Marilyn Brodar, age 9, of Tucson, Arizona, for her question:

Who invented the bicvcle?

An inventor dreams up a brand new idea and then makes a finished model to prove that it works. You would think that somebody dreamed up a marvelous idea and then made a bicycle that looked just like a bicycle. But this did not happen. The first attempt was a wooden tricycle and it had no pedals. Many people added improvements, one by one. And each new model looked more like a real bicycle. Dozens of inventors lent a helping hand before the job was finished.

It took more than 200 hundred years to finish the invention of our marvelous bicycle. Way back in 1655, an inventor named Farfler had the idea that he could walk faster if he pushed himself along on wheels. He made a wooden model with three wheels, a pair of handlebars and a sort of seat. But he did not think of adding pedals. When he straddled the seat, his feet touched the ground. He walked astride., pushing the frame as he went. And the rolling wheels helped him to walk a little faster.

Farfler's weird machine was not very successful and nobody wanted to buy one. But his model was the original ancestor of the bicycle. More than 100 years later, several inventors tried to make better bicycles. Most of their models were not successful. But they were getting closer to the real thing. In the 1880s, Karl von Drais invented a two wheeled bicycle. His model was made of wood. It had no pedals and the rider still had to straddle the seat and push it along as he walked. But Karl von Drais's invention became very popular. However, only rich dandies could afford to buy one     and people called it the hobby  horse.

About 50 years later, Pierre Lallemant was working in the shop of Monsieur Michaux. This was in Paris, France. Pierre added a brand new invention to the bicycle. His model was still made of wood     but it had pedals. But of all things, the pedals were in the center of the front wheel. Later he came to America and sold many of his models. The front wheel pedal bicycle was wobbly and not very fast. But about 100 years ago it was very popular and everybody wanted to ride one.

This inspired many different inventors to add improvements one by one. After the 1850s, new models came along with steel frames and steel wheels with rubber tires, chain transmissions and pedals where they are today. Naturally each inventor was proud of his improved model. But many of them claimed to be the original inventor of the bicycle. The truth is that the bicycle had dozens of inventors    . and each one added an improvement to make it perfect.

It's fun to fly a kite and swing on a swing. But the most fun is riding a bike, pushing the pedals and dinging the bell. What's more, the pushing makes a person's muscles strong and springy and the rider travels without adding any pollution to the air: