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| An ancient wheel made of wood (Wikipedia) |
Note: No one knows what genius first invented the wheel, nor even what culture he (or she!) lived in. But it would be hard to fund any culture today that doesn't benefit from this most basic of inventions.
Get Ready: Look around, right where you are. How many examples of wheels can you see (or how many are working away invisibly right near you)?
Some of our most important inventions were created in such a distant past that no one knows their origins.
Fire is the premier example; second only to that is the wheel, commonly used in transportation, where almost everything standard means of travel except the horse benefits from wheels (and they pulled wagons!). Even airplanes have wheels!
"What about ships?" you ask. Well, except for sailboats and a rowboats, any motorized boat, even the enormous vessels that carry passengers and cargo across the oceans, have bowels that are filled with wheels, turning within the engines and driving the propellers--also a form of wheel!
Wheels are all around us. From where I sit, I see a turning fan. But there's also the hard drive of my computer. The electricity that powers my room light (and my computer) comes from turbines of one form or another, perhaps in hydropower dams or the giant mills on "wind farms."
And these are just the large, visible kinds of wheels. There are also tiny cogwheels inside of all kinds of machinery, from the clock on the wall to satellites in space.
The earliest wheels were horizontal, and used for things like making pottery. Wheels seem to have first been used for transportation around 4000 BCE. Before that, if humans wanted to move anything, they either had to lift or drag it. The wheel made it possible to move more and heavier things farther.
But inventing the wheel itself wasn't the most difficult part of the problem. That honor belonged to the axle.
How do you connect a turning wheel to a stationary platform, as in the construction of a wagon? The axle would be a wooden pole affixed to the platform, and the wheel would have to turn around it. The hole in the hub--where wheel and axle met--would have to be tight enough to keep the wheel from falling off, but loose enough to allow the wheel to turn with minimum effort. This "wheel-and-hub" assembly is found today, in one form or another, in virtually all of the wheel examples I mentioned above.
The solving of that problem led to increased crop yields, greater mobility, incalculable numbers of inventions, and, ultimately, the Industrial Revolution.
--------Read more: https://en.wikipedia.org/wiki/Wheel
Practice: Match the term to its definition below:
- affixed
- bowels
- cargo
- cogwheels
- hydropower
- incalculable
- propellers
- stationary
- turbines
- visible
- electricity made by moving water
- not moving
- unable to be counted
- able to be seen
- deep interior parts
- machines turned by steam, water, gas, air, etc.
- goods being carried
- wheels with "teeth"
- fastened; attached
- a bladed turning device for moving airplanes, boats, etc.
Answers are in the first comment below.
Submitted to the Shenzhen Daily for November 2, 2020
Answers to the Practice: 1. i; 2. e; 3. g; 4. h; 5. a; 6. c; 7. j; 8. b; 9. f; 10. d
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