<P> Within the Liao Empire, the Jurchen tribes revolted against their overlords to establish the Jin dynasty in 1115 . In 1125, the devastating Jin cataphract annihilated the Liao dynasty, while remnants of Liao court members fled to Central Asia to found the Qara Khitai Empire (Western Liao Dynasty). Jin's invasion of the Song dynasty followed swiftly . In 1127, Kaifeng was sacked, a massive catastrophe known as the Jingkang Incident, ending the Northern Song Dynasty . Later the entire north of China was conquered . The survived members of Song court regrouped in the new capital city of Hangzhou, and initiated the Southern Song dynasty, which ruled territories south of the Huai River . In the ensuing years, the territory and population of China were divided between the Song dynasty, the Jin dynasty and the Western Xia dynasty . The era ended with the Mongol conquest, as Western Xia fell in 1227, the Jin dynasty in 1234, and finally the Southern Song dynasty in 1279 . </P> <P> Despite its military weakness, the Song dynasty is widely considered to be the high point of classical Chinese civilization . The Song economy, facilitated by technology advancement, had reached a level of sophistication probably unseen in world history before its time . The population soared to over 100 million and the living standards of common people improved tremendously due to improvements in rice cultivation and the wide availability of coal for production . The capital cities of Kaifeng and subsequently Hangzhou were both the most populous cities in the world for their time, and encouraged vibrant civil societies unmatched by previous Chinese dynasties . As land trading routes to far west were blocked by nomadic empires, there were extensive maritime trade with neighbouring states, which facilitated the use of Song coinage as the de facto currency of exchange . Giant wooden vessels equipped with compasses travelled throughout the China Seas and northern Indian Ocean . The concept of insurance was practised by merchants to hedge the risks of such long - haul maritime shipments . With prosperous economic activities, the historically first use of paper currency emerged in the western city of Chengdu, as a supplement to the existing copper coins . </P> <P> The Song Dynasty was considered to be the golden age of great advancements in science and technology of China, thanks to innovative scholar - officials such as Su Song (1020--1101) and Shen Kuo (1031--1095). Inventions such as the hydro - mechanical astronomical clock, the first continuous and endless power - transmitting chain, woodblock printing and paper money were all invented during the Song Dynasty . </P> <P> There was court intrigue between the political reformers and conservatives, led by the chancellors Wang Anshi and Sima Guang, respectively . By the mid-to - late 13th century, the Chinese had adopted the dogma of Neo-Confucian philosophy formulated by Zhu Xi . Enormous literary works were compiled during the Song dynasty, such as the historical work, the Zizhi Tongjian ("Comprehensive Mirror to Aid in Government"). The invention of movable - type printing further facilitated the spread of knowledge . Culture and the arts flourished, with grandiose artworks such as Along the River During the Qingming Festival and Eighteen Songs of a Nomad Flute, along with great Buddhist painters such as the prolific Lin Tinggui . </P>

Beginning in 1200 b.c.e. what new technology entered china