China has officially used coal for ironmaking in the Western Han Dynasty, and coal fields in Henan and other places have begun to be mined.

In the Song Dynasty, coal mining has a relatively complete set of technologies. At that time, a circular shaft was drilled from the ground, reaching a depth of forty-six meters, and then the roadway was excavated according to the changes in the underground natural coal seam. The roadway is more than one meter high, and the shape is narrow and wide. The upper width is one meter and the lower width is one meter four. Then the coal fields that need to be mined are cut into several communities, and the “jumping format” is used to gradually withdraw. On the one hand, underground drainage is used to pump water out, and on the other hand, groundwater is introduced into the potholes where coal is mined.

In the Ming Dynasty, the coal mining technology was recorded in more detail. The book said: "Where the coal is experienced for a long time, the color of the soil can be distinguished from the soil surface, and then excavated. Deep to five feet, the square begins to get coal. When the poisonous person is there, the giant bamboo is cut into the middle section, sharp and not inserted into the charcoal. The poisonous smoke is transmitted from the bamboo, and the person picks up the picker from the bottom. It is widened with its left and right sides. Its upper support plate prevents pressure from collapsing. "The method of using a bamboo tube to exhaust gas is very scientific.

In the Qing Dynasty, the book describing coal mining technology was the most detailed and best of Sun Tingjun’s "Yanshan Miscellanies". His record is in line with reality, and it is a summary of the actual experience of coal miners in Zibo, Shandong. He talked about the nature of coal and then talked about the exploration and mining of coal mines in sequence.

Regarding coal mining technology, the book says this:

"Where the charcoal is attacked, there must be a well." This refers to the main well and the shaft. "Although it is deep and unrelenting." Although the shaft is not bent, it is upright. "The charcoal has been obtained, and then the tunnel is going on. As far as its charcoal trip is concerned, the taller ones are double, the thinner and the body are thin and shoulders, thin and sturdy." When the depth of the shaft is equal to the coal seam to be mined, Open the roadway from the side of the shaft, and look at the direction of the coal seam in the direction of the roadway. The coal seams are thick and thin, the roads are high and low, the high ones are two people high, the thin ones are only one person high, and the thin ones are only one person's shoulders high, and the thinnest one is only one person's buttocks high.

"The chisel is smashing, the far is chi. The chisel is sitting, the far is squatting. The chisel is lying, the far one is going." This is the relationship between the chiseling and the coal transporter. When the excavation workers can stand up and work, the roadway is naturally open, so the coal transport workers can walk upright; when the excavation workers can only sit and work, the roadway is low, the coal transport workers have to bend over; when the excavation workers sit on their backs When working, the roadway is extremely low, and the coal workers can only crawl like a donkey.

"The pulse is big and thin, and the snail is smashed. If it is finished, it will be exhausted. It is called the chicken nest. Both of them are well ill." This means that the coal seam is uneven, when it is big, small, and even sharp, this It is not conducive to mining.

"Where the tunnel is, the former hand must be lighted in. The well is night, the light is also the day. The winter gas is hidden, the light is long; the summer is strong, the light is closed. Second, the tunnel must be double, so that the traffic is good, to reach its yang. Attacking the strong and far-reaching, the power is not enough, thinking that the gas well is also said." Here is the underground lighting, underground ventilation. In order to convect the underground air, the workers invented the method of opening the gas well. Gas wells, gas lanes and working wells are separated.

This is the first mention of open gas wells in ancient Chinese coal mining technology, reflecting the new steps in the design and construction of coal mine pits in the late Ming and early Qing dynasties, reaching a new level of technology. Editor / Zhao Jing