The First Oil Wells. The Chinese have used oil and gas for many centuries. There is no record of when Chinese began using natural gas, but clearly in Szechuan the local people were drilling down hundreds of feet into the earth to get natural gas and brine before the start of the Han Dynasty, before 400 B.C. The Chinese used bamboo pipelines to carry natural gas and mix it with air to yield a usable source of fuel for fires. The initial discovery of natural gas may have come as a serendipitous byproduct of the search for brine and salt, and the natural gas fires were certainly used on brine taken from wells to evaporate the water and recover salt. Natural gas wells were called fire wells (火井). By the first century B.C., the technology of well-drilling had advanced, and Chinese engineers were able to dig down over 800 feet, and commonly did so as part of a brine industry in Szechuan. In ancient times, when people found oil underground or seeping up to the surface, they called it Ruoshui (弱水) or Shiqi (石漆) or Shi-ji-shui (石脂水) or Shi-nau-yo (石腦油). During the Song dynasty a scientist named Shen Kua reviewed the various terms used to describe petroleum and gave it the name Shi-yo (stone oil, 石油). In 1090 Shen Kua wrote a book called Dream Pool Essays in which he predicted that fossil fuels such as oil and natural gas would become widely used for energy. Early Chinese uses for oil included weaponry, medicine, lubricants, ink, and lighting. Shen Kua was farsighted in his predictions about the worldwide use of oil. Edwin Drake is often mentioned for digging a modern oil well in Pennsylvania in 1859, starting a boom in the modern petrochemical and mining industries, but people had been drilling oil wells in China for over two thousand years before him.