The Zipper
The zipper is a wonderful invention. How did people ever live without zippers? 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 long row of buttons. Clothes often had rows of buttons, too. People wished that clothes easier to put on and take off. were
Whitcomb L. Judson, an engineer from the United States, invented the zipper in 1893. However, his zippers didn't stay closed very well. This was embarrassing, and people didn't buy many of them. Then Dr. Gideon Sundback from Sweden solved this problem. His zipper stayed closed.
A zipper has three parts:
1. There are dozens of metal or plastic hooks (called teeth) in two rows.
2. These hooks are fastened to two strips of cloth. The cloth strips are flexible. They bend easily.
3. A fastener slides along and joins the hooks together. When it slides the other 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 easily. This solved the problem of the first zippers.
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