Eraser trivia: What did you use before without an eraser?

When we were students, it can be said that we used many kinds of stationery, all kinds. We have used pencils, erasers, rulers, pens, correction fluids, paste papers, etc. that have appeared until now. And you know that there is a very mysterious story behind these stationery.

Take the eraser we often use. Eraser is not naturally there. Rubber has a history of more than two hundred years. Before this, people did not have an eraser to use. They used bread to erase pencil characters, but the pencil characters of the bread eraser were blurred and dirty, and the effect was very bad.

In 1770, British scientist Priest first discovered the rubber. In fact, the rubber at that time was the rubber produced by Indians. It was a kind of liquid from the rubber tree. After being oxidized, it solidified into an elastic colloid. By chance, it was used to erase pencil writing and found that it could erase pencil writing. So people began to use this natural rubber to erase pencils. But this natural rubber is easy to rot and deteriorate. In 1839, scientists discovered that sulfur can make the texture of rubber more reliable and not easy to decay. Some plastic, vegetable oil, and crushed stone were also added. After adding these substances, the eraser effect of the eraser becomes very good and very clean.

In 1858, an American inlaid an eraser on the end of a pencil and obtained a patent. This kind of pencil has quickly become popular all over the world, and students in almost every country are using it. Everyone, look at a small eraser, there is a magical story behind it.