imamura asserted that the pin of the pendulum would have been locked into the slot it had entered and thus immobilized the instrument until it was reset.


Mathematics and astronomy


Mathematical treatises

One of the earliest surviving mathematical treatises of ancient China is the ''
Book on Numbers and Computation The ''Book on Numbers and Computation'' (), or the ''Writings on Reckoning'', is one of the earliest known Chinese mathematical treatises. It was written during the early Western Han dynasty, sometime between 202 BC and 186 BC.Liu et al. (2003), ...
'' (''Suan shu shu''), part of the
Zhangjiashan Han bamboo texts The Zhangjiashan Han bamboo texts are ancient Han Dynasty Chinese written works dated 196–186 BC. They were discovered in 1983 by archaeologists excavating tomb no. 247 at Mount Zhangjia () of Jiangling County, Hubei Province (near modern Jing ...
dated 202 to 186 BCE and found in
Jiangling County Jiangling () is a county in southern Hubei province, People's Republic of China. Administratively, it is under the jurisdiction of Jingzhou City. History The county name derived from the old name of Jingzhou. Liang dynasty Prince Xiao Yi 蕭繹 ( ...
,
Hubei Hubei (; ; alternately Hupeh) is a landlocked province of the People's Republic of China, and is part of the Central China region. The name of the province means "north of the lake", referring to its position north of Dongting Lake. The prov ...
. Another mathematical text compiled during the Han was ''The Arithmetical Classic of the Gnomon and the Circular Paths of Heaven'' (''Zhoubi Suanjing''), dated no earlier than the 1st century BCE (from perhaps multiple authors) and contained materials similar to those described by Yang Xiong in 15 BCE, yet the ''zhoubi'' school of mathematics was not explicitly mentioned until
Cai Yong Cai Yong (Chinese: ; 132–192), courtesy name Bojie, was Chinese astronomer, calligrapher, historian, mathematician, musician, politician, and writer of the Eastern Han dynasty. He was well-versed in calligraphy, music, mathematics and astrono ...
's (132–192 CE) commentary of 180. A preface was added to the text by Zhao Shuang 趙爽 in the 3rd century.Dauben (2007), 214. There was also the ''
Nine Chapters on the Mathematical Art ''The Nine Chapters on the Mathematical Art'' () is a Chinese mathematics book, composed by several generations of scholars from the 10th–2nd century BCE, its latest stage being from the 2nd century CE. This book is one of the earliest sur ...
'' (''Jiuzhang Suanshu''); its full title was found on two bronze standard measurers dated 179 CE (with speculation that its material existed in earlier books under different titles) and was provided with detailed commentary by
Liu Hui Liu Hui () was a Chinese mathematician who published a commentary in 263 CE on ''Jiu Zhang Suan Shu (The Nine Chapters on the Mathematical Art).'' He was a descendant of the Marquis of Zixiang of the Eastern Han dynasty and lived in the state o ...
(fl. 3rd century) in 263.Needham (1986a), 24–25. It is worth noting in this context that many of the documents excavated from Qin and Han sites contain evidence of the practical mathematics used by administrators for inventories and taxes, as well as for calculating labor needed for public works projects, just as described in the mathematical treatises.


Innovations in the treatises

The ''Suan shu shu'' presents basic mathematics problems and solutions. It was most likely a handbook for day-to-day business transactions or affairs of government administration.Dauben (2007), 213. It contains problems and solutions for field measurements of
area Area is the quantity that expresses the extent of a region on the plane or on a curved surface. The area of a plane region or ''plane area'' refers to the area of a shape A shape or figure is a graphics, graphical representation of an obje ...
, proportional
exchange rate In finance, an exchange rate is the rate at which one currency will be exchanged for another currency. Currencies are most commonly national currencies, but may be sub-national as in the case of Hong Kong or supra-national as in the case of ...
s for agricultural
millet Millets () are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food. Most species generally referred to as millets belong to the tribe Paniceae, but some millets al ...
and
rice Rice is the seed of the grass species ''Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima ''Oryza glaberrima'', commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown i ...
, distribution by
proportion Proportionality, proportion or proportional may refer to: Mathematics * Proportionality (mathematics), the property of two variables being in a multiplicative relation to a constant * Ratio, of one quantity to another, especially of a part compare ...
, short width division, and excess and deficiency.Dauben (2007), 212. Some of the problems found in the ''Suan shu shu'' appear in the later text ''Jiuzhang suanshu''; in five cases, the titles are exact matches. However, unlike the ''Jiuzhang suanshu'', the ''Suan shu shu'' does not deal with problems involving right-angle triangles,
square root In mathematics, a square root of a number is a number such that ; in other words, a number whose ''square'' (the result of multiplying the number by itself, or  ⋅ ) is . For example, 4 and −4 are square roots of 16, because . E ...
s,
cube root In mathematics, a cube root of a number is a number such that . All nonzero real numbers, have exactly one real cube root and a pair of complex conjugate cube roots, and all nonzero complex numbers have three distinct complex cube roots. Fo ...
s, and
matrix methods The matrix method is a structural analysis method used as a fundamental principle in many applications in civil engineering. The method is carried out, using either a stiffness matrix or a flexibility matrix. See also * Direct stiffness method A ...
, which demonstrates the significant advancements made in Chinese mathematics between the writings of these two texts. The ''Zhoubi suanjing'', written in dialogue form and with regularly presented problems, is concerned with the application of mathematics to
astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
. In one problem which sought to determine the height of the
Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
from the
Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
and the
diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...
of the Sun, Chen Zi (陳子) instructs Rong Fang (榮方) to wait until the shadow cast by the 8 ''chi'' tall
gnomon A gnomon (; ) is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields. History A painted stick dating from 2300 BC that was excavated at the astronomical site of Taosi is the ol ...
is 6 ''Chinese units of measurement, chi'' (one ''chi'' during the Han was 33 cm), so that a 3-4-5 right-angle triangle can be constructed where the base is Li (unit), 60,000 ''li'' (one ''li'' during the Han was the equivalent of 415 m or 1362 ft), the hypotenuse leading towards the sun is 100,000 ''li'', and the height of the sun is 80,000 ''li''.Dauben (2007), 219. Like the ''Jiuzhang suanshu'', the ''Zhoubi suanjing'' also gives mathematical proof for the "Gougu Theorem" (勾股定理; i.e. where ''c'' is the length of the hypotenuse and ''a'' and ''b'' are the lengths of the other two sides, respectively, a2 + b2 = c2), which is known as the
Pythagorean theorem In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse (the side opposite t ...
in the West after the Greek mathematician Pythagoras (fl. 6th century BCE). The ''Jiuzhang suanshu'' was perhaps the most groundbreaking of the three surviving Han treatises. It is the first known book to feature
negative number In mathematics, a negative number represents an opposite. In the real number system, a negative number is a number that is less than zero. Negative numbers are often used to represent the magnitude of a loss or deficiency. A debt that is owed m ...
s, along with the Bakhshali manuscript (200? – 600? CE) of India and the book of Greek mathematics, the Greek mathematician Diophantus (fl. 3rd century) written in about 275 CE. Negative numbers appeared as Counting rods, black counting rods, while positive numbers appeared as Counting rods, red counting rods. Although the decimal system existed in China since the Shang dynasty (c. 1600 – c. 1050 BCE), the earliest evidence of a Fraction (mathematics), decimal fraction (i.e. the denominator Exponentiation, is a power of ten) is an inscription on a standard volume-measuring vessel dated 5 CE and used by the mathematician and astronomer Liu Xin (scholar), Liu Xin (46 BCE – 23 CE).Temple (1986), 139 & 142–143. Yet the first book to feature decimal fractions was the ''Jiuzhang suanshu'', as a means to solve equations and represent measurements.
Gaussian elimination In mathematics, Gaussian elimination, also known as row reduction, is an algorithm for solving systems of linear equations. It consists of a sequence of operations performed on the corresponding matrix of coefficients. This method can also be used ...
, an algorithm used to solve System of linear equations, linear equations, was known as the Array Rule in the ''Jiuzhang suanshu''. While the book used continued fractions to find the root of a function, roots of equations, Liu Hui built on this idea in the 3rd century when he increased the decimals to find the cube root of 1,860,867 (yielding the answer 123), the same method used in the
Horner scheme In mathematics and computer science, Horner's method (or Horner's scheme) is an algorithm for polynomial evaluation. Although named after William George Horner, this method is much older, as it has been attributed to Joseph-Louis Lagrange by Hor ...
named after William George Horner (1786–1837).Temple (1986), 142.


Approximations of pi

For centuries, the Chinese had simply approximated the value of pi as 3, until Liu Xin approximated it at 3.154 sometime between 1–5 CE, although the method he used to reach this value is unknown to historians.Needham (1986a), 99–100. Standard measuring vessels dating to the reign of
Wang Mang Wang Mang () (c. 45 – 6 October 23 CE), courtesy name Jujun (), was the founder and the only Emperor of China, emperor of the short-lived Chinese Xin dynasty. He was originally an official and consort kin of the Han dynasty and later ...
(9–23 CE) also showed Approximations of π, approximations for pi at 3.1590, 3.1497, and 3.167.Berggren, Borwein & Borwein (2004), 27. Zhang Heng is the next known Han mathematician to have made an approximation for pi. Han mathematicians understood that the area of a square versus the area of its inscribed circle had an approximate ratio of 4:3, and also understood that the volume of a cube and the volume of its inscribed sphere would be 42:32. With ''D'' as
diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...
and ''V'' as volume, D3:V = 16:9 or V=916D3, a formula Zhang found fault with since he realized the value for diameter was inaccurate, the discrepancy being the value taken for the ratio. To fix this, Zhang added 116D3 to the formula, thus V = 916D3 + 116D3 = 58D3. Since he found the ratio of the volume of the cube to the inscribed sphere at 8:5, the ratio of the area of a square to the inscribed circle is :. With this formula, Zhang was able to approximate pi as the
square root In mathematics, a square root of a number is a number such that ; in other words, a number whose ''square'' (the result of multiplying the number by itself, or  ⋅ ) is . For example, 4 and −4 are square roots of 16, because . E ...
of 10, or 3.162. After the Han, Liu Hui's pi algorithm, Liu Hui approximated pi as 3.14159, while the mathematician Zu Chongzhi (429–500) Milü, approximated pi at 3.141592 (or 355113), the most accurate approximation the ancient Chinese would achieve.


Musical tuning and theory

Mathematics were also used in musical tuning and music theory. The 2nd-century-BCE ''Huainanzi'', compiled by Eight Immortals of Huainan, eight scholars under the patronage of King Liu An (179–122 BCE), outlined the use of Chromatic scale, twelve tones on a musical scale.McClain & Ming (1979), 207–208. Jing Fang (78–37 BCE), a mathematician and music theorist, expanded these to create a scale of 60 tones. While doing so, Jing Fang realized that 53 just fifths is approximate to 31 octaves.McClain & Ming (1979), 212; Needham (1986b), 218–219. By calculating the difference at 177147176776, Jing reached the same value of 53 equal temperament duly discovered by the German mathematician Nicholas Mercator (1620–1687) (i.e. 353/284, known as Mercator's comma). Later, the prince Zhu Zaiyu (1536–1611) in Ming dynasty, Ming China and Simon Stevin (1548–1620) of the Flemish Region in Europe would simultaneously (but separately) discover the mathematical formula for equal temperament.


Astronomical observations

The ancient Chinese made careful observations of heavenly bodies and phenomena since observations of the cosmos were used for astrology and prognostication. The astronomer Gan De (fl. 4th century BCE) from the Qi (state), State of Qi was the first in history to acknowledge sunspots as genuine solar phenomena (and not obstructing natural satellites as thought in the West after Einhard's observation in 807), while the first precisely dated sunspot observation in China occurred on May 10, 28 BCE, during the reign of
Emperor Cheng of Han Emperor Cheng of Han (51 BC – 17 April 7 BC) was an emperor of the Chinese Han dynasty ruling from 33 until 7 BC. He succeeded his father Emperor Yuan of Han. Under Emperor Cheng, the Han dynasty continued its growing disintegration as the emp ...
(r. 33–7 BCE). Among the Mawangdui Silk Texts dated no later than 168 BCE (when they were sealed in a tomb at Mawangdui, Mawangdui Han tombs site, Changsha,
Hunan Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi to ...
province), the ''Miscellaneous Readings of Cosmic Patterns and Pneuma Images'' (''Tianwen qixiang zazhan'' 天文氣象雜占) manuscript illustrates in writings and ink drawings roughly 300 different climatic and astronomical features, including clouds, mirages, rainbows, stars, constellations, and comets. Another silk text from the same site reports the times and locations of the rising and setting of planets in the night sky from the years 246–177 BCE. The Han-era Chinese noted the passage of the same comet seen in Persia for the birth of Mithridates II of Parthia in 135 BCE, Caesar's Comet, the same comet Ancient Rome, the Romans observed close to the assassination of Julius Caesar in 44 BCE, Halley's comet in 12 BCE, the same comet noted by Roman historian Cassius Dio (c. 155 – c. 229 CE) for 13 CE, and (what is now known to have been) a supernova in AD 185.Loewe (1994), 69. For various comets discussed in the Han-era history books ''Records of the Grand Historian'' and ''Book of Han'', details are given for their position in the sky and direction they were moving, the length of time they were visible, their color, and their size. The Han-era Chinese also made star catalogues, such as historian Sima Qian's (145–86 BCE) ''A Monograph on Celestial Officials'' (''Tianguanshu'' 天官書) and Zhang Heng's 2nd-century-CE star catalogue which featured roughly 2,500 stars and 124 constellations. To create a three-dimensional representation of such observations, Astronomer Geng Shouchang (耿壽昌) provided his
armillary sphere An armillary sphere (variations are known as spherical astrolabe, armilla, or armil) is a model of objects in the sky (on the celestial sphere), consisting of a spherical framework of rings, centered on Earth or the Sun, that represent lines of ...
with an Equatorial coordinate system, equatorial ring in 52 BCE. By 84 CE, the elliptical ring was added to the armillary sphere, while Zhang Heng's model of 125 added the celestial horizon ring and Meridian (astronomy), meridian ring.


Han calendars

The Han Chinese used astronomical studies mainly to construct and revise their calendar. In contrast to the Julian calendar (46 BCE) and Gregorian calendar (1582) of Western world, the West (but like the Hellenic calendars of Classical Greece), the Chinese calendar is a
lunisolar calendar A lunisolar calendar is a calendar in many cultures, combining lunar calendars and solar calendars. The date of Lunisolar calendars therefore indicates both the Moon phase and the time of the solar year, that is the position of the Sun in the Ea ...
, meaning that it uses the precise movements of the
Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
and Moon as time-markers throughout the year. During the spring and autumn periods of the 5th century BCE, the Chinese established the Sifen calendar (古四分历), which measured the tropical year at 36514 days (like the Julian calendar of Rome).Deng (2005), 67. Emperor Wu replaced this with the new Taichu calendar (太初历) in 104 BCE, which measured the tropical year at 3653851539 days and the lunar month at 294381 days. Since the Taichu calendar had become inaccurate over two centuries, Emperor Zhang of Han (r. 75–88 CE) halted its use and revived use of the Sifen calendar. Later, astronomer Guo Shoujing (1233–1316) would set the tropical year at 365.2425 days for his Shoushi calendar (授時曆), the same value used in the Gregorian calendar. Besides the use of the calendar for regulating agricultural practices throughout the seasons, it was also used to mark important dates in the Sexagenary cycle—constructed by celestial stems (''gan'' 干) and Earthly Branches (''zhi'' 支), each of the latter associated with an animal of the Chinese astrology, Chinese zodiac.


Astronomical theory

Zhao Shaung's 3rd-century commentary in the ''Zhoubi suanjing'' describes two astronomical theories: in one, the heavens are shaped as a hemi-spherical dome extending over the Earth, while the other compares the Earth to the central egg yolk, yolk of an egg, where the heavens are shaped as a
celestial sphere In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, ...
around the earth. The latter astronomical theory was mentioned by Yang Xiong in his ''Model Sayings'' (''Fayan'' 法言) and expounded on by Zhang Heng in his ''Spiritual Constitution of the Universe'' (''Lingxian'' 靈憲) of 120 CE. Thus, the Han-era Chinese believed in a geocentric model for the immediate Solar System and greater universe, as opposed to a Heliocentrism, heliocentric model. The Han-era Chinese discussed the illumination and shapes of heavenly bodies: were they flat and circular, or were they rounded and spherical? Jing Fang wrote in the 1st century BCE that Han astronomers believed the Sun, Moon, and planets were spherical like balls or crossbow bullets.Needham (1986a), 227. He also wrote that the Moon and planets produce no light of their own, are viewable to people on Earth only because they are illuminated by the Sun, and those parts not illuminated by the Sun would be dark on the other side. For this, Jing compared the Moon to a mirror illuminating light. In the 2nd century CE, Zhang Heng drew a similar comparison to Jing's by stating that the Sun is like fire and the Moon and planets are like water, since fire produces light and water reflects it.Needham (1986a), 414. He also repeated Jing's comment that the side of the Moon not illuminated by the Sun was left in darkness. However, Zhang noted that sunlight did not always reach the Moon since the Earth obstructs the rays during a lunar eclipse. He also noted that a solar eclipse occurred when the Moon and Sun crossed paths to block sunlight from reaching earth. In his '' Balanced Discourse'' (''Lunheng''),
Wang Chong Wang Chong (; 27 – c. 97 AD), courtesy name Zhongren (仲任), was a Chinese astronomer, meteorologist, naturalist, philosopher, and writer active during the Han Dynasty. He developed a rational, secular, naturalistic and mechanistic account ...
(27–100 CE) wrote that some Han thinkers believed that rain fell from the Heavens (i.e. where the stars were located).Needham (1986a), 468. Wang argued that, although rain fell from above, this common theory was false. He agreed with another theory that stated clouds were formed by the evaporation of water on Earth, and that since clouds disperse rain, clouds and rain are in fact one and the same; in essence, he accurately described the water cycle.


Structural engineering and public works


Materials and construction

Timber was the chief building material in Han architecture.Ebrey (1999), 76. It was used for grand palace halls, multi-story towers, multi-story residential halls, and humble abodes. However, due to wood's rapid decay over time and susceptibility to fire, the oldest wooden buildings found in China (i.e. several temple halls of Mount Wutai) date no earlier than the Tang dynasty (618–907). Architectural historian Robert L. Thorp describes the scarcity of Han-era archaeological remains, as well as the often unreliable Han-era literary and artistic sources used by historians for clues about non-existent Han architecture. What remains of Han-dynasty architecture are ruins of
brick A brick is a type of block used to build walls, pavements and other elements in masonry construction. Properly, the term ''brick'' denotes a block composed of dried clay, but is now also used informally to denote other chemically cured cons ...
and
rammed earth Rammed earth is a technique for constructing foundations, floors, and walls using compacted natural raw materials such as earth, chalk, lime, or gravel. It is an ancient method that has been revived recently as a sustainable building method. ...
walls (including aboveground city walls and underground tomb walls), rammed earth platforms for terraced altars and halls, funerary stone or brick pillar-gates, and scattered Chinese glazed roof tile, ceramic roof tiles that once adorned timber halls. Sections of the Han-era rammed earth Great Wall of China, Great Wall still exist in
Gansu Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibet ...
province, along with the Han frontier ruins of thirty beacon towers and two fortified castles with crenellations. Han walls of frontier towns and forts in
Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an autonomous region of the People's Republic of China. Its border includes most of the length of China's border with the country of Mongolia. Inner Mongolia also accounts for a ...
were typically constructed with stamped clay bricks instead of rammed earth. Thatched or tiled roofs were supported by wooden pillars, since the addition of brick, rammed earth, or mud walls of these halls did not actually support the roof. Stone and plaster were also used for domestic architecture. Tiled eaves projecting outward were built to distance falling rainwater from the walls; they were supported by ''dougong'' brackets that were sometimes elaborately decorated. Molded designs usually decorated the ends of roof tiles, as seen in artistic models of buildings and in surviving tile pieces.


Courtyard homes

Valuable clues about Han architecture can be found in Han artwork of ceramic models, paintings, and carved or stamped bricks discovered in tombs and other sites. The layout of Han tombs were also built like underground houses, comparable to the scenes of courtyard houses found on tomb bricks and in three-dimensional models. Han homes had a courtyard area (and some had multiple courtyards) with halls that were slightly elevated above it and connected by stairways. Multi-story buildings included the main colonnaded residence halls built around the courtyards as well as
watchtower A watchtower or watch tower is a type of fortification used in many parts of the world. It differs from a regular tower in that its primary use is military and from a turret in that it is usually a freestanding structure. Its main purpose is to ...
s. The halls were built with intersecting crossbeams and rafters that were usually carved with decorations; stairways and walls were usually plastered over to produce a smooth surface and then painted.


Chang'an and Luoyang, the Han capitals

The ruins of the walls of Han's first capital
Chang'an Chang'an (; ) is the traditional name of Xi'an. The site had been settled since Neolithic times, during which the Yangshao culture was established in Banpo, in the city's suburbs. Furthermore, in the northern vicinity of modern Xi'an, Qin Shi ...
still stand today at in height with a base width of .Wang (1982), 1–2. Modern archaeological surveys have proven that the eastern wall was long, the southern wall was long, the western wall was long, and the northern wall was 7,200 (23,622 ft) long. Overall the total length of walls equalled , and formed a roughly square layout (although the southern and northern walls had sections which zigzagged due to topographical concerns: rough terrain existed along the southern wall and the course of the Wei River obstructed the straight path of the northern wall). The city's moat was wide and deep; the remains of what were wooden bridges have been discovered along the moat.Wang (1982), 2. Chang'an had twelve gatehouses leading into the city, three for each side of the wall, and acted as terminus points for the main avenues.Wang (1982), 2–3. Every gatehouse had three gateway entrances that were each wide; Han-era writers claimed that each gateway could accommodate the traffic of four horse-drawn carriages at once. Sewage collection and disposal, The drainage system included many drainholes that were dug under these gates and lined with bricks that form arches, where ceramic water pipes have been found that once connected to the ditches built alongside the major streets.Wang (1982), 4. Only some wall sections and platform foundations of the city's once lavish imperial palaces remain.Wang (1982), 4–6. Likewise, the stone foundations of the armory were also discovered, but its wooden architecture had long since disappeared. Some sections of the wall ruins of Han's second capital
Luoyang Luoyang is a city located in the confluence area of Luo River (Henan), Luo River and Yellow River in the west of Henan province. Governed as a prefecture-level city, it borders the provincial capital of Zhengzhou to the east, Pingdingshan to the ...
still stand at in height and in width at the base. The eastern wall was long, the western wall was long, and the northern wall was long, yet the southern wall was washed away when the Luo River (Henan), Luo River changed its course centuries ago; by using the terminus points of the eastern and western walls, historians estimate that the southern wall was long. The overall walled enclosure formed a rectangular shape, yet with some disruptive curves due to topographical obstructions.Wang (1982), 30. Like Chang'an, Luoyang had twelve gatehouses, three for each side of the wall, while each gatehouse had three gateway entrances which led to major avenues within the city.Wang (1982), 30–31. The rammed earth foundational platforms of religious altars and terraces still stand today outside of the walled perimeter of Luoyang, Society and culture of the Han dynasty, dedicated to the worship of deities and where state sacrifices were conducted.Wang (1982), 39. They were approached by long ramps and once had timber halls built on top with verandas on the lower levels.


Underground tombs

By the 1980s, over ten thousand brick-and-stone underground Han tombs had been discovered throughout China.Wang (1982), 175. Earlier Chinese tombs dating to the Warring States were often vertically dug pits lined with wooden walls.Wang (1982), 176. In digging the tomb sites, Han workers would first build vertical pits and then dig laterally, hence the name "horizontal pits" for Han tombs; this method was also used for tomb sites dug into the sides of mountains. The walls of most Western Han tombs were built of large hollow bricks while the smaller, non-hollow brick type that dominated Eastern Han tomb architecture (with some made out of stone) appeared in the late Western Han.Wang (1982), 175, 177–178. The smaller brick type was better-suited for Han tomb archways at entrances, vault (architecture), vaulted chambers, and domed roofs. Underground vaults and domes did not require buttress supports since they were held in place by earthen pits.Watson (2000), 108. The use of brick vaults and domes in aboveground Han structures is unknown. The layout of tombs dug into the sides of mountains typically had a front chamber, side chambers, and a rear chambers designed to imitate a complex of aboveground halls. The tomb of King Liu Sheng, Prince of Zhongshan, Liu Sheng (d. 113 BCE) in Hebei province not only had a front hall with window drapes and grave goods, carriages and horses in the southern separate side chamber, and storage goods in the northern side chamber, but also the remains of real timber houses with tiled roofs erected within (along with a house made of stone slabs and two stone doors in the rear chamber). Doors made completely out of stone were found in many Han tombs Qianling Mausoleum, as well as tombs in later dynasties. A total of twenty-nine monumental brick or stone-carved pillar-gates (''que (tower), que'') from the Han dynasty have survived and can be found in the aboveground areas around Han tomb and shrine sites. They often formed part of outer walls, usually flanking an entry but sometimes at the corners of walled enclosures. Although they lack wooden and ceramic components, they feature imitation roof tiles, eaves, porches, and Baluster, balustrades.


Boreholes and mining shafts

On Han tomb brick reliefs of Sichuan province, scenes of
borehole A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water ( drilled water well and tube well), other liquids (such as petro ...
drilling for mining projects are shown. They show towering
derrick A derrick is a lifting device composed at minimum of one guyed mast, as in a gin pole, which may be articulated over a load by adjusting its guys. Most derricks have at least two components, either a guyed mast or self-supporting tower, and a ...
s lifting liquid
brine Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for br ...
through Pipeline transport, bamboo pipes to the surface so that the brine could be Distillation, distilled in evaporation pans over the heat of furnaces and produce
salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
.Loewe (1968), 191–194. The furnaces were heated by
natural gas Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...
brought by bamboo pipes, with gas brought up from below the surface. The drill bit for digging boreholes was operated by a team of men jumping on and off a beam while the boring tool was rotated by a draft animal, usually oxen or water buffaloes. Han boreholes dug for collecting brine could reach hundreds of meters (feet) beneath the Earth's surface. Shaft mining, Mining shafts dating to the Han dynasty have been found which reach depths of hundreds of meters (feet) beneath the earth, complete with spacious underground rooms structured by timber frames along with ladders and iron tools left behind.


Ceramic model buildings

There are Han-era literary references to tall towers found in the capital cities; they often served as watchtowers, astronomical Observatory, observatories, and religious establishments meant to attract the favor of Xian (Taoism), immortals. The court eunuchs Zhao Zhong and
Zhang Rang The Ten Attendants, also known as the Ten Eunuchs, were a group of influential eunuch-officials in the imperial court of Emperor Ling ( 168–189) in Eastern Han China. Although they are often referred to as a group of 10, there were actually 12 ...
discouraged the aloof Emperor Ling of Han (r. 168–189 CE) from ascending to the top floors of tall towers (claiming it would cause bad luck), in order to conceal from him the enormous palatial mansions the eunuchs built for themselves in Luoyang. It is not known for certain whether or not miniature ceramic models of residential towers and watchtowers found in Han-dynasty tombs are completely faithful representations of such timber towers, yet they reveal vital clues about lost timber architecture. There are only a handful of existing ceramic models of multi-story towers from pre-Han and Western Han eras; the bulk of the hundreds of towers found so far were made during the Eastern Han period.Steinhardt (2005), "Pleasure Tower Model," 275–278. Model towers could be fired as one piece in the kiln or assembled from several different ceramic pieces to create the whole.Steinhardt (2005), "Pleasure Tower Model," 275–277. No one tower is a duplicate of the other, yet they share common features. They often had a walled courtyard at the bottom, a balcony with balustrades and windows for every floor, roof tiles capping and concealing the ceiling rafters, human figures peering out the windows or standing on the balconies, door knockers, and Dogs in ancient China, pets such as dogs in the bottom courtyard. Perhaps the most direct pieces of evidence to suggest that miniature ceramic tower models are faithful representations of real-life Han timber towers are tile patterns.Steinhardt (2005), "Tower Model" 283–284. Artistic patterns found on the circular tiles that cap the eave-ends on the miniature models are exact matches of patterns found on real-life Han roof tiles excavated at sites such as the royal palaces in Chang'an and Luoyang, and even the tiles of the original White Horse Temple. Besides towers, other ceramic models from the Han reveal a variety of building types. This includes multi-story Warehouse, storehouses such as Granary, granaries, courtyard houses with multi-story halls, kiosks, walled gate towers, mills, manufactories and workshops, animal pens, outhouses, and water wells.Steinhardt (2005), "Pleasure Tower Model," 278. Even models of single-story farmhouses show a great amount of detail, including tiled roofs, courtyards, steps leading to walkways, farmyards with troughs and basins, parapets, and privies. Models of granaries and storehouses had tiled rooftops, ''dougong'' brackets, windows, and stilt supports raising them above ground level. Han models of water wells sometimes feature tiny tiled roofs supported by beams that house the rope pulley used for lifting the bucket.


Roads, bridges, and canals

In order to facilitate commerce and communication as well as speed the process of tax collection and movement of military troops, the Han government sponsored the building of new roads, bridges, and :Canals in China, canal waterways. These include repairs and renovation work on the Dujiangyan Irrigation System of Sichuan and Zhengguo Canal of Shaanxi, both of which were built by the previous State of Qin.Wang (1982), 59. Accepting the proposal of Ni Kuang, Ni Kuan, in 111 BCE Emperor Wu commissioned Er to lead the project of creating extensions to the Zhengguo Canal that could irrigate nearby terrain elevated above the main canal.Needham (1986d), 286. Since a large amount of silt had built up over time at the bottom of the Zhengguo Canal (causing flooding), in 95 BCE another project was initiated to tap irrigation waters from further up the Jing River, requiring the dredging of a new long canal following a Contour canal, contour line above the Zhengguo. The Han state also maintained a system of dikes to protect farmland from seasonal floods. Roadways, wooden bridges, postal stations, and relay stations were occasionally repaired, while many new facilities such as these were established. As written by Han authors, roads built during the Han were tamped down with metal rammers, yet there is uncertainty over the materials used;
Joseph Needham Noel Joseph Terence Montgomery Needham (; 9 December 1900 – 24 March 1995) was a British biochemist, historian of science and sinologist known for his scientific research and writing on the history of Chinese science and technology, in ...
speculates that they were rubble and gravel. The widths of roads ranged from narrow footpaths where only a single horse or oxen could pass at once to large highways that could accommodate the simultaneous passage of nine horse-drawn chariots abreast. Fortified Han roadways were built as far west as Shanshan (Loulan Kingdom, Loulan) near the Lop Desert, while Protectorate of the Western Regions, Han forces utilized routes that traversed north of the Taklamakan Desert towards Kashgar.Needham (1986d), 18. A vast network of roads, fortified passes, and wooden bridges built over rushing torrents in steep gorges of the Qin Mountains was consolidated during the Han, known as the gallery roads. During the reign of Emperor Wu, roads were built to connect newly conquered territories in what is now
Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...
in the far southwest as well as the Korean Peninsula in the far northeast. One of the most common bridge-types built during the Han was the wooden-trestle
beam bridge Beam bridges are the simplest structural forms for bridge spans supported by an abutment or pier at each end. No moments are transferred throughout the support, hence their structural type is known as '' simply supported''. The simplest beam ...
, described by literary sources and seen in reliefs carved on tomb bricks.Needham (1986d), 149–150. Evidence for
arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct ...
s is elusive: one outside of Chengdu's south gate is claimed to date to the Han period, while that built by Ma Xian (馬賢) (fl. 135 CE) was certainly a beam bridge.Needham (1986d), 171–172. In artwork, a relief sculpture from a Han tomb in Sichuan province shows an arch bridge with a gradual curve, suggesting that it is segmental, although the use of such bridges are not entirely confirmed.Liu (2002), 56. Although there are rare references to
simple suspension bridge A simple suspension bridge (also rope bridge, swing bridge (in New Zealand), suspended bridge, hanging bridge and catenary bridge) is a primitive type of bridge in which the deck of the bridge lies on two parallel load-bearing cables that ar ...
s in Han sources, these are only mentioned in connection with travels to foreign countries in the Himalaya, Hindukush and Afghanistan, demonstrating the antiquity of the invention there.Needham (1986d), 187–188. Floating
pontoon bridge A pontoon bridge (or ponton bridge), also known as a floating bridge, uses float (nautical), floats or shallow-draft (hull), draft boats to support a continuous deck for pedestrian and vehicle travel. The buoyancy of the supports limits the maxi ...
s made of boats secured by iron chains were built during the Han (some even spanning the Yellow River and
Yangzi River The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows ...
) and were most often employed for military purposes since they could be easily assembled and then disassembled.


Medicine

Much of the beliefs held by Han-era physicians are known to modern historians through such texts as the ''Huangdi Neijing, Yellow Emperor's Inner Canon'' (''Huangdi neijing'') medical corpus, which was compiled from the 3rd to 2nd century BCE and was mentioned in the ''Book of Later Han''.Csikszentmihalyi (2006), 181–182. It is clear from this text and others that their metaphysical beliefs in the Wuxing (Chinese philosophy), five phases and yin and yang dictated their medical decisions and assumptions. The Han-era Chinese believed that each Zang-fu, organ in the body was associated with one of the five phases (metal 金, wood 木, water 水, fire 火, earth 土) and had two circulatory qi channels (任督二脉). If these channels were disrupted, Han medical texts suggest that one should consume an edible material associated with one of these phases that would counteract the organ's prescribed phase and thus restore one's health. For example, the Chinese believed that when the heart—associated with the fire phase—caused one to become sluggish, then one should eat sour food because it was associated with the wood phase (which promoted fire). The Han Chinese also believed that by using pulse diagnosis, a physician could determine which organ of the body emitted "Qi, vital energy" (''qi'') and what qualities the latter had, in order to figure out the exact disorder the patient was suffering.Hsu (2001), 75. Despite the influence of metaphysical theory on medicine, Han texts also give practical advice, such as the proper way to perform clinical lancing to remove an abscess. The ''Huangdi neijing'' noted the symptoms and reactions of people with various diseases of the liver, heart, spleen, lung, or kidneys in a 24-hour period, which was a recognition of circadian rhythm, although explained in terms of the five phases. In his ''Jinkui Yaolue, Essential Medical Treasures of the Golden Chamber'' (''Jinkui yaolue''), Zhang Zhongjing (c. 150 – c. 219 CE) was the first to suggest a regulated diet rich in certain vitamins could prevent Nutrition disorder, different types of disease, an idea which led Hu Sihui (fl. 1314–1330) to prescribe a diet rich in Thiamin, Vitamin B1 as a treatment for beriberi. Zhang's major work was the Shang Han Lun, ''Treatise on Cold Injury and Miscellaneous Disorders'' (''Shanghan zabing lun''). His contemporary and alleged associate Hua Tuo (d. 208 CE) was a physician who had studied the ''Huangdi neijing'' and became knowledgeable in Chinese herbology.de Crespigny (2007), 332. Hua Tuo used anesthesia on patients during surgery and created an ointment that was meant to fully heal surgery wounds within a month. In one diagnosis of an ill woman, he deciphered that she bore a dead fetus within her womb which he then removed, curing her of her ailments. Historical sources say that Hua Tuo rarely practiced moxibustion and acupuncture. The first mentioning of acupuncture in Chinese literature appeared in the ''Huangdi neijing''. Acupuncture needles made of gold were found in the tomb of the Han King Liu Sheng, Prince of Zhongshan, Liu Sheng (d. 113 BCE). Some stone-carved depictions of acupuncture date to the Eastern Han Era (25–220 CE).Omura (2003), 19–22. Hua Tuo also wrote about the allegedly life-prolonging exercises of
calisthenics Calisthenics (American English) or callisthenics (British English) ( /ˌkælɪsˈθɛnɪks/) is a form of strength training consisting of a variety of movements that exercise large muscle groups (gross motor movements), such as standing, graspi ...
. In the 2nd-century-BCE medical texts excavated from the
Mawangdui Mawangdui () is an archaeological site located in Changsha, China. The site consists of two saddle-shaped hills and contained the tombs of three people from the Changsha Kingdom during the western Han dynasty (206 BC – 9 AD): the Chancellor Li ...
, illustrated diagrams of calisthenic positions are accompanied by descriptive titles and captions.Loewe (1994), 65. Vivienne Lo writes that the modern physical exercises of T'ai chi ch'uan, taijiquan and qigong are derived from Han-era calisthenics.Lo (2001), 23.


Cartography

Cartography, Map-making in China preceded the Han dynasty. Since two 4th-century-BCE silk maps from the Qin (state), State of Qin (found in
Gansu Gansu (, ; alternately romanized as Kansu) is a province in Northwest China. Its capital and largest city is Lanzhou, in the southeast part of the province. The seventh-largest administrative district by area at , Gansu lies between the Tibet ...
, displaying the region about the Jialing River) show Li (unit), the measured distance between timber-gathering sites, Mei-ling Hsu argues that these are to be considered the first known Economic geography, economic maps (as they predate the maps of Ancient Rome, the Roman geographer Strabo, c. 64 BCE – 24 CE).Hsu (1993), 90–93. Maps from the Han period have also been uncovered by modern archaeologists, such as those found Mawangdui Silk Texts, with 2nd-century-BCE silk texts at
Mawangdui Mawangdui () is an archaeological site located in Changsha, China. The site consists of two saddle-shaped hills and contained the tombs of three people from the Changsha Kingdom during the western Han dynasty (206 BC – 9 AD): the Chancellor Li ...
. In contrast to the Qin maps, the Han maps found at Mawangdui employ a more diverse use of map symbols, cover a larger terrain, and display information on local populations and even pinpoint locations of military camps. One of the maps discovered at
Mawangdui Mawangdui () is an archaeological site located in Changsha, China. The site consists of two saddle-shaped hills and contained the tombs of three people from the Changsha Kingdom during the western Han dynasty (206 BC – 9 AD): the Chancellor Li ...
shows positions of Military history of China (pre-1911), Han military garrisons which were to attack Nanyue in 181 BCE.Hansen (2000), 125. In Chinese literature, the oldest reference to a map comes from the year 227 BCE, when the assassin Jing Ke was to present a map to Ying Zheng 嬴政, King of Qin (ruling later as
Qin Shi Huang Qin Shi Huang (, ; 259–210 BC) was the founder of the Qin dynasty and the first emperor of a unified China. Rather than maintain the title of "king" ( ''wáng'') borne by the previous Shang and Zhou rulers, he ruled as the First Emperor ( ...
, r. 221–210 BCE) on behalf of Crown Prince Dan of Yan. Instead of presenting the map, he pulled out a dagger from his scroll, yet was unable to kill Ying Zheng.Needham (1986a), 534–535. The ''Rites of Zhou'' (''Zhouli''), compiled during the Han and commented by Liu Xin in the 1st century CE, mentioned the use of maps for governmental provinces and districts, principalities, frontier boundaries, and locations of ores and minerals for mining facilities. The first Chinese gazetteer was written in 52 CE and included information on territorial divisions, the founding of cities, and local products and customs. Pei Xiu (224–271 CE) was the first to describe in detail the use of a Scale (map), graduated scale and Grid reference, geometrically plotted reference grid. However, historians Howard Nelson, Robert Temple, and Rafe de Crespigny argue that there is enough literary evidence that Zhang Heng's now lost work of 116 CE established the geometric reference grid in Chinese cartography (including a line from the ''Book of Later Han'': "[Zhang Heng] cast a network of coordinates about heaven and earth, and reckoned on the basis of it"). Although there is speculation fueled by the report in Sima's ''Records of the Grand Historian'' that a gigantic
raised-relief map A raised-relief map, terrain model or embossed map is a three-dimensional representation, usually of terrain, materialized as a physical artifact. When representing terrain, the vertical dimension is usually exaggerated by a factor between fiv ...
representing the Qin Empire is located within the tomb of Qin Shi Huang, it is known that small raised-relief maps were created during the Han dynasty, such as one made out of rice by the military officer Ma Yuan (Han dynasty), Ma Yuan (14 BCE – 49 CE).Temple (1986), 179.


Nautics and vehicles

In 1975, an ancient shipyard discovered in Guangzhou is now dated to the late 3rd century BCE, made during either the
Qin dynasty The Qin dynasty ( ; zh, c=秦朝, p=Qín cháo, w=), or Ch'in dynasty in Wade–Giles romanization ( zh, c=, p=, w=Ch'in ch'ao), was the first Dynasties in Chinese history, dynasty of Imperial China. Named for its heartland in Qin (state), ...
(221–206 BCE) or early Western Han dynasty. It had three large platforms capable of building wooden ships that were long, wide, and had a weight capacity of 60 metric tons. Another Han shipyard in what is now Anhui province had a government-operated maritime workshop where battle ships were assembled.Nishijima (1986), 582. The widespread use of iron tools during the Han dynasty was essential for crafting such vessels. The southward expansion of the Han dynasty led to new trade routes and diplomatic contact with foreign kingdoms. In 111 BCE, Emperor Wu Han–Nanyue War, conquered the Kingdom of Nanyue in what is now modern Northern and southern Vietnam, northern Vietnam and
Guangdong Guangdong (, ), alternatively romanized as Canton or Kwangtung, is a coastal province in South China on the north shore of the South China Sea. The capital of the province is Guangzhou. With a population of 126.01 million (as of 2020) ...
,
Guangxi Guangxi (; ; Chinese postal romanization, alternately romanized as Kwanghsi; ; za, Gvangjsih, italics=yes), officially the Guangxi Zhuang Autonomous Region (GZAR), is an Autonomous regions of China, autonomous region of the People's Republic ...
,
Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is ...
; thereafter he opened up maritime trade to both Southeast Asia and the Indian Ocean, as foreign merchants brought lapis lazuli, pearls, jade, and glasswares to the Han Empire from this southern sea route.Nishijima (1986), 579–580. When a group of travelers from the Roman Empire (allegedly diplomats of Marcus Aurelius but most likely Roman commerce, Roman merchants) History of the Han dynasty, came to the Han court in 166 CE, they allegedly came from this southern trade route. By at least the 1st century CE—as proven by Eastern Han ceramic miniature models of ships found in various tombs—the Chinese would have been able to brave distant waters with the new steering invention of the stern-mounted
rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...
. This came to replace the less efficient steering oar. While ancient China was home to various ship designs, including the layered and fortified lou chuan, tower ship meant for calm waters of lakes and river, the Junk (ship), ''junk'' design (''jun'' 船) created by the 1st century was China's first seaworthy sailing ship. The typical junk has a square-ended Bow (ship), bow and stern, a flat-bottomed Hull (watercraft), hull or Carvel (boat building), carvel-shaped hull with no keel or sternpost, and Bulkhead (partition), solid transverse bulkheads in the place of Boat building, structural ribs found in Western seacrafts. Since the Chinese junk lacked a sternpost, the rudder was attached to the back of the ship by use of either socket-and-jaw or block and tackle (which differed from the later European pintle and gudgeon design of the 12th century). As written by a 3rd-century author, junks had Junk Rig, for-and-aft rigs and lug sails. Although horse and ox-drawn carts and spoke-wheeled chariots had existed in China long before the Han dynasty, it was not until the 1st century BCE that literary evidence pointed to the invention of the
wheelbarrow A wheelbarrow is a small hand-propelled vehicle, usually with just one wheel, designed to be pushed and guided by a single person using two handles at the rear, or by a sail to push the ancient wheelbarrow by wind. The term "wheelbarrow" is mad ...
, while painted murals on Han tomb walls of the 2nd century CE show the wheelbarrow in use for hauling goods. While the 'throat-and-girth' harness was still in use throughout much of the ancient world (placing an excessive amount of pressure on horses' necks), the Chinese were placing a wooden yoke across their horses' chests with traces to the chariot shaft by the 4th century BCE in the State of Chu (as seen on a Chu lacquerware). By Han times, the Chinese replaced this heavy yoke with a softer breast strap, as seen in Han stamped bricks and carved tomb reliefs. In the final stage of evolution, the modern horse collar was invented in China by the 5th century, during the Northern Wei period.


Weaponry and war machines

The pivot catapult, known as the traction trebuchet, had existed in China since the
Warring States period The Warring States period () was an era in History of China#Ancient China, ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period and concluded ...
(as evidenced by the ''Mozi'').Turnbull (2001), 18. It was regularly used in sieges during the Han dynasty, by both besiegers and the besieged. The most common projectile weapon used during the Han dynasty was the small handheld, trigger-activated History of crossbows, crossbow (and to a lesser extent, the repeating crossbow), first invented in China during the 6th or 5th century BCE. Although the nomadic
Xiongnu The Xiongnu (, ) were a tribal confederation of nomadic peoples who, according to ancient Chinese sources, inhabited the eastern Eurasian Steppe from the 3rd century BC to the late 1st century AD. Modu Chanyu, the supreme leader after 20 ...
were able to twist their waists slightly while horse-riding and shoot arrows at targets behind them, the official Chao Cuo (d. 154 BCE) deemed the Chinese crossbow superior to the Xiongnu bow.Di Cosmo (2002), 203. The Han Chinese also employed chemical warfare. In quelling a peasant revolt near Guiyang in 178 CE, the imperial Han forces had horse-drawn chariots carrying
bellows A bellows or pair of bellows is a device constructed to furnish a strong blast of air. The simplest type consists of a flexible bag comprising a pair of rigid boards with handles joined by flexible leather sides enclosing an approximately airtigh ...
that were used to pump powdered lime (calcium oxide) at the rebels, who were dispersed.Needham (1986f), 167. In this same instance, they also lit incendiary device, incendiary rags tied to the tails of horses, so that the frightened horses would rush through the enemy lines and disrupt their formations. To deter pursuits of marching infantry or riding cavalry, the Han Chinese made caltrops (barbed iron balls with sharp spikes sticking out in all directions) that could be scattered on the ground and pierce the feet or hooves of those who were unaware of them.


See also

*Chinese characters#Han dynasty *List of Chinese discoveries *List of Chinese inventions *List of inventions and discoveries of Neolithic China *History of science and technology in China *History of science and technology, Science and technology


Notes


References

*Adshead, Samuel Adrian Miles. (2000). ''China in World History''. London: MacMillan Press Ltd. New York: St. Martin's Press. . *Arndt, Jörg, and Christoph Haenel. (2001). ''Pi Unleashed''. Translated by Catriona and David Lischka. Berlin: Springer. . *Balchin, Jon. (2003). ''Science: 100 Scientists Who Changed the World''. New York: Enchanted Lion Books. . *Barbieri-Low, Anthony J. (2007). ''Artisans in Early Imperial China''. Seattle & London: University of Washington Press. . *Berggren, Lennart, Jonathan M. Borwein, and Peter B. Borwein. (2004). ''Pi: A Source Book''. New York: Springer. . *Hans Bielenstein, Bielenstein, Hans. (1986). "Wang Mang, the Restoration of the Han Dynasty, and Later Han," in ''The Cambridge History of China: Volume I: the Ch'in and Han Empires'', 221 B.C. – A.D. 220, 223–290. Edited by Denis Twitchett and Michael Loewe. Cambridge: Cambridge University Press. . *Block, Leo. (2003). ''To Harness the Wind: A Short History of the Development of Sails''. Annapolis: Naval Institute Press. . *Bowman, John S. (2000). ''Columbia Chronologies of Asian History and Culture''. New York: Columbia University Press. *Buisseret, David. (1998). ''Envisioning the City: Six Studies in Urban Cartography''. Chicago: University Of Chicago Press. . *Chang, Chun-shu. (2007). ''The Rise of the Chinese Empire: Volume II; Frontier, Immigration, & Empire in Han China, 130 B.C. – A.D. 157''. Ann Arbor: University of Michigan Press. . *. *Chung, Chee Kit. (2005). "Longyamen is Singapore: The Final Proof?," in ''Admiral Zheng He & Southeast Asia''. Singapore: Institute of Southeast Asian Studies. . *Cotterell, Maurice. (2004). ''The Terracotta Warriors: The Secret Codes of the Emperor's Army''. Rochester: Bear and Company. . *Csikszentmihalyi, Mark. (2006). ''Readings in Han Chinese Thought''. Indianapolis and Cambridge: Hackett Publishing Company, Inc. . *Cullen, Christoper. (2006). ''Astronomy and Mathematics in Ancient China: The Zhou Bi Suan Jing''. Cambridge: Cambridge University Press. . *Day, Lance and Ian McNeil. (1996). ''Biographical Dictionary of the History of Technology''. New York: Routledge. . *Joseph Dauben, Dauben, Joseph W. (2007). "Chinese Mathematics" in ''The Mathematics of Egypt, Mesopotamia, China, India, and Islam: A Sourcebook'', 187–384. Edited by Victor J. Katz. Princeton: Princeton University Press. . *Rafe de Crespigny, de Crespigny, Rafe. (2007). ''A Biographical Dictionary of Later Han to the Three Kingdoms (23–220 AD)''. Leiden: Koninklijke Brill. . *Deng, Yingke. (2005). ''Ancient Chinese Inventions''. Translated by Wang Pingxing. Beijing: China Intercontinental Press (五洲传播出版社). . *Dewar, Richard. (2002). ''Stoneware''. Philadelphia: University of Pennsylvania Press. . *Nicola Di Cosmo, Di Cosmo, Nicola. (2002). ''Ancient China and its Enemies: The Rise of Nomadic Power in East Asian History''. Cambridge: Cambridge University Press. . *Ebrey, Patricia. (1986). "The Economic and Social History of Later Han," in ''Cambridge History of China: Volume I: the Ch'in and Han Empires, 221 B.C. – A.D. 220'', 608–648. Edited by Denis Twitchett and Michael Loewe. Cambridge: Cambridge University Press. . *Ebrey, Patricia. (1999). ''The Cambridge Illustrated History of China''. Cambridge: Cambridge University Press. . *John K. Fairbank, Fairbank, John K. and Merle Goldman. (1998). ''China: A New History, Enlarged Edition''. Cambridge: Harvard University Press. . *Fong, Mary H. "Antecedents of Sui-Tang Burial Practices in Shaanxi," ''Artibus Asiae'' (Volume 51, Number 3/4, 1991): 147–198. *Greenberger, Robert. (2006). ''The Technology of Ancient China''. New York: Rosen Publishing Group, Inc. . *Hansen, Valerie. (2000). ''The Open Empire: A History of China to 1600''. New York & London: W.W. Norton & Company. . *Hargett, James M. "Song Dynasty Local Gazetteers and Their Place in The History of Difangzhi Writing," ''Harvard Journal of Asiatic Studies'' (Volume 56, Number 2, 1996): 405–442. *Hinsch, Bret. (2002). ''Women in Imperial China''. Lanham: Rowman & Littlefield Publishers, Inc. . *Hiromi, Kinoshita. (2005). "Storehouse model," in ''Recarving China's Past: Art, Archaeology, and Architecture of the 'Wu Family Shrines, 290–291. Edited by Naomi Noble Richard. New Haven and London: Yale University Press and Princeton University Art Museum. . *. *Hsu, Elisabeth. (2001). "Pulse diagnostics in the Western Han: how mai and qi determine bing," in ''Innovations in Chinese Medicine'', 51–92. Edited by Elisabeth Hsu. Cambridge, New York, Oakleigh, Madrid, and Cape Town: Cambridge University Press. . *Hsu, Mei-ling. "The Qin Maps: A Clue to Later Chinese Cartographic Development," ''Imago Mundi'' (Volume 45, 1993): 90–100. *Ray Huang, Huang, Ray. (1988). ''China: A Macro History''. Armonk & London: M.E. Sharpe Inc., an East Gate Book. . *Jin, Guantao, Fan Hongye, and Liu Qingfeng. (1996). "Historical Changes in the Structure of Science and Technology (Part Two, a Commentary)" in ''Chinese Studies in the History and Philosophy of Science and Technology'', 165–184, edited by Fan Dainian and Robert S. Cohen, translated by Kathleen Dugan and Jiang Mingshan. Dordrecht: Kluwer Academic Publishers. . *Juliano, Annette L. (2005). "Model of a farm compound with human figure, sow and suckling pig, chickens, trough, and basin," in ''Recarving China's Past: Art, Archaeology, and Architecture of the 'Wu Family Shrines, 286–289. Edited by Naomi Noble Richard. New Haven and London: Yale University Press and Princeton University Art Museum. . *Krebs, Robert E. (2003). ''The Basics of Earth Science''. Westport: Greenwood Press of Greenwood Publishing Group, Inc. . *Lander, Brian. “State Management of River Dikes in Early China: New Sources on the Environmental History of the Central Yangzi Region.” T’oung Pao 100.4–5 (2014): 325–62. *Lin, Yun. "History of the Crossbow," in ''Chinese Classics & Culture'', 1993, No. 4: 33–37. *Liu, Cary Y. (2005). "Green-glazed wellhead," in ''Recarving China's Past: Art, Archaeology, and Architecture of the 'Wu Family Shrines, 292–295. Edited by Naomi Noble Richard. New Haven and London: Yale University Press and Princeton University Art Museum. . *Liu, Guilin, Feng Lisheng, Jiang Airong, and Zheng Xiaohui. (2003). "The Development of E-Mathematics Resources at Tsinghua University Library (THUL)" in ''Electronic Information and Communication in Mathematics'', 1–13. Edited by Bai Fengshan and Bern Wegner. Berlin, Heidelberg, and New York: Springer Verlag. . *Liu, Xujie (2002). "The Qin and Han Dynasties" in ''Chinese Architecture'', 33–60. Edited by Nancy S. Steinhardt. New Haven: Yale University Press. . *Lloyd, Geoffrey Ernest Richard. (1996). ''Adversaries and Authorities: Investigations into Ancient Greek and Chinese Science''. Cambridge: Cambridge University Press. . *Lo, Vivienne. (2001). "The influence of nurturing life culture on the development of Western Han acumoxa therapy," in ''Innovation in Chinese Medicine'', 19–50. Edited by Elisabeth Hsu. Cambridge, New York, Oakleigh, Madrid, and Cape Town: Cambridge University Press. . *Michael Loewe, Loewe, Michael. (1968). ''Everyday Life in Early Imperial China during the Han Period 202 BC–AD 220''. London: B.T. Batsford Ltd.; New York: G.P. Putnam's Sons. . *Loewe, Michael. (1994). ''Divination, Mythology and Monarchy in Han China''. Cambridge, New York, and Melbourne: Cambridge University Press. . *Mao, Ying. "Introduction of Crossbow Mechanism," in ''Southeast Culture'', 1998, No. 3: 109–117. . *McClain, Ernest G. and Ming Shui Hung. "Chinese Cyclic Tunings in Late Antiquity," ''Ethnomusicology'', Vol. 23, No. 2 (May, 1979): 205–224. *Minford, John and Joseph S.M. Lau. (2002). ''Classical Chinese literature: an anthology of translations''. New York: Columbia University Press. . *Morton, W. Scott and Charlton M. Lewis. (2005). ''China: Its History and Culture''. New York: McGraw-Hill, Inc. . *Mott, Lawrence V. (1991). ''The Development of the Rudder: A Technological Tale''. College Station: Texas A & M University Press. . *Needham, Joseph. (1972). ''Science and Civilisation in China: Volume 1, Introductory Orientations''. London: Syndics of the Cambridge University Press. . *Needham, Joseph. (1986a). ''Science and Civilisation in China: Volume 3; Mathematics and the Sciences of the Heavens and the Earth''. Taipei: Caves Books, Ltd. . *Needham, Joseph. (1986b). ''Science and Civilisation in China: Volume 4, Physics and Physical Technology; Part 1, Physics''. Taipei: Caves Books Ltd. . *Needham, Joseph. (1986c). ''Science and Civilization in China: Volume 4, Physics and Physical Technology; Part 2, Mechanical Engineering''. Taipei: Caves Books Ltd. . *Needham, Joseph. (1986d). ''Science and Civilisation in China: Volume 4, Physics and Physical Technology, Part 3, Civil Engineering and Nautics''. Taipei: Caves Books Ltd. . *Needham, Joseph and Tsien Tsuen-Hsuin. (1986e). ''Science and Civilisation in China: Volume 5, Chemistry and Chemical Technology, Part 1, Paper and Printing''. Taipei: Caves Books, Ltd. . *Needham, Joseph. (1986f). ''Science and Civilisation in China: Volume 5, Chemistry and Chemical Technology, Part 7, Military Technology; the Gunpowder Epic''. Taipei: Caves Books, Ltd. . *Nishijima, Sadao. (1986). "The Economic and Social History of Former Han," in ''Cambridge History of China: Volume I: the Ch'in and Han Empires, 221 B.C. – A.D. 220'', 545–607. Edited by Denis Twitchett and Michael Loewe. Cambridge: Cambridge University Press. . *Omura, Yoshiaki. (2003). ''Acupuncture Medicine: Its Historical and Clinical Background''. Mineola: Dover Publications, Inc. . *Pigott, Vincent C. (1999). ''The Archaeometallurgy of the Asian Old World''. Philadelphia: University of Pennsylvania Museum of Archaeology and Anthropology. . *Ronan, Colin A. (1994). ''The Shorter Science and Civilisation in China: 4'' (an abridgement of Joseph Needham's work). Cambridge: Cambridge University Press. . *Shen, Kangshen, John N. Crossley and Anthony W.C. Lun. (1999). ''The Nine Chapters on the Mathematical Art: Companion and Commentary''. Oxford: Oxford University Press. . *Steinhardt, Nancy Shatzman. "The Tang Architectural Icon and the Politics of Chinese Architectural History," ''The Art Bulletin'' (Volume 86, Number 2, 2004): 228–254. *Steinhardt, Nancy N. (2005). "Pleasure tower model," in ''Recarving China's Past: Art, Archaeology, and Architecture of the 'Wu Family Shrines, 275–281. Edited by Naomi Noble Richard. New Haven and London: Yale University Press and Princeton University Art Museum. . *Steinhardt, Nancy N. (2005). "Tower model," in ''Recarving China's Past: Art, Archaeology, and Architecture of the 'Wu Family Shrines, 283–285. Edited by Naomi Noble Richard. New Haven and London: Yale University Press and Princeton University Art Museum. . *Straffin, Philip D., Jr. "Liu Hui and the First Golden Age of Chinese Mathematics," ''Mathematics Magazine'', Vol. 71, No. 3 (Jun., 1998): 163–181. *Sun, Xiaochun and Jacob Kistemaker. (1997). ''The Chinese Sky During the Han: Constellating Stars and Society''. Leiden, New York, Köln: Koninklijke Brill. . *. *Temple, Robert. (1986). ''The Genius of China: 3,000 Years of Science, Discovery, and Invention''. With a foreword by Joseph Needham. New York: Simon and Schuster, Inc. . *Thorp, Robert L. "Architectural Principles in Early Imperial China: Structural Problems and Their Solution," ''The Art Bulletin'', Vol. 68, No. 3 (Sep., 1986): pp. 360–378. *Tom, K.S. (1989). ''Echoes from Old China: Life, Legends, and Lore of the Middle Kingdom''. Honolulu: The Hawaii Chinese History Center of the University of Hawaii Press. . *Turnbull, Stephen R. (2001). ''Siege Weapons of the Far East''. Oxford: Osprey Publishing Ltd. . *Turnbull, Stephen R. (2002). ''Fighting Ships of the Far East: China and Southeast Asia 202 BC–AD 1419''. Oxford: Osprey Publishing, Ltd. . *Wagner, Donald B. (1993). ''Iron and Steel in Ancient China: Second Impression, With Corrections''. Leiden: E.J. Brill. . *Wagner, Donald B. (2001). ''The State and the Iron Industry in Han China''. Copenhagen: Nordic Institute of Asian Studies Publishing. . *Wang Zhongshu, Wang, Zhongshu. (1982). ''Han Civilization''. Translated by K.C. Chang and Collaborators. New Haven and London: Yale University Press. . * Watson, William. (2000). ''The Arts of China to AD 900''. New Haven: Yale University Press. . *Woodman, Richard. (2002). The History of the Ship: The Comprehensive Story of Seafaring from the Earliest Times to the Present Day. London: Conway Maritime Press. . *Wright, David Curtis. (2001) ''The History of China''. Westport: Greenwood Press. . *You, Zhanhong. "The Making Technique and Its Application in Military of Bow and Crossbow During Pre-Qin and Han Dynasty," in ''Journal of Tsinghua University'', Vol. 9, No. 3 (1994): 74–86. .


External links


Hunan Provincial Museum
(picture and description of the 2nd-century BCE
Mawangdui Mawangdui () is an archaeological site located in Changsha, China. The site consists of two saddle-shaped hills and contained the tombs of three people from the Changsha Kingdom during the western Han dynasty (206 BC – 9 AD): the Chancellor Li ...
garrison map)
"Ceramic Models of Wells in the Han Dynasty (206 BC to AD 220), China", by Jiu J. Jiao, University of Alabama
(pictures and description of Han architectural models) * {{DEFAULTSORT:Science And Technology Of The Han Dynasty Han dynasty History of science and technology in China, H Ancient Chinese science