Han1= 20ml; 1 l = 200ml 1 barrel = 2000ml1= 2000ml;
Han 1 foot = 230mm；; 1 inch = 23mm
Before the Tang Dynasty, the measurement of traditional Chinese medicine basically retained the Han system and did not change with the change of official system. (Only from the Jin Dynasty, a "point" was added between the Chinese-made Thai baht and the two, that is, 6 baht was 1 and 4 was 1. ) This is explained in the Six Classics of Tang Dynasty and Tang Yao Hui. For example, there are three scales in the Tang Dynasty: large scale system, large scale system for public and private use, and large scale system for internal and external lawsuits. The small scale is the same as the Chinese scale, which is limited to the application of "mixing soup and medicine" and "adjusting clock method" Measurement and capacity are also binary, 1 large scale (Tang scale) = 1.2 small scale (Han scale); 1 Big Dou (Tang Dou) = 3 Small Dou (Han Dou). Jin Shu Fa Ji Shi Lu pointed out that the meaning of medicine scale should not be changed casually: "The doctor is anxious for life, and the scale is different from ancient times, especially harmful." This is why the China system was preserved before the Tang Dynasty.
In the Song Dynasty, 1 was converted into 10, and the units of measurement such as money, minutes, minutes and cents were all based on 10. The product is still 16, which means 1 kg. After the Song Dynasty, this new system was adopted in prescription books and measurement of traditional Chinese medicine, which was consistent with the official scale. From Song Dynasty to Qing Dynasty, the weight of Kuping system changed little, about 600 grams per catty. It was used until the establishment of People's Republic of China (PRC), commonly known as the "old scale". After 1949, in order to further unify the national weights and measures system and facilitate the conversion with metric system, 1 kg was set at 500g.
Drugs measured by weight in the prescription can be directly converted into modern measurement (such as 1 = 15g), and drugs measured by volume and scale can be converted into modern volume and scale before weighing. For example, japonica rice 1 liter, now 200 ml of japonica rice is about 180 g; Pinellia ternata is half a liter, and now it is about 50 ~ 60 grams with Pinellia ternata 100 ml; Half a liter of Schisandra chinensis is about 30 grams; Magnolia officinalis 1 ft. According to Yao Xin Fang and Sketch Fang, it should be "3 points thick and 1.5 inch wide". Today, Magnolia officinalis with a medium thickness, 3.5 cm wide and 23 cm long weighs about 15 g.. Drugs measured by quantity can directly use the original quantity (such as jujube and ebony), and those that need to be weighed can be re-weighed according to the original quantity. If someone says that almond 100 pieces = 40g, peach kernel 100 pieces = 30g, immature bitter orange 1 piece = 18g, aconite 1 piece = 5g, aconite = 30g, wild aconite 1.