THE ROOT OF IT ALL The word wheel comes from the root word wegh which means to convey particularly by a wheeled vehicle in the ancient language from which it is believed all Indo-European languages derived 3 In Old English the word became hweol Because the root word for wheel can be found in almost every offshoot of the original Proto-Indo-European language this means wheels and wheeled vehicles were around when the language was last used approximately 6,000 years ago transportation cars trucks trains planes motorcycles wagons farm equipment skateboards and of course bicycles would not function without them But wheels are not only used for transportation Practically every machine uses a spinning disc of some sort Wheels can be found in everything from computer disc drives to clocks electric toothbrushes and dishwashers Although wheels are widely used now they were invented relatively late in human history People were already forming societies herding domesticated animals and farming during the Bronze Age when the wheel first appeared The first wheels were not even used for transportation Archaeological evidence indicates the very first wheels may have been attached to children’s toys Probably the earliest functional use of the wheel was for making pottery The timesaving product-improving pottery wheel would serve as inspiration for countless wheeled machines that came after it Some ancient civilizations such as the North American Indians Mexican Aztecs and Peruvian Incas reached high levels of civilization without the wheel 10
From the Human Mind Many human inventions are inspired by nature The hook-and-loop fastener used on everything from sneakers to spacesuits was created after Swiss inventor Georges de Mestral noticed how plant burrs attached to his dog’s fur during walks in the woods Certainly the airplane was inspired by people’s observation of birds in flight In the case of wheels however there were no known examples of wheels in nature at the time they first came into use Wheels were truly an invention that sprang from the human mind WHEELED BACTERIA Some single-celled bacteria have an interesting way of getting around a flagellum An organic rotating engine drives the long whiplike flagellum The engine powered by protein is anchored to the cell wall and drives the flagellum rotating it at up to 100 times per second The flagellum allows the bacteria cell to move and change direction So in whose mind was the wheel conceived Unlike Thomas Edison’s light bulb or Gottlieb Daimler’s gas-powered automobile the name of the wheel’s inventor or possibly many inventors in different parts of the world is not known Although the skills needed to build wheels existed in both Europe and the Near East the first evidence of a wheeled vehicle is a pictograph of a wheeled sled made in approximately 3500 BCE in Mesopotamia part of modern-day Iraq Pottery remnants from this era found in southern Poland also contain representations of a 11
four-wheeled wagon Wherever the first wheels were made the technology spread rapidly between 3400 and 3000 BCE On a Roll Other than minor improvements such as spokes sectioned rims and metal tires vehicle wheels remained relatively unchanged for thousands of years until the Industrial Revolution and the invention of the pneumatic tire in the 1800s But machines that used wheels or wheel-like devices such as gears and moving discs were on a roll from the very beginning If there was a way the wheel could make a task easier and improve life there was an inventor ready to take advantage of it Wheeled vehicles and machines make tasks easier and they have improved everyday life in many ways It is not an exaggeration to say the wheel changed the world Wheeled grain mills produced more and more food Better and more abundant pottery increased storage capacity for that food Wheeled carts capitalizing on the strength of domesticated animals such as horses and oxen carried heavier and greater quantities of food and goods longer distances in shorter periods Spinning wheels spun thread to clothe the ever-increasing population eating the bread made from all that grain In time the laborsaving benefits of the wheel freed people from having to devote all their 12
LEVER WHEEL AND AXLE PULLEY INCLINED PLANE WEDGE SCREW These six machines comprise the building blocks with which all complex machines are made They serve a useful purpose by changing the strength or direction of a force energy to survival enabling them to pursue education arts and other creative endeavors Improvements brought by the wheel made it possible for civilization to expand in countless ways SIX BASIC MACHINES The wheel is one of six basic machines the lever wheel with axle pulley inclined plane wedge and screw All simple machines create more force than is put into them by transferring or amplifying the initial force Force applied to a wheel for example wind moving a windmill’s blades magnifies the rotation of the axle Force applied to an axle such as from a car’s gasoline engine magnifies the rotation of the wheel Simple machines have been used for thousands of years in various forms The term mechanical advantage indicates the ratio of the output force to the input force For example looping a rope over a barn rafter and pulling on it to lift a heavy object creates a favorable mechanical advantage compared with lifting the object unaided 13
