It turns out that when the ancients made mistakes in writing, they would smear the wrong words with orpiment, which is a mineral and can be used as a pigment. The rigorous Shen Kuo survey compares several methods of word correction: scraping with a knife is easy to damage the paper; Sticking typos on paper is easy to fall off; It is not easy to cover typos with lead powder. Only with orpiment, typos can be easily erased and will not be removed for a long time. The idiom "loose lips" also means that a person has no factual basis and speaks casually. Anyway, what he said was wrong, and he smeared it like a loose tongue and changed his words to deny it.
Modern weeding uses pesticides, except grass, but a pile of pesticide residues also pollutes plants that want to be preserved, which makes people unhappy when they eat vegetables and fruits, and they are always worried about chemical pollution of one kind or another. In terms of healthy eating, the ancients were far luckier than us. Crops in the field are picked, washed and eaten. Pick the fruit from the tree, wipe it and eat it. The method of weeding by the ancients was natural and environmentally friendly: "Yang Wengong's" Talking about the Garden "recorded that the queen of Jiangnan grew grass in front of the pavilion in summer, and Xu Kai ordered the grass to be buried in the cracks with cinnamon dander. "Lu's Spring and Autumn Annals" says that there is no miscellaneous wood under Guizhi. Gai Guizhi is spicy and stinging, so it is also. But it is natural for Gui to kill vegetation, not for Xin Zhi. " "On Lei Gong Cans" said: "Take laurel as the tripod, nail it to the wood, and the wood will die. "A tiny pot may not sting a tree, but it is self-defeating."
It turns out that the ancients used osmanthus twigs to weed. This "osmanthus" is not a osmanthus tree, but cinnamon, which is still used as a cooking spice in modern times. It is said that the Queen of Southern Tang Dynasty scattered cinnamon crumbs into the cracks of bricks on the ground according to the method of family education, and all the weeds died all the year round. Weeding with cinnamon chips is so immediate. This method was recorded as early as Lu's Spring and Autumn Annals, which shows that the practice of the ancients produced true knowledge.