When there is water shortage, it is really not easy to grind noodles. We must promote the development of stone mill together. At first, everyone thought it was fun, but they were willing to help. Later, when they were tired, they left one after another, leaving Bell alone and naturally unable to push.
When Bell got home, he sat in his father's study and thought hard: How can we push the stone mill easily? After a month of research, he came up with a good idea. First, improve the grinding teeth to reduce friction, and then use the round shape of wheat grains to make them close to each other, so that the rotation of grinding teeth is much more flexible.
Bell's main achievements
Bell's main achievement was the invention of the telephone.
In addition, he also made hearing AIDS; Improved the phonograph invented by Edison; He made great contributions to the invention of deaf-mute language; He wrote 100 articles and pamphlets.
188 1 year, in order to find the bullet in American President james garfield, he designed a metal inspection device, which is the predecessor of the X-ray machine. He also founded the British Association for the Promotion of Deaf Education.