Weights and measures are the standard of measurement units used in ancient China.

Traditionally, weights and measures are the general name of standards for measuring length, volume and weight. Degree-the instrument used to measure the length is called degree, quantity-the instrument used to measure the calculated volume is called quantity, and the instrument used to measure the weight of an object is called scale.

Weights and measures refer to items used to measure the length, volume and weight of objects in daily life. The development of weights and measures began at the end of primitive society. Due to different regions and national conditions, the methods of measurement and statistics are also different.

For a long time, baht, taels, gold, jun and stone have been used as units of weight. However, in ancient times, there were different opinions about the unit of weight. For example, Sun Tzu's Mathematical Classics says: "Start with millet, ten millet is one (the ancient word" tired "), ten millet is one baht, and twenty-four baht is one or two." "Master yuan? Discrimination: "Ten millet weighs one kyu, and ten kyu weighs one baht. "Shuo Wen Jin Wen Bu": "Yi, six baht. "Huai Nan Zi Yan Quan" has a high lure note: "Six words are both said. "Jade and Gold Department;" Hey, number 22. "

Ji Yun Zhiyun: "Twenty-four beams are enough." Wait a minute. "Millet", "Millet", "Miao" and "Gui" are all borrowed from the names of Millet and Guibi, but they are no longer used. "Zi", "Yi", "Zhong" and "Yun" are all borrowed names of coins, and they are no longer used. Therefore, there are various opinions. The names of the five units, namely, Baht, Liang, Jin, Jun and Shi, were relatively consistent until the Tang Dynasty.

Its carrying method is worth mentioning: 24 baht is two, 16 is two Jin, 30 Jin is jun, and 4 Jun is stone. Regarding the use of small units such as less than half, cents, cents, silk, and sudden, Liang Tao Hongjing of the Southern Dynasty once said: "The name of the agent is different from today, and there was no distinction in ancient times. Today, ten millet is one baht, six baht is one point, and four are divided into one or two. " Don? Su Jing pointed out: "6 baht is 1 minute, which is 2.5 dollars."

It can be seen that since the Tang Dynasty, "money" originally used as money has been regarded as a unit of weight, and "ten money is one or two", but the fractional carry at that time has not yet been determined as one tenth of money. In addition, there are points, Li, Mao, Si and Hu. It was originally a decimal name, and later borrowed length as the name of the weight unit. Since the Song Dynasty, they have been designated as decimal units of money.

In the Song Dynasty, the names of baht, grain and millet were abandoned, and the names of their weight units were stone, jun, Jin, Liang, Qian, fen, Li, milli, silk and sudden in descending order, and their carrying methods were as mentioned above. Song system weights and measures have been used until Yuan, Ming and Qing dynasties, and rarely changed. However, it must be pointed out that in the medical prescriptions of the Song, Yuan, Ming and Qing Dynasties, everything that said "fen" was "fen", while in the Jin and Tang Dynasties, a fen was two and a half dollars, which was different.