Frederick Gardner Cottrell (1877-1948)

Frederick Gardner Cottrell was an American chemist, in 1906 invented the electrostatic precipitator, and electrical device for removing suspended impurities such as dust, fumes or mist from air and other gases. It has proved to be of immense use in removing pollution-causing substances from the exhausts of factories and power plants. It works by charging the polluting molecules and then separating them by depositing them on oppositely charged electrodes as opposite charges attract each other.

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Edmund Halley (1656-1742)

Edmund Halley, an English astronomer did a lot of research on comets. He observed a comet in 1682, and showed that it was the same comet which had been seen earlier in 1531 and 1607. He predicted that it would again be seen in 1759, 1835, 1910 and 1986. This comet is known as Halley's Comet. Some of you may be able to spot it when it reappears in 2062!

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Count Alessandro Volta (1745-1827)

Count Alessandro Volta, an Italian physicist is known for his pioneering work in electricity. He made the first electric battery, called the voltaic pile. Among his many other contributions to science was the invention of the device known as the electrophorus which produced static charges. Napolean made Volta a Count in honour of his work. Volt, the unit of electric voltage, is named after him.

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Charles Augustin Coulomb (1736-1806)

The unit for measuring amount of charge is called 'coulomb' and is named after this French physicist. Coulomb made sensitive instruments to measure the forces between electric charges. He also worked on friction and magnetism.

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Ernst Mach (1838-1916)

Ernst Mach, Austrian physicist showed that when an object crosses the speed of sound, there is a loud sound called a sonic boom. Today we know that loud sonic booms are produced when a supersonic jet crosses the speed of sound. To honour the scientist the speed of supersonic aircraft is today given in terms of Mach numbers. These numbers relate the speed to the speed of sound. Thus, an aircraft travelling at Mach 2 has a speed double that of sound.

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Sir Isaac Newton (1642-1727)

Isaac Newton was one of the greatest scientists who ever lived. He was a mathematician and physicist. Many theories of modern science are based on the laws that he discovered.
Newton was born in Woolsthorpe in England. In 1669, at the age of 27 he became professor of Mathematics. In 1686 he published his famous book 'The Mathematical Principles of Natural Philosophy' in which he presented his theory of gravitation and the laws of motion. His theory of gravitation says that all matter pulls all other matter towards itself. Newton studied moving objects and gave the famous laws of motion.
Newton studied light and realized that 'white light' (for example sunlight) is a mixture of light of different colours. When sunlight falls on water droplets in the air, it splits into separate colours. This is how a rainbow is formed.
Newton invented the mirror telescope, which overcame some defects of telescopes in use at that time. Many of our present-day telescopes are based on his design.
Newton, along with another mathematician Leibniz, is considered to be the father of a very important branch of mathematics called calculus. One of Newton's greatest qualities as a human being was that he was very modest about his achievements.

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Valerie Jane Morris Goodall (1934 - )

Valerie Jane Morris Goodall is an English primatologist, who works for protection of wildlife, especially the primates of Africa, and their habitats. Although she was interested in animals from her youth, it was her association with anthropologist Louis Leakey that prompted her to the study of the chimpanzees in 1960. She is best known for her 40-year-long study of chimpanzees in the Gombe Stream National Park in Tanzania. In 1977, she founded the Jane Goodall Institute to support the conservation efforts at the Gombe Park.

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Eugenio Barsanti and Felice Matteucci

Eugenio Barsanti and Felice Matteucci are the Italian inventors of the internal combustion engine in 1853, which changed the face of industry and transport in the world. They first realised the potential of the expansion of combusting gases within a motor and worked on it to produce the Barsanti-Matteucci engine. The engine used the return force of the piston due to the cooling of the gas. They also developed a two-cylinder 5 HP motor in 1856.

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Hermann Studinger (1881-1965)

In 1920, Hermann Studinger, a German chemist proposed for the first time that plastics were made of giant long chain molecules. This lead to a sudden burst of scientific investigations on plastics. As a consequence, a large number of new plastics were intoduced in the 1920s and 1930s. This included PVC. Staudinger won the Nobel Prize in 1953 for his contribution to the development of plastics.

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Benjamin Peary Pal (1906-1989)

Benjamin Peary Pal was an Indian agricultural scientist worked on the development of disease-resistant varieties of wheat. He was the first Director of the Indian Council of Agricultural Research at New Delhi.

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