Windmill is one of very important inventions in the Medieval Ages. Windmill brought the improvement in efficiency of job and the spread of technology to operate some machines at the same time by using cranks and gears. Thw development of "machanical energy"was accelerated hereinafter.
The development of utilizing technology of mechanical energy was accelerated at the speed which mankind had neverexperenced by the invention of steam engine. Steam engine brought people railways,power plant,modern manufacturing plants and so on. But people who worked in plants lost their job,and hte penetration of capitalism brought the discrimination of classes.
The development of shipbuilding technology,telegraphic communication,railway technology,and the invention of airplane in the first half of 19th century made people to communicate worldwide.
3.Well-off life
Invention of electric light bulb is a symbol of modernization in 19th century. Electric light was rapidly spread in the industrial countries around the world with increasing number of power plants, and the age of electric energy had come.