The first tools-rough hewn stones more than 2 million years old, found at Hadar in Ethiopia- are the earliest evidence of humans. They were round stones dashed against a rock to produce a jagged edge that could be used to cut through tough animal hide or to hack up meat. It took the best part of another million years for early humans to learn to make fire. In doing so, they also won some control of their destiny. Using fire for cooking, heating, light, and defense, they were able to move out of their African birth place. By 300,000 years ago well formed stone tools were being made. Around 10,000 years ago technological discoveries accelerated. Framing developed in many regions, and a more settled way of life gave rise to a stream of inventions including metallurgy, spinning, pottery, and the wheel. Animals began to relieve their human masters of the burden of traction and transport.
By 20,000 BC hunters were finding ways to propel to projectiles more effectively than by simply throwing them. The harnessing of energy began with fire, probably 1.5 million years ago. Water was used for irrigation from around 5500 BC. Only much later in the 1st millennium AD- were the forces of wind and water harnessed.
The first boomerang is made in Europe around 21,000 years ago. By a similar date, the spear thrower is developed to extend the range and power of spears and darts. Known in the Americas as the atlatl, it becomes widespread, used equally in hunting and in warfare. Bows and arrows appear around 16,000 years ago.
In Europe and Asia, asses and cattle are used for traction before 4500BC. First cartwheels are developed in Mesopotamia after 4500BC. They are made of three shaped planks: two semicircles clamped to a solid hub with wood or copper struts. There are considerable advantages: an ox with a cart can transport three times the load it can bear on its back.
Between 4500BC and 4000BC, ploughs come into use in the Middle East and Europe. Wheel making spreads throughout the Middle East and into the steppes. The rims are often reinforced with metal. Horses are domesticated around 4000 BC on the European fringes of the steppe region; as a result people begin to explore the steppes and settle there. From 3000 BC levers are used; they can be seen in Egyptian sculptures. Later, there is evidence in Egypt and Mesopotamia of more sophisticated principles with the shaduff, a bucket on a pole counterbalanced by weights used to raise water from a river.
In the Middle East lighter spoked wheels are developed, followed by swiveling axles, which make four wheeled carts much easier to steer. Spoked wheels make it possible to develop light, manoeurable chariots which become formidable in war, from Africa and Europe to India by 1200BC.
The Archimedean screw, an efficient device for raising water appears in Mesopotamia around 700 BC. At the start of the Christian era, the Romans refine the application of levers with pulleys, about the same time, Vitruvius, a Roman architect and engineer, describes the first devices using natural energy, water and wind.