The zipper is a wonderful invention. How did people ever live without zipper? They are very common,so we forget that they are wonderful.They are very strong, but they open and close very easily.They come in many colors and sizes
In the 1890s, people in the United States wore high shoes with a log row of buttons. Clothes often had rows of buttons, too. People wished that clothes were easier to put on and take off.
Whitcomb L.Judson, an engineer from the United States, invented the zipper in 1893. However,his zipper did not stay closed very well.This was embarrassing, and people did not buy many of them.
Then Dr.Gideon Sundback from Swedend Solved this problem. His zipper statyed closed.
A zipper has three parts:1. There are dozens of mental or plastic hooks (called teeth) in two rows.2.these hooks are fastened two strips of cloth.the cloth strips are flexible.They bend easily.3.A fastener slides a log and joins the hooks together. When is slides the order way, it takes the hooks apart.
Dr. Sundback put the hooks on strips of cloth. the cloth holds all the hooks in place.they don't come apart very esily. This solved the problem of the first zippers.
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