求一个关于化学发展史的英语演讲

Ever since human beings, the chemical will be formed a deep bond with humans. Fire by rubbing sticks, cook food with fire, firing pottery, smelting bronze and iron, are chemical technology. It is these applications, greatly promoted the development of social productive forces at that time become a symbol of human progress.
Today, the chemical as a basis for discipline, in the science and technology and all aspects of social life, are playing an increasing role. From ancient times, along with the progress of human society, chemical, historical development experience of what times?

Period of ancient chemical processes. At this time the human pottery, metallurgy, brewing, dyeing and other processes, mainly in the practical experience under the direct inspiration came after the number of years to explore, chemical knowledge has not been formed. This is a chemistry infancy.

Period of alchemy and pharmaceutical chemistry. From 1500 BC to AD 1650, alchemy warl