Science and technology of the Tang Dynasty
Encyclopedia
The Tang Dynasty
(618 CE – 907 CE) of ancient China
witnessed many advancements in Chinese science and technology
, with various developments in woodblock printing
, timekeeping, mechanical engineering, medicine, structural engineering, cartography, and alchemy.
Woodblock printing
made the written word available to vastly greater audiences. One of the world's oldest surviving printed documents is a miniature Buddhist dharani
sutra
unearthed at Xi'an in 1974 and dated roughly from 650 to 670. The Diamond Sutra
is the first full-length book printed at regular size, complete with illustrations embedded with the text and dated precisely to 868. Among the earliest documents to be printed were Buddhist texts as well as calendars, the latter essential for calculating and marking which days were auspicious and which days were not. With so many books coming into circulation for the general public, literacy rates could improve, along with the lower classes being able to obtain cheaper sources of study. Therefore, there were more lower class people seen entering the Imperial Examinations and passing them by the later Song Dynasty. Although the later Bi Sheng
's movable type
printing
in the 11th century was innovative for his period, woodblock printing that became widespread in the Tang would remain the dominant printing type in China
until the more advanced printing press
from Europe
became widely accepted and used in East Asia. The first use of the playing card
during the Tang Dynasty was an auxiliary invention of the new age of printing.
(78-139) and Ma Jun
(fl. 3rd century) gave the Tang engineer, astronomer, and monk Yi Xing
(683-727) inspiration when he invented the world's first clockwork escapement
mechanism in 725. This was used alongside a clepsydra
clock and waterwheel to power a rotating armillary sphere
in representation of astronomical observation. Yi Xing's device also had a mechanically timed bell that was struck automatically every hour, and a drum that was struck automatically every quarter hour; essentially, a striking clock
. Yi Xing's astronomical clock
and water-powered armillary sphere became well known throughout the country, since students attempting to pass the imperial examinations by 730 had to write an essay on the device as an exam requirement. However, the most common type of public and palace timekeeping device was the inflow clepsydra. Its design was improved c. 610 by the Sui-dynasty engineers Geng Xun and Yuwen Kai. They provided a steelyard balance
that allowed seasonal adjustment in the pressure head
of the compensating tank and could then control the rate of flow for different lengths of day and night.
ed-wooden tortoise frame. This intricate device used a hydraulic pump that siphoned wine out of metal dragon
-headed faucets, as well as tilting bowls that were timed to dip wine down, by force of gravity when filled, into an artificial lake that had intricate iron leaves popping up as trays for placing party treats. Furthermore, as the historian Charles Benn describes it:
Although the use of a teasing mechanical puppet in this wine-serving device was certainly ingenious, the use of mechanical puppets in China date back to the Qin Dynasty
(221-207 BC) while Ma Jun
in the 3rd century had an entire mechanical puppet theater operated by the rotation of a waterwheel. There was also an automatic wine-server known in the ancient Greco-Roman world, a design of Heron of Alexandria that employed an urn with an inner valve and a lever device similar to the one described above. There are many stories of automaton
s used in the Tang, including general Yang Wulian's wooden statue of a monk who stretched his hands out to collect contributions; when the amount of coins reached a certain weight, the mechanical figure moved his arms to deposit them in a satchel. This weight-and-lever mechanism was exactly like Heron's penny slot machine
. Other devices included one by Wang Ju, whose "wooden otter" could allegedly catch fish; Needham suspects a spring trap
of some kind was employed here.
The Chinese of the Tang era were also very interested in the benefits of officially classifying all of the medicines
used in pharmacology
. In 657, Emperor Gaozong of Tang
(r. 649-683) commissioned the literary project of publishing an official materia medica
, complete with text and illustrated drawings for 833 different medicinal substances taken from different stones, minerals, metals, plants, herbs, animals, vegetables, fruits, and cereal crops. In addition to compiling pharmacopeias, the Tang fostered learning in medicine by upholding imperial medical colleges, state examinations for doctors, and publishing forensic manuals for physicians. Authors of medicine in the Tang include Zhen Qian (d. 643) and Sun Simiao
(581-682), the former who first identified in writing that patients with diabetes had an excess of sugar
in their urine
, and the latter who was the first to recognize that diabetic patients should avoid consuming alcohol and starch
y foods. As written by Zhen Qian and others in the Tang, the thyroid
glands of sheep and pigs were successfully used to treat goiters; thyroid extracts were not used to treat patients with goiter in the West until 1890.
, there were also government standard building codes, outlined in the early Tang book of the Yingshan Ling (National Building Law). Fragments of this book have survived in the Tang Lü (The Tang Code), while the Song Dynasty architectural manual of the Yingzao Fashi
(State Building Standards) by Li Jie (1065–1101) in 1103 is the oldest existing technical treatise on Chinese architecture that has survived in full. During the reign of Emperor Xuanzong of Tang
(712-756) there were 34,850 registered craftsmen serving the state, managed by the Agency of Palace Buildings (Jingzuo Jian).
, there were further advances beyond the map-makers of the Han Dynasty. When the Tang chancellor Pei Ju
(547-627) was working for the Sui Dynasty as a Commercial Commissioner in 605, he created a well-known gridded map with a graduated scale
in the tradition of Pei Xiu
(224-271). The Tang chancellor Xu Jingzong
(592-672) was also known for his map of China drawn in the year 658. In the year 785 the Emperor Dezong
had the geographer and cartographer Jia Dan
(730-805) complete a map of China and her former colonies in Central Asia. Upon its completion in 801, the map was 9.1 m (30 ft) in length and 10 m (33 ft) in height, mapped out on a grid scale of one inch equaling one hundred li
(Chinese unit of measuring distance). A Chinese map of 1137 is similar in complexity to the one made by Jia Dan, carved on a stone stele with a grid scale of 100 li. However, the only type of map that has survived from the Tang period are star chart
s. Despite this, the earliest extant terrain maps of China come from the ancient State of Qin
; maps from the 4th century BC that were excavated in 1986.
The Chinese of the Tang period employed complex chemical formulas for an array of different purposes, often found through experiments of alchemy
. These included a waterproof and dust-repelling cream or varnish
for clothes and weapons, fireproof
cement
for glass and porcelain wares, a waterproof cream applied to silk clothes of underwater divers
, a cream designated for polishing bronze mirrors, and many other useful formulas. The vitrified, translucent ceramic known as porcelain
was invented in China during the Tang, although many types of glazed ceramics preceded it.
Ever since the Han Dynasty
(202 BC - 220 AD), the Chinese had drilled deep borehole
s to transport natural gas
from bamboo pipelines
to stoves where cast iron
evaporation pans boiled brine
to extract salt
. During the Tang Dynasty, a gazetteer
of Sichuan province stated that at one of these 182 m (600 ft) 'fire wells', men collected natural gas into portable bamboo tubes which could be carried around for dozens of km (mi) and still produce a flame. These were essentially the first gas cylinder
s; Robert Temple assumes some sort of tap
was used for this device.
The inventor Ding Huan (fl.
180 AD) of the Han Dynasty invented a rotary fan
for air conditioning
, with seven wheels 3 m (10 ft) in diameter and manually powered. In 747, Emperor Xuanzong had a "Cool Hall" built in the imperial palace, which the Tang Yulin (唐語林) describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song Dynasty, written sources mentioned the air conditioning rotary fan as even more widely used.
Tang Dynasty
The Tang Dynasty was an imperial dynasty of China preceded by the Sui Dynasty and followed by the Five Dynasties and Ten Kingdoms Period. It was founded by the Li family, who seized power during the decline and collapse of the Sui Empire...
(618 CE – 907 CE) of ancient China
History of China
Chinese civilization originated in various regional centers along both the Yellow River and the Yangtze River valleys in the Neolithic era, but the Yellow River is said to be the Cradle of Chinese Civilization. With thousands of years of continuous history, China is one of the world's oldest...
witnessed many advancements in Chinese science and technology
History of science and technology in China
The history of science and technology in China is both long and rich with many contributions to science and technology. In antiquity, independently of other civilizations, ancient Chinese philosophers made significant advances in science, technology, mathematics, and astronomy...
, with various developments in woodblock printing
Woodblock printing
Woodblock printing is a technique for printing text, images or patterns used widely throughout East Asia and originating in China in antiquity as a method of printing on textiles and later paper....
, timekeeping, mechanical engineering, medicine, structural engineering, cartography, and alchemy.
Woodblock printing
Woodblock printing
Woodblock printing is a technique for printing text, images or patterns used widely throughout East Asia and originating in China in antiquity as a method of printing on textiles and later paper....
made the written word available to vastly greater audiences. One of the world's oldest surviving printed documents is a miniature Buddhist dharani
Dharani
A ' is a type of ritual speech similar to a mantra. The terms dharani and satheesh may be seen as synonyms, although they are normally used in distinct contexts....
sutra
Sutra
Sūtra is an aphorism or a collection of such aphorisms in the form of a manual. Literally it means a thread or line that holds things together and is derived from the verbal root siv-, meaning to sew , as does the medical term...
unearthed at Xi'an in 1974 and dated roughly from 650 to 670. The Diamond Sutra
Diamond Sutra
The Diamond Sūtra , is a short and well-known Mahāyāna sūtra from the Prajñāpāramitā, or "Perfection of Wisdom" genre, and emphasizes the practice of non-abiding and non-attachment...
is the first full-length book printed at regular size, complete with illustrations embedded with the text and dated precisely to 868. Among the earliest documents to be printed were Buddhist texts as well as calendars, the latter essential for calculating and marking which days were auspicious and which days were not. With so many books coming into circulation for the general public, literacy rates could improve, along with the lower classes being able to obtain cheaper sources of study. Therefore, there were more lower class people seen entering the Imperial Examinations and passing them by the later Song Dynasty. Although the later Bi Sheng
Bi Sheng
Bì Shēng was the inventor of the first known movable type technology. Bi Sheng's system was made of Chinese porcelain and was invented between 1041 and 1048 in China.-Movable type printing:...
's movable type
Movable type
Movable type is the system of printing and typography that uses movable components to reproduce the elements of a document ....
printing
Printing
Printing is a process for reproducing text and image, typically with ink on paper using a printing press. It is often carried out as a large-scale industrial process, and is an essential part of publishing and transaction printing....
in the 11th century was innovative for his period, woodblock printing that became widespread in the Tang would remain the dominant printing type in China
History of typography in East Asia
The history of printing in East Asia refers to the use of woodblock printing and movable type printing by East Asian artisans. The former existed in Tang China as early as the 7th century, and the latter in Song China by the 11th century. Use of woodblock printing quickly spread to other East Asian...
until the more advanced printing press
Printing press
A printing press is a device for applying pressure to an inked surface resting upon a print medium , thereby transferring the ink...
from Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
became widely accepted and used in East Asia. The first use of the playing card
Playing card
A playing card is a piece of specially prepared heavy paper, thin cardboard, plastic-coated paper, cotton-paper blend, or thin plastic, marked with distinguishing motifs and used as one of a set for playing card games...
during the Tang Dynasty was an auxiliary invention of the new age of printing.
Clockworks and timekeeping
Technology during the Tang period was built also upon the precedents of the past. The mechanical gear systems of Zhang HengZhang Heng
Zhang Heng was a Chinese astronomer, mathematician, inventor, geographer, cartographer, artist, poet, statesman, and literary scholar from Nanyang, Henan. He lived during the Eastern Han Dynasty of China. He was educated in the capital cities of Luoyang and Chang'an, and began his career as a...
(78-139) and Ma Jun
Ma Jun
Ma Jun , style name Deheng , was a Chinese mechanical engineer and government official during the Three Kingdoms era of China...
(fl. 3rd century) gave the Tang engineer, astronomer, and monk Yi Xing
Yi Xing
Yi Xing , born Zhang Sui , was a Chinese astronomer, mathematician, mechanical engineer,and Buddhist monk of the Tang Dynasty...
(683-727) inspiration when he invented the world's first clockwork escapement
Escapement
In mechanical watches and clocks, an escapement is a device that transfers energy to the timekeeping element and enables counting the number of oscillations of the timekeeping element...
mechanism in 725. This was used alongside a clepsydra
Water clock
A water clock or clepsydra is any timepiece in which time is measured by the regulated flow of liquid into or out from a vessel where the amount is then measured.Water clocks, along with sundials, are likely to be the oldest time-measuring instruments, with the only exceptions...
clock and waterwheel to power a rotating armillary sphere
Armillary sphere
An armillary sphere is a model of objects in the sky , consisting of a spherical framework of rings, centred on Earth, that represent lines of celestial longitude and latitude and other astronomically important features such as the ecliptic...
in representation of astronomical observation. Yi Xing's device also had a mechanically timed bell that was struck automatically every hour, and a drum that was struck automatically every quarter hour; essentially, a striking clock
Striking clock
A striking clock is a clock that sounds the hours audibly on a bell or gong. In 12 hour striking, used most commonly in striking clocks today, the clock strikes once at 1 AM, twice at 2 AM, continuing in this way up to twelve times at 12 noon, then starts over, striking once at 1 PM, twice at 2...
. Yi Xing's astronomical clock
Astronomical clock
An astronomical clock is a clock with special mechanisms and dials to display astronomical information, such as the relative positions of the sun, moon, zodiacal constellations, and sometimes major planets.-Definition:...
and water-powered armillary sphere became well known throughout the country, since students attempting to pass the imperial examinations by 730 had to write an essay on the device as an exam requirement. However, the most common type of public and palace timekeeping device was the inflow clepsydra. Its design was improved c. 610 by the Sui-dynasty engineers Geng Xun and Yuwen Kai. They provided a steelyard balance
Steelyard balance
A steelyard balance or steelyard is a straight-beam balance with arms of unequal length. It incorporates a counterweight which slides along the calibrated longer arm to counterbalance the load and indicate its weight...
that allowed seasonal adjustment in the pressure head
Pressure head
Pressure head is a term used in fluid mechanics to represent the internal energy of a fluid due to the pressure exerted on its container. It may also be called static pressure head or simply static head...
of the compensating tank and could then control the rate of flow for different lengths of day and night.
Mechanical delights and automatons
There were many other mechanical inventions during the Tang era. This included a 0.91 m (3 ft) tall mechanical wine server of the early 8th century that was in the shape of an artificial mountain, carved out of iron and rested on a lacquerLacquer
In a general sense, lacquer is a somewhat imprecise term for a clear or coloured varnish that dries by solvent evaporation and often a curing process as well that produces a hard, durable finish, in any sheen level from ultra matte to high gloss and that can be further polished as required...
ed-wooden tortoise frame. This intricate device used a hydraulic pump that siphoned wine out of metal dragon
Chinese dragon
Chinese dragons are legendary creatures in Chinese mythology and folklore, with mythic counterparts among Japanese, Korean, Vietnamese, Bhutanese, Western and Turkic dragons. In Chinese art, dragons are typically portrayed as long, scaled, serpentine creatures with four legs...
-headed faucets, as well as tilting bowls that were timed to dip wine down, by force of gravity when filled, into an artificial lake that had intricate iron leaves popping up as trays for placing party treats. Furthermore, as the historian Charles Benn describes it:
Qin Dynasty
The Qin Dynasty was the first imperial dynasty of China, lasting from 221 to 207 BC. The Qin state derived its name from its heartland of Qin, in modern-day Shaanxi. The strength of the Qin state was greatly increased by the legalist reforms of Shang Yang in the 4th century BC, during the Warring...
(221-207 BC) while Ma Jun
Ma Jun
Ma Jun , style name Deheng , was a Chinese mechanical engineer and government official during the Three Kingdoms era of China...
in the 3rd century had an entire mechanical puppet theater operated by the rotation of a waterwheel. There was also an automatic wine-server known in the ancient Greco-Roman world, a design of Heron of Alexandria that employed an urn with an inner valve and a lever device similar to the one described above. There are many stories of automaton
Automaton
An automaton is a self-operating machine. The word is sometimes used to describe a robot, more specifically an autonomous robot. An alternative spelling, now obsolete, is automation.-Etymology:...
s used in the Tang, including general Yang Wulian's wooden statue of a monk who stretched his hands out to collect contributions; when the amount of coins reached a certain weight, the mechanical figure moved his arms to deposit them in a satchel. This weight-and-lever mechanism was exactly like Heron's penny slot machine
Slot machine
A slot machine , informally fruit machine , the slots , poker machine or "pokies" or simply slot is a casino gambling machine with three or more reels which spin when a button is pushed...
. Other devices included one by Wang Ju, whose "wooden otter" could allegedly catch fish; Needham suspects a spring trap
Spring (device)
A spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication...
of some kind was employed here.
Medicine
Traditional Chinese medicine
Traditional Chinese Medicine refers to a broad range of medicine practices sharing common theoretical concepts which have been developed in China and are based on a tradition of more than 2,000 years, including various forms of herbal medicine, acupuncture, massage , exercise , and dietary therapy...
used in pharmacology
Pharmacology
Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...
. In 657, Emperor Gaozong of Tang
Emperor Gaozong of Tang
Emperor Gaozong of Tang , personal name Li Zhi , was the third emperor of the Tang Dynasty in China, ruling from 649 to 683...
(r. 649-683) commissioned the literary project of publishing an official materia medica
Materia medica
Materia medica is a Latin medical term for the body of collected knowledge about the therapeutic properties of any substance used for healing . The term 'materia medica' derived from the title of a work by the Ancient Greek physician Pedanius Dioscorides in the 1st century AD, De materia medica libre...
, complete with text and illustrated drawings for 833 different medicinal substances taken from different stones, minerals, metals, plants, herbs, animals, vegetables, fruits, and cereal crops. In addition to compiling pharmacopeias, the Tang fostered learning in medicine by upholding imperial medical colleges, state examinations for doctors, and publishing forensic manuals for physicians. Authors of medicine in the Tang include Zhen Qian (d. 643) and Sun Simiao
Sun Simiao
Sun Simiao was a famous traditional Chinese medicine doctor of the Sui and Tang dynasty. He was titled as China's King of Medicine for his significant contributions to Chinese medicine and tremendous care to his patients....
(581-682), the former who first identified in writing that patients with diabetes had an excess of sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...
in their urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
, and the latter who was the first to recognize that diabetic patients should avoid consuming alcohol and starch
Starch
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...
y foods. As written by Zhen Qian and others in the Tang, the thyroid
Thyroid
The thyroid gland or simply, the thyroid , in vertebrate anatomy, is one of the largest endocrine glands. The thyroid gland is found in the neck, below the thyroid cartilage...
glands of sheep and pigs were successfully used to treat goiters; thyroid extracts were not used to treat patients with goiter in the West until 1890.
Structural engineering
In the realm of technical Chinese architectureChinese architecture
Chinese architecture refers to a style of architecture that has taken shape in East Asia over many centuries. The structural principles of Chinese architecture have remained largely unchanged, the main changes being only the decorative details...
, there were also government standard building codes, outlined in the early Tang book of the Yingshan Ling (National Building Law). Fragments of this book have survived in the Tang Lü (The Tang Code), while the Song Dynasty architectural manual of the Yingzao Fashi
Yingzao Fashi
The Yingzao Fashi is a technical treatise on architecture and craftsmanship written by the Chinese author Li Jie , the Directorate of Buildings and Construction during the mid Song Dynasty of China. A promising architect, he revised many older treatises on architecture from 1097 to 1100...
(State Building Standards) by Li Jie (1065–1101) in 1103 is the oldest existing technical treatise on Chinese architecture that has survived in full. During the reign of Emperor Xuanzong of Tang
Emperor Xuanzong of Tang
Emperor Xuanzong of Tang , also commonly known as Emperor Ming of Tang , personal name Li Longji , known as Wu Longji from 690 to 705, was the seventh emperor of the Tang dynasty in China, reigning from 712 to 756. His reign of 43 years was the longest during the Tang Dynasty...
(712-756) there were 34,850 registered craftsmen serving the state, managed by the Agency of Palace Buildings (Jingzuo Jian).
Cartography
In the realm of cartographyCartography
Cartography is the study and practice of making maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively.The fundamental problems of traditional cartography are to:*Set the map's...
, there were further advances beyond the map-makers of the Han Dynasty. When the Tang chancellor Pei Ju
Pei Ju
Pei Ju , courtesy name Hongda , formally Duke Jing of Anyi , was a high level official during the Chinese dynasties Sui Dynasty and Tang Dynasty, briefly serving as a chancellor during the reign of Emperor Gaozu of Tang...
(547-627) was working for the Sui Dynasty as a Commercial Commissioner in 605, he created a well-known gridded map with a graduated scale
Scale (map)
The scale of a map is defined as the ratio of a distance on the map to the corresponding distance on the ground.If the region of the map is small enough for the curvature of the Earth to be neglected, then the scale may be taken as a constant ratio over the whole map....
in the tradition of Pei Xiu
Pei Xiu
Pei Xiu , style name Jiyan , was a minister, geographer, and cartographer of the state of Cao Wei during the Three Kingdoms period of Chinese history, as well as the subsequent Jin Dynasty. Pei Xiu was very much trusted by Sima Zhao, and participated in the suppression of Zhuge Dan's coup...
(224-271). The Tang chancellor Xu Jingzong
Xu Jingzong
Xu Jingzong , courtesy name Yanzu , formally Duke Gong of Gaoyang , was a chancellor of the Chinese dynasty Tang Dynasty...
(592-672) was also known for his map of China drawn in the year 658. In the year 785 the Emperor Dezong
Emperor Dezong of Tang
Emperor Dezong of Tang , personally name Li Kuo , was an emperor of the Chinese Tang Dynasty and the oldest son of his father Emperor Daizong. His reign of 26 years was the third longest in the Tang dynasty...
had the geographer and cartographer Jia Dan
Jia Dan
Jia Dan , courtesy name Dunshi , formally Duke Yuanjing of Wei , was a Chinese scholar-official, general, geographer, and cartographer from Cangzhou, Hebei during the Tang Dynasty of China.- Background :...
(730-805) complete a map of China and her former colonies in Central Asia. Upon its completion in 801, the map was 9.1 m (30 ft) in length and 10 m (33 ft) in height, mapped out on a grid scale of one inch equaling one hundred li
Li (unit)
The li is a traditional Chinese unit of distance, which has varied considerably over time but now has a standardized length of 500 meters or half a kilometer...
(Chinese unit of measuring distance). A Chinese map of 1137 is similar in complexity to the one made by Jia Dan, carved on a stone stele with a grid scale of 100 li. However, the only type of map that has survived from the Tang period are star chart
Star chart
A star chart is a map of the night sky. Astronomers divide these into grids to use them more easily. They are used to identify and locate astronomical objects such as stars, constellations and galaxies. They have been used for human navigation since time immemorial...
s. Despite this, the earliest extant terrain maps of China come from the ancient State of Qin
Qin (state)
The State of Qin was a Chinese feudal state that existed during the Spring and Autumn and Warring States Periods of Chinese history...
; maps from the 4th century BC that were excavated in 1986.
Alchemy, gas cylinders, and air conditioning
Alchemy
Alchemy is an influential philosophical tradition whose early practitioners’ claims to profound powers were known from antiquity. The defining objectives of alchemy are varied; these include the creation of the fabled philosopher's stone possessing powers including the capability of turning base...
. These included a waterproof and dust-repelling cream or varnish
Varnish
Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...
for clothes and weapons, fireproof
Fireproof
-Track List for Original 2002 Release:# "Fireproof" – 3:46# "Just 2 Get By" – 4:17# "Echelon" – 3:25# "Stay Up" – 3:40# "Behind Closed Doors" – 2:55# "Epidemic" – 3:14# "Hindsight" – 2:57# "Light at My Feet" – 3:28# "A Shame" – 3:17...
cement
Cement
In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...
for glass and porcelain wares, a waterproof cream applied to silk clothes of underwater divers
Underwater diving
Underwater diving is the practice of going underwater, either with breathing apparatus or by breath-holding .Recreational diving is a popular activity...
, a cream designated for polishing bronze mirrors, and many other useful formulas. The vitrified, translucent ceramic known as porcelain
Porcelain
Porcelain is a ceramic material made by heating raw materials, generally including clay in the form of kaolin, in a kiln to temperatures between and...
was invented in China during the Tang, although many types of glazed ceramics preceded it.
Ever since the Han Dynasty
Han Dynasty
The Han Dynasty was the second imperial dynasty of China, preceded by the Qin Dynasty and succeeded by the Three Kingdoms . It was founded by the rebel leader Liu Bang, known posthumously as Emperor Gaozu of Han. It was briefly interrupted by the Xin Dynasty of the former regent Wang Mang...
(202 BC - 220 AD), the Chinese had drilled deep borehole
Borehole
A borehole is the generalized term for any narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water or other liquid or gases , as part of a geotechnical investigation, environmental site...
s to transport natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
from bamboo pipelines
Pipeline transport
Pipeline transport is the transportation of goods through a pipe. Most commonly, liquids and gases are sent, but pneumatic tubes that transport solid capsules using compressed air are also used....
to stoves where cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...
evaporation pans boiled brine
Brine
Brine is water, saturated or nearly saturated with salt .Brine is used to preserve vegetables, fruit, fish, and meat, in a process known as brining . Brine is also commonly used to age Halloumi and Feta cheeses, or for pickling foodstuffs, as a means of preserving them...
to extract salt
Salt
In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...
. During the Tang Dynasty, a gazetteer
Gazetteer
A gazetteer is a geographical dictionary or directory, an important reference for information about places and place names , used in conjunction with a map or a full atlas. It typically contains information concerning the geographical makeup of a country, region, or continent as well as the social...
of Sichuan province stated that at one of these 182 m (600 ft) 'fire wells', men collected natural gas into portable bamboo tubes which could be carried around for dozens of km (mi) and still produce a flame. These were essentially the first gas cylinder
Gas cylinder
A gas cylinder is a pressure vessel used to store gases at above atmospheric pressure. High pressure gas cylinders are also called bottles. Although they are sometimes colloquially called "tanks", this is technically incorrect, as a tank is a vessel used to store liquids at ambient pressure and...
s; Robert Temple assumes some sort of tap
Tap (valve)
A tap is a valve controlling release of liquids or gas. In the British Isles and most of the Commonwealth, the word is used for any everyday type of valve, particularly the fittings that control water supply to bathtubs and sinks. In the U.S., the term "tap" is more often used for beer taps,...
was used for this device.
The inventor Ding Huan (fl.
Floruit
Floruit , abbreviated fl. , is a Latin verb meaning "flourished", denoting the period of time during which something was active...
180 AD) of the Han Dynasty invented a rotary fan
Fan (mechanical)
A mechanical fan is a machine used to create flow within a fluid, typically a gas such as air.A fan consists of a rotating arrangement of vanes or blades which act on the air. Usually, it is contained within some form of housing or case. This may direct the airflow or increase safety by preventing...
for air conditioning
Air conditioning
An air conditioner is a home appliance, system, or mechanism designed to dehumidify and extract heat from an area. The cooling is done using a simple refrigeration cycle...
, with seven wheels 3 m (10 ft) in diameter and manually powered. In 747, Emperor Xuanzong had a "Cool Hall" built in the imperial palace, which the Tang Yulin (唐語林) describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song Dynasty, written sources mentioned the air conditioning rotary fan as even more widely used.