1. PowerPoint 17.3

2. In 1817, Baron von Drais invented a walking machine. It helped him get around his big garden faster.

3. When the Baron pushed his feet against the ground, the machine would roll forward. It was made of wood.

4. In 1865, a pedal was invented for this two- wheeled riding machine. This machine was called “fast foot”. It was also made of wood.

5. In 1870, the first all metal machine appeared. People could take a ride for a longer time.

6. In the 1880’s, the front wheels of the bicycle became larger and larger. People discovered that the larger the wheel, the farther they could travel with one rotation of the pedals.

7. In 1884, Thomas Stevens took two years to travel around the world on a bicycle. He was the first person to pedal around the world.

8. People wanted to buy a wheel as large as their leg length would allow.

9. Later, people found that the large wheels caused a lot of danger because if the front wheel was stopped by a stone or people suddenly fell off the bicycle, they might hurt their head or break their neck.

10. Some people didn’t want to risk their necks. Ladies also felt that their long skirts and corsets caused them trouble when they sat on the high wheels.

11. An adult tricycle was invented for ladies. This tricycle was also welcome by some gentlemen such as doctors and lawyers.

12. Nowadays, people had made lots of improvements to the design. Source: http://www.jimlangley.net/spin/schwinnauction.htmhttp://www.jimlangley.net/spin/schwinnauction.htm lhttp://glorifiedplumber.com/gp/bicycle.htm Pedalinghistory.com http://hk.search.yahoo.com/search/images?p=bicycle&b=157&ei=BIG5

13. The End