Who Discovered the Circulation of the Blood?

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William Harvey (1578-1657), an English physician, was the first to accurately describe the circulation of blood. He spent much of his time doing research on heart and blood vessels. Harvey showed that blood flowed through the heart, veins and arteries in one direction only and one way valves in the heart and veins prevented it from flowing in the opposite direction. During Harvey's time, there was no microscope. His theory relied on the fact that there had to be a connection between the veins and arteries. He said that, as both veins and arteries are divided into smaller and smaller branches, the connecting vessels must be too small for the eye to see. Later, with the aid of microscope, Harvey was proved right. discovered that nitro-glycerine could be handled safely when it was soaked into a powdery rock. He named it dynamite. Later, Nobel developed more powerful explosives and became very wealthy. He left his money to pay for a series of international awards, to be given to people making a mark in their field. These awards are given every year and are known as Nobel Prize.

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