From three to six to over 300, the journey of machines has been a bit more complex than Renaissance scientists could imagine...
Anyone reading E+T today would probably agree that engineering is really very complex, but for Renaissance scientists it all came down to six simple machines – or ‘mechanical powers’ as they were called. These were the lever, the wheel and axle, the pulley, the inclined plane, the wedge and the screw, all quite closely related.
I hardly need to tell engineers what each of these are, but as a quick recap: a lever consists of an arm that is free to turn about a fixed pivot point called the fulcrum. The wheel and axle is a circular (first class) lever whose fulcrum is the axle. A pulley is a grooved wheel that turns freely on an axle, and hence another circular lever. An inclined plane is any stationary slanted surface used to move a load, such as a ramp. A wedge is just a moving inclined plane, like an axe for instance, and a screw is simply an inclined plane wrapped...