In our modern society, we mainly focus on the development of science and technology, but we don't know much about some ancient history and culture, so we mostly understand it through historical events of different dynasties, and then remake a film and television drama. Therefore, in many court dramas, one of the most common phenomena we see is the frequent struggles between courts. Trying to frame others often tries to poison others with food or fruit wine. After this incident is exposed, it is often possible to judge whether they are food poisoning or fruit wine poisoning by reading the silver needle.

Take our modern medicine for example, to judge whether a person has been exposed to toxic substances is mainly to analyze other medicinal components contained in the blood through blood tests, so as to judge whether he is poisoned. In ancient times, it was mainly through the method of making silver needles, but also, the two of them played a very significant role in Sudoku, mainly inserting silver needles into food or fruit wine. If you really turn black?

Among some substances poisoned in ancient times, arsenic is the most common and often heard, so arsenic does not change the color of the silver needle itself, mainly in the process of making arsenic, and there are other magazines in arsenic. Impurities such as sulfide come into contact with silver instruments, which will corrode them. After the chemical reaction between silver needle and sulfide, the surface of silver needle is black, which is also the reason why silver needle turns black after poison test.

But in addition, other kinds of toxic substances may not react with silver needles, so reading materials will not be detected by this method. Therefore, if we simply use silver needle to test the poison, this method has not been adopted yet, but blood is taken for component analysis and detection.