Necessity Is the Mother of Invention
Bicycle
Mt. Tambora, a volcano in Indonesia, exploded in 1815.
The explosion created a huge cloud of ash, so crops failed around the world.
As a result, people didn’t have enough food to eat.
Surprisingly, this made traveling difficult.
Why?
In those days, people rode horses, but many horses were killed for food.
People needed a new way to travel, and Karl von Drais invented the first bicycle in Germany in 1817.
Drais’s bicycle had two wooden wheels but no pedals.
How did it move without pedals?
Well, riders simply pushed the bicycle forward with their feet.
The present-day bicycle is the result of many inventors’ work in the 19th century.
Whiteout
Whiteout was invented by Bette Graham.
In 1956, Graham was working at a bank in Texas, USA.
At that time, people had to retype the whole page when they made even a small mistake.
Graham was a bad typist, so she needed a solution.
One day, Graham saw some window painters.
When they made a mistake, they corrected it by simply painting over it.
The next day, she made her own white paint and used it to correct her typing mistakes.
Surprisingly, nobody noticed!
Soon, everybody at the bank began using it.
Webcam
The first webcam was invented to watch a coffee pot.
In 1991, Dr. Quentin Stafford-Fraser and Dr. Paul Jardetzky were working at a computer lab in England.
To work better, they needed lots of coffee.
However, there was only one coffee machine in the building.
So, they had to make many disappointing trips to the empty coffee pot.
As a solution, the two researchers set up a camera in front of the coffee machine.
The camera took pictures of the coffee pot three times a minute.
With special software, all the researchers in the building could see the pictures on their local network.
No more disappointing trips!
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