China began to make jade objects during the New Stone Age, 7,000 years ago. A jade dragon made after carving and grinding from a single piece of dark green jade unearthed in Chifeng, in the Inner Mongolia Autonomous Region, in 1971 is a shiny object in the shape of a dragon's body, curved like a C. On the back of the dragon is a small hole through which a string can pass so that the piece can be hung up. The highly expressive dragon was shaped using the methods of sculpture-in-the-round and relief.

Among the funerary objects belonging to the Liangzhu Culture of the New Stone Age, some 6,000 years ago, is a square cylinder made of jade. This superbly processed item is marked off into nineteen sections. Studies suggest that that it was either a ritual object for sacrificial ceremonies or a burial object. A recent deduction was offered by Nobel laureate C. N. Yang, who believes that jade objects like this were used by the ancient Chinese as tools to observe the sky.

In 1976, the excavation of a tomb in Anyang, Henan Province, belonging to a noblewoman who lived more than 3,000 years ago caused a sensation in archaeological circles. According to written records, Fu Hao, the owner of the tomb, was a woman general and wife of Wu Ding, king of Shang. The tomb yielded a large amount of arms made of bronze, which proves that during the Shang Dynasty (16th-11th centuries BC), soldiers were already armed with bronze weapons.

The Chinese began to smelt bronze in the Xia Dynasty (21st-16th centuries BC). About 5,000 years ago, people began to extract brass from ore to make small objects with the cold-forging technique. Then they added a certain percentage of tin to lower the melting point and increase solidity. Tin gave brass a bluish tinge, and the alloy became known as bronze, which in Chinese simply means bluish copper. In the Shang Dynasty, bronze smelting became the most important branch of the handicraft industries. Shang bronzes come in many varieties, chiefly ritual objects, wine vessels, weapons, musical instruments and food containers. Many ritual bronzes were engraved with records of the military exploits of rulers, which are extremely valuable for historical research. Bronze working reached its prime in the Spring and Autumn Period, which covered the period from 770 to 476 BC, with the creation of the lost-wax method. This method used easy-melting wax sprinkled with fine mud and refractory materials. When the wax solidified, it was made into molds. After baking, the wax melted and flowed away, creating a vacuum which was filled with bronze liquid to eventually produce a bronze ware item. The tripod which Wang Ziwu, son of the prince of Chu, offered when he prayed for longevity is regarded as one of the first bronze wares made with the lost-wax method.

During the Shang Dynasty, Chinese people began to learn to use iron. The iron-edged bronze sword unearthed at Liujiahe Village in Pinggu, Beijing, is one of the earliest iron-containing objects discovered in China. The iron blade was cast from smelted meteorite iron, and then inlaid into the bronze handle. The sword is testimony to the fact that people had mastered the fairly advanced technique of iron smelting and casting iron with bronze.

Iron smelting technology made breakthroughs during the Warring States Period (475-221 BC). Technologies for cast-iron forging, and carburized bronze from "block iron" showed a marked improvement. Malleable cast iron products show greater hardness and better ductility. An iron mold from the Warring States Period excavated in Xinglong, Hebei Province, was a standard white-iron casting instrument.

Qin, a ducal state of the Warring States Period, experienced speedy development of productivity. Bronze pliers unearthed in Fengxiang, Shaanxi Province, previously part of the State of Qin, are very similar to the same type of tools used today.

Handicrafts such as lacquer, textiles, leather processing, jade carving and the making of gold and silver wares all achieved great progress during the Warring States Period. In the late years of this period, the art of adding a metal edge to the mouth, middle part and lower end of lacquer wares not only increased the durability of the objects but also had a highly decorative effect, making lacquer wares more valuable.

Iron smelting in the Han Dynasty (206 BC-AD 220) made further progress, as indicated by the appearance of various kinds of furnaces, the use of refractory materials and bellows which were made of leather and powered by human strength. Bellows drastically increased the temperature of the furnace, and further promoted metallurgy.

The Han Dynasty yielded another highly valuable cultural relic-bronze calipers carved with the year when they were made. In order to measure things, one simply pulled a ring on the movable part to change the gauge. Very similar to the modern vernier calipers, it is the earliest such measuring instrument found in the world to date and valuable material for the study of the science of measurement and the ancient history of mathematics.

Carts and boats were the two major types of transportation in ancient times. Horse-drawn carriages of the Han Dynasty showed great improvements in both appearance and construction techniques. Carriages in the Shang and Zhou dynasties had two wheels but one shaft while those of the Warring States Period acquired two shafts. By the Eastern Han Dynasty, double-shaft horse-drawn carriages had become very common. The pottery carriage excavated at Yangzi Hill in Chengdu, Sichuan, in 1954 is rectangular in shape, and has a canopy which, in the real thing, could be rolled up. The two shafts are straight but the ends are S-shaped.

Depictions of horse-drawn carriages with a great variety of shapes and appearances have been found on Han Dynasty brick and stone carvings. A stone carving with vivid images of carriage wheels has been excavated at Jiaxiang, Shandong Province.

The fact that Han Dynasty carriages could carry heavy loads, as they often could accommodate four to five people each, was largely due to the advanced harness used. Studies of the history of the harness have shown that in 1,000 BC, Europeans used the throat-and-girth harness, which did not allow beasts of burden to pull a weight of more than 500 kg. The reason was that the animal's neck could only withstand so much pressure.

In the early Han Dynasty, around 200 BC, China already had the breast-harness, which allowed the animal to breathe easily while pulling heavier loads. In the 11th century, the yoke was introduced to Europe from China, which enabled horses to pull plows instead of physically weaker cattle, greatly facilitating agricultural production in Europe.

The single-wheel barrow invented in the early days of the Eastern Han had a simple structure, was easy to handle and could be used on flat surfaces, hilly areas or narrow paths. It could carry both people and cargo, making it an economical and practical means of transportation at the time. The barrow marked an important invention in the history of transportation in China. This type of barrow is still in use in some areas of China.

In the Jin Dynasty (265-420) a kind of odometer was used on carriages. It was a wooden figure connected to the wheels by a series of gears, and which beat a drum to indicate the distance covered. The wheels had a circumference of five meters, and so with every 100 revolutions the carriage had covered 500 meters, and the figure would strike its drum.

China led the world in shipbuilding in ancient times. Canoes first appeared during the period of primitive society, and large warships were made during the Spring and Autumn and Warring States periods. Shipbuilding technology made breakthroughs during the Han Dynasty, as evidenced by the invention and application of helms and anchors. An Eastern Han pottery boat unearthed at Xianlie Road, Guangzhou, 1954, shows that the helm was installed in the stern. Underneath the bow of the ship hangs a Y-shaped anchor, which would have been made of stone for a real ship. These technological improvements raised the navigational accuracy and safety levels when the ship was sailing and stability when it anchored.

The first mechanical crossbow appeared during the Spring and Autumn period, and this type of weapon grew in popularity during the Han and Jin periods. Some of the mechanical devices on crossbows of the Han Dynasty bear marks which allowed the archer to take aim by following the appropriate mark. This helped raise accuracy. In 1979, such a mechanical device was excavated in Zibo, Shandong. The gilded parts on the device, which was a burial object in the tomb of Duke Liu Xiang, indicate that the original owner of the crossbow was a man of unusually high social status.

The tradition of having jade burial objects goes back a long way in ancient China, and jade objects had been found in tombs of the New Stone Age. The tradition became more fashionable during the Han Dynasty. Apart from traditional concepts at work, perhaps another reason for this custom was the habit of elaborate burials and superstitious practices. People at the time believed that jade could prevent the corpse decaying and hence ensure the chance for rebirth. As a result, jade burial suits made by linking up jade pieces with metal or silk thread were prepared for emperors and his empresses as well as some of the nobility in the Han Dynasty. According to the volume on rituals in the History of the Later Han Dynasty, the burial suits for dead emperors were sown with gold thread, those for the princes, first-generation dukes and marquises, nobles and princesses were woven with silver thread, while those of the sons of the first-generation nobles and daughters of princes, with copper thread. Silk thread was used for the grave clothes of people of subordinate ranks. Ordinary officials and the common people were forbidden to have jade burial clothes.

The jade burial suit belonging to Prince Huai of the Western Han Dynasty, unearthed in Dingxian, Hebei, in 1973, was made with a total of 1,203 pieces of jade and 2,580 grams of gold thread. The suit consists of parts for the head, body, arms, legs and feet. The jade pieces are in trapezoid, rectangular, square and triangular shapes. All of them were well ground and polished, reflecting advanced jade carving techniques.

Zhang Heng was the leading scientist of the Eastern Han period (25-220). In 132, he built the world's first seismograph. The original of the device has long been lost, but based on the volume on Zhang Heng in the History of the Later Han Dynasty and archaeological research findings, Mr. Wang Zhenduo reconstructed Zhang Heng's seismograph in 1951.

The seismograph looked like a huge wine jar with a diameter of 1.9 meters. Eight dragon figures representing the eight directions (east, west, north, south, northeast, northwest, southeast and southwest) were arranged on the outside of the jar. In the mouth of each dragon was a small bronze ball, and underneath each dragon's head was a toad with its mouth gaping upwards. In the center of the seismograph was a sort of pendulum, surrounding which were eight groups of lever mechanisms distributed in the eight directions and connected to the mouths of the dragons. If a tremor occurred in any direction and seismic waves were transmitted to the seismograph, the pendulum would incline to one direction and trigger a lever in the dragon's head. The dragon would then open its mouth, and release its bronze ball, which would fall into the mouth of the toad underneath. Thus, the direction in which the earthquake had occurred was known. Making clever use of the mechanical theory of inertia, the seismograph had a high degree of sensitivity. According to the History of the Later Han Dynasty, one day in 138 the dragon in the west direction spit out its bronze ball, but people did not feel any tremor. Several days later, however, a horseman galloped to the capital, bringing the news that an earthquake had struck Longxi, in western Gansu Province, some 500 kilometers from the capital city of Luoyang. This anecdote is evidence that the seismograph was not only very sensitive, but also accurate.

Zhang Heng's seismograph was 1,700 years earlier than similar devices built in Europe, demonstrating ancient China's advanced level in earthquake studies.

From the 1st to the 3rd centuries, ethnic minorities in China's north and northwest gradually migrated southward to areas south of the Great Wall and along the Yellow River. Among them were the Xiongnu, Xianbei, Jie, Di and Qiang tribes. North China's tribal people were good at riding and shooting from horseback. Under their influence, the Han people saw increasing sophistication of their horse gear, particularly with the appearance of double stirrups. Two gilded bronze stirrups which were unearthed in Beipiao, Liaoning, in 1965 are in the shape of round triangles with long perforated handles. The stirrups were made of mulberry wood in a triangular shape, with triangular wood pegs to facilitate steadying the feet while riding. The surface of the stirrups is covered in gilded bronze. With improved horse gear, cavalrymen found it easier to control and tame horses, gaining greater flexibility for fighting on horseback.

People have commented that a handful of inventions, such as stirrups, which were so simple exerted an enormously catalytic impact on the history of mankind. Joseph Needham, once a professor at Cambridge University and a specialist in China's history of science, believed that stirrups allowed the rider and the horse to form an entity, greatly facilitating the cavalry charge. Once stirrups were introduced to Europe, they soon helped the class of knights to stabilize the feudal system.

From the 3rd to the 6th centuries, iron smelting made further progress, as it became possible to mix cast and wrought iron together. Copper-iron so smelted could be used to produce swords, but more often than not, it was used to make production tools and daily life utensils, greatly facilitating people's production activities and daily life.

The Zhaozhou Bridge, which was built during the Sui Dynasty (581-618) and is still in use today, is one of the architectural wonders that artisans of ancient times have left us. The single-arch bridge, 50.82 m long and 9.8 m wide, stretches from north to south over a span of 37.37 meters. Its low arch and gentle surface made it easy for both vehicles and pedestrians to cross. On each side of the arch are two small spandrel holes, which reduce the weight of the bridge, but also divert floodwaters and save building materials. They also add to the elegant appearance of the bridge.

The Tang Dynasty (618-907) has left us a treasure trove of splendid gold and silver wares. At the time, simple lathes were used for cutting and polishing. Many complicated industrial processing arts, including metal shaping, were employed. The patterns on the wares were meticulously executed and covered a wide range of subjects with strong influence from foreign cultures. Brass mirrors of the Tang Dynasty are highly representative in their shapes and decoration methods. Increasing amounts of silver and tin were used in the brass alloy. The surface of the mirrors is shiny and smooth. On the basis of highly developed mirror making technology, artisans in the Tang Dynasty used optical theory to successfully produce mirror-like implements used to generate fire from the sun, which was an unusual invention 1,300 years ago.