Animal Farm: Chapter 5
WINDMILLS
The most basic definition of a windmill is a machine that through the power of the wind creates other forms of energy. It does this by rotating blades or sails, and it can even create such forms of energy as electricity for example.
The first wind powering machine was build as early as the first century. There are two types of windmills; vertical axle windmills and horizontal axle windmills. The first vertical axle windmill was first seen in the ninth century in Persia, but as for the horizontal windmill it wasn’t seen till the end of the twelfth century. The horizontal windmill was used mainly for grinding grains.
In 1745, in England, Edmund Lee invented the fantail, which is a smaller windmill that is mounted at right angles to the main sails which will automatically turn the heavy cap and main sails into the wind. There are many more types of windmills, such as the smock mill; an older variation of the tower mill, grinding mills; for grinding grains, and sawmills; which pumps water for land drainage or water supply.
In 1772, Andrew Meikle, a Scottish millwright developed the spring sail. It was made from a series of connected parallel shutters, which depending on the speed and power of the wind, opened and closed. In 1789, it was Stephen Hooper that invented the roller reefing sail; it allowed adjustments of the sail while still in motion. In 1807, it was the Norfolk engineer William Cubitt that invented the patent sail; in which there was a chain and rod that passed through the centre of the windshaft. These new and improved sails no longer required constant supervision unlike the previous, they combined the inventions of Meikle and Hooper; it had the shutters of the spring sails and the automatic adjustment of the roller reefing sails.
Over the years, the industrial revolution and the importance of windmills have changed. Primary industrial energy sources have been replaced by steam and internal combustion engines, polder mills were replaced by steam and diesel engines. Some historic mills have been preserved for their historic value.
Modern mills are most commonly referred to as wind turbines or wind generators today. They are mostly used to generate electricity. The largest today, generates up to 6WM of power. It is a renewable energy source, and is becoming more popular, since fossil fuel consumption is becoming an increasingly more of an environmental concern.
