Meng Tian was a general in the Qin Dynasty more than 2,200 years ago. He led 300,000 troops to attack the Xiongnu in the north to defend the country. Before the invention of the writing brush, China's words were carved with a knife. Legend has it that Meng Tian led an army stationed in the frontier and needed to report the military situation to Qin Shihuang frequently. Because the situation in the border area changes rapidly, the communication is very frequent and the cutting speed is very slow. In desperation, Meng Tian tore off a pinch of red tassel silk from the soldier's equipment, tied it to a bamboo pole, dipped it in some color, and wrote. He thought it was fast, so he did it and made a lot of writing tools. There are many wolves in the north, and soldiers often fight wolves. After peeling, they made the wolf hair into pens. The grassland outside the Great Wall is crowded with sheep, and wool naturally becomes a tool for making pens. This is the origin of later wolf brush and sheep brush. In this way, it is well-deserved to say that Meng Tian invented the writing brush.