1564, a black mineral-graphite was discovered in a place called barodale, England. Soon, some local shepherds found that they could mark their sheep with graphite. Inspired by this, people cut graphite blocks into small strips for writing and painting. But graphite strips are easy to get dirty and break. 176 1 year, German chemist Faber solved this problem: he first ground graphite ore into powder, washed it with water to remove impurities, and got pure graphite powder; Then he mixed sulfur, antimony, rosin and other substances into graphite powder; Then this mixture is heated and solidified and pressed into the shape of a pen, which is the earliest prototype of a pencil.
The second stage, the birth of wooden pen container: after a hundred years of development, the "pencil" at this time entered the primary stage of its own evolution, and a wooden pencil rod appeared, which became a semi-finished product of the "pencil", mainly used in the market, and users needed to cut it again before using it;
From today's perspective, the "pencil" invented by Comte is actually just pencil lead. The task of putting a wooden coat on pencil lead was completed by an American carpenter named William Monroe in 18 12. The machine invented by Monroe can cut standardized battens with a length of 5 to 18 cm, and dig a groove just suitable for pencil lead in the middle of the battens. Pencil lead was put into the groove, and then two pieces of wood were closely bonded to make the first pencil rod in the modern sense. Until today, this is still the standard process of making ordinary pens.
The third stage,
The birth of a pencil with a cap [2]; A pencil with a cap is added to the original traditional pen holder, which overcomes many shortcomings of the traditional pen holder, such as poor safety, unsanitary, easy to roll and fold, and easy to carry, so it is called a "pencil" in the true sense. 20 12, Mr Luan Liyu, a native of China, invented the world's first "open" pencil with a cap.
For others, see /view/2778.htm? Fr = Aladdin #5