GALILEO

GALILEO (1564 - 1642)

Galileo said that earth is not the centre of the universe, but like other planets it also revolves round the sun. But when in 1616, he proved for the first time that the sun was the centre of the universe and the earth revolves round the sun. He was summoned before the officials of the church and was ordered to stop his view. He didn’t give any public speech till 1630. Due to pressure he discarded his scientific beliefs. But he said in a broken voice; It is the earth which moves around the Sun. He was imprisoned where he became blind and died. This is the tragic story of Galileo.

Galileo was an Italian astronomer, physician and mathematician. He was born on February 15, 1564 in Pisa. He worked as a lecturer in mathematics in Pisa university. Once he read in a religious book that if two bodies of different weights are allowed to fall simultaneously from the same height the heavy body will hit the ground first. He proved this Aristotle’s statement wrong. To prove his theory he went upto the seventh floor of Pisa tower and dropped two metal balls weighing 100 pounds and 1 pound respectively. Many people were gathered to witness the experiment. The two balls hit the ground at the same time.

Galileo was instrumental earlier in the invention of a pendulum clock. The instrument was then called pulse meter. For this he relied on the principle that beat of the human pulse is fairly regular. It so happened that one day Galileo saw in the church a candelabra hung from the roof by a chain. When it was left it started swinging to and fro. Galileo after keen observation found that the time taken in each wing was the same. The timing he decided was with respect to the beat of the human pulse. His son Vinsenji made a wall clock on this basis later.

Galileo fabricated telescope and explored the universe. He saw the satellites of Jupiter and he proved that milky way is composed of millions of stars.
He published in 1638 his “Discourses and mathematical demonstrations relating to two new sciences”. In this work he disproved the assumption made in the Aristotlean physics. He had developed contacts with kepler. He also published “ A dialogue on the two principle systems of the world” a book in which he has explained the astronomical facts given by Copernicus and has said that Sun is static and is centre of the universe and the earth and other planets revolve round the Sun.

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EVANGELISTA TORRICELLI

EVANGELISTA TORRICELLI ( 1608 - 1647)

WHO MADE THE FIRST BAROMETER IN 1644

Torricelli was born on 15 October, 1608 at Faenza in Italy. He studied science at 16 in Rome. His Professor Benedelti Costelli was a student of Galileo. Torricelli wrote a paper on “Missiles”. Benedelti sent this paper to Galileo who appreciated Torricelli’s thinking power. Torricelli met Galileo three months before his death. He nursed him.

Torricelli invented Barometer which is an instrument used for the measurement of atmospheric pressure. Grand Duke of Tuscamy told once the technicians to lift water to a height of forty feet. Galileo who was the mathematician to the Grand Duke hinted Toricelli to take up the work. He tried using a Pump. But the water did not rise in the pipe more than the height of thirty three feet. The pump was in order. Toricelli knew that a heavier liquid cannot be raised to the same is more than thirteen and half times heavier than water. He felt that the use of mercury would reduce the length of the experimental glass tube to only three feet, as the equivalent height to which mercury might rise would be about 30 inches. Toricelli took a glass tube of about three feet length with its one end closed. He filled it with mercury, closed the open end with his thumb and immersed it in a dish full of mercury there by the open end remained dipped in mercury. As he removed his thumb from the open end from below the mercury level the mercury in the tube came little down and stood at a column length of about 30 inches. Naturally the upper part of the tube became empty. This empty column is known as “Toricelli’s vaccum”. The apparatus used here was the basis for the barometer. Suppose you take the barometer to the peak of a mountain the height of the mercury column falls down. It meant that as we go above the surface of the earth, atmospheric pressure decreases. The mercury barometer is preferable if the highest accuracy of readings is important.

Toricelli’s other inventions are (i) Telescopes (ii) Microscopes (iii) Optical instruments (iv) Fundamental formula for integral calculus. His barometer has become an essential instrument for weather men. He also wrote a commentary on the work of Galileo. He was a professor of Rome University. Toricelli did not live long. He died at an early age of 39. He died on October 25, 1647.

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ALFRED B.NOBEL

ALFRED B.NOBEL (1833 - 1896)

SILVER MEDALLION SHOWING PROFILE OF ALFRED NOBEL

The shortest autobiography ever written is that of Alfred Nobel. It reads as below.

Description: Pitiable half creature, who should have been shifted by the doctor when he made his entry yelling into the world.

Merits: Keeps his nails clean and is never a burden to anybody.

Faults: Lacks family, cheerful nature, healthy stomach, Greatest and only petition, Not to be buried alive.

Alfred Nobel was born in Stockholm in Sweden to Immanuel Nobel, a poor farmer later an engineer. Nobel was schooled at home. Young Nobel was a chemist at 16. He know English, French, German, Russian and Swedish. He worked in US for four years under John Ericsson, the builder of a warship. Then he worked in his father’s factory at Petersburg, Russia and the firm was closed in 1859. The family returned to Sweeden where Nobel began experimenting with explosives. He invented dynamite and earned huge money. Once an accident occurred in his workshop. A nitroglycerine explosion wrecked the plant. His younger brother and four employees were killed. He has to face a huge loss and rebuilding of the factory was a difficult task. There were some restrictions to make nitroglycerine. But after he discovered dynamite his factories at various locations grew well and he made his fortune. He sold dynamite. In 1887 he invented ballistite, a smokeless nitrogylycerine powder. Many countries used it as gun powder.

Noble when he died in 1896 left a substantial amount of nine million dollars, the interest on which, according to his will is awarded every year in the form of Nobel prizes persons for their outstanding works in Physics, Chemistry, Medical Sciences, Literature and peace. Later economics was also added. Albert Einstein, Ravindranath Tagore, Amartyasen, Alexander Fleming and many others are the receipients of Nobel Prize. An element has been named as Nobelium in his memory.

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JOHN DALTON

JOHN DALTON (1766 - 1844)

PROFILE OF ENGLISH MAN

JOHN DALTON ON COIN

Dalton was a British physicist and chemist who gave us the atomic theory which was later called Dalton’s atomic theory.

Dalton was almost self taught. He began his career as a teacher. But his earnings were very heagre. So he worked in farms to enhance his earnings. However in 1793 Dalton became a lecturer in mathematics and natural philosophy at new college in Manchester. With the publication of his atomic theory he became one of the most famous men in Europe. His atomic investigation appeared in a new system of chemical philosophy. He was elected a fellow of the Royal Society in 1822 and 1830. he was one of the eight foreign associates of the French Academy of Sciences.

Dalton earlier essays in science were published in the Centleman’s dairy and the Ladies diary. He was also the author of a series of essays on his meteorological investigations.

Dalton resigned from Manchester college. As a source of earning money he wrote a book on grammar which was interesting and original. He spent rest of his life studying chemical processes.

The basic postulates of the atomic theory are that matter consists of small individual units called atoms. Atoms can neither be created nor he destroyed. All atoms of the same element are identical and different elements have different types of atoms, and that chemical reactions take place by rearrangement of atoms. Using this theory Dalton rationalized the various laws of chemical combination namely law of conservation of mass, law of definite proportions and law of multiple proportions.

Law of multiple proportions or Dalton’s law states that when two elements combine to form more than one compound, the amounts of one of them which combine with a fixed amount of the other exhibit a simple multiple relations.

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JAMES CLARK MAXWELL

JAMES CLARK MAXWELL (1831 - 1879)

Maxwell’s discovery was the electro magnetic theory of light.

Maxwell was born on June 13, 1831 at Edinburgh. Even as a child he was fond of nature. He wished to be always amidst nature. Thus he developed curiosity. At the age of 15, he devised a method to make Cartesian oval. It is just a curvature in geometry. He wrote a paper on his method and this was published by the Royal Society of Edinburgh.

Maxwell was educated at Edinburg university and Trinity college, Cambridge. He became a professor of physics and astronomy at King’s college, London. He was given the Chair of experimental physics at Cambridge. He guided men to build Cavendish Laboratory. At the age of 18 he did research related to the equilibrium between rolling curves and elastic solids.

Maxwell’s electrical theory titled “Treatise on electricity and magnetism” appeared in 1873. “Theory of heat” and “Matter and motion” are his other writings.

Maxwell’s sleeping habits were special. He was sleeping from 5 pm to 9.30 pm., study from 10 p.m. to 2 am, exercise from 2 am to 2.30 am and sleep again unit1l 7 am. It was an uncommon routine. Kelvin, a scientist was his friend. He was showing his experiments to him now and them.

The inspiration for Maxwell’s electromagnetic theory of light was Faraday. Maxwell gave mathematical base for his theory which Faraday could not. He published his paper “Dynamical theory of electromagnetic field” and after eight years he wrote a book. Maxwell worked on kinetic theory of gases. He was the first Cavendish professor of physics at Cambridge in 1871.

Maxwell wrote few poems. His hobby was swimming, gymnastics and horse riding. He had sense of humour. Maxwell proved that time is essential for the movement of electricity and magnetic effects and they travel in the speed of light.
Maxwell calculated the rings surrounding the planet Saturn mathematically and through the gaseous motion. He studied different colour and said that all other colours can be developed from the major three colours red, green and blue. This discovery is made use of to produce colours in colour T.V. Maxwell received Rumford Medal for this discovery. Maxwell died of cancer in November 1879. His mathematical equations enabled to discover radio colour network, existence of X-ray and Gamma rays.

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JOSEPH PRIESTLEY

JOSEPH PRIESTLEY (1733-1854)

Priestly was born on 3rd March 1733 in a village near Leeds in England. His father was a weaver, whose earnings were meager. When he was just seven years, he lost his father and became an orphan. His aunt brought him up. Priestley was trained to become a Bishop Priestley showed keen interest in learning different languages. He leant Arabic, French, Italian, German and Armeic. He was appointed a Bishop of a small Church. His earning was even less than a pound per week. So to increase his own earnings he worked as a teacher and held private tuitions. He wrote a grammar book in the mean time. He was soon taken as a language teacher. He studied chemistry there and did experiments. Few scientists noticed him.

Priestley met Benjamin Franklin and discussed with him. Then he wrote a book on the status of electricity and its history. He was chosen a member of the Royal Society.

Priestley’s house was near a factory that produced wine. Priestley got permission to examine the gas coming out to vessels in which wine was made. He kept a candle in the gas. It blew off. The gas was produced by different methods. It was named fixed air. It was carbon dioxide. The gas was dissoleved in water. Priestley was successful. He named the solution sodawater. For this he was given Gold medal. Priestley became a member of France education institute. He was conducting always experiments and so he was not giving justice to his Bishop job. He was made the Librarian of the Library belonged to Lord Shell Barne, a politician. Priestley went with him to France where he met Antoine Lavoiser.

Priestley was a peaceful man. He participated in French revolution and publicized freedom and equality, brotherhood. He said that churches should be separated from politics. People aroused against him. All his property was destroyed.

Priestley went to Newyork in 1794. There leaders and scientists welcomed him . He joined his sons who were living in pensylvania. He was made Bishop of Unitarian church and professor of chemistry. Priestley continued his experiments in Northambarland. He discovered oxygen. This gas was helping human beings and animals for respiration. Plants were giving out oxygen.

Priestley found ceral, oil and gasoline when burnt in oxygen produced carbon monoxide. It was poisonous gas. He discovered nitrous acid. It was called laughing gas as it was entertaining men.

Priestley died in 1854

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HENRY CAVENDISH

HENRY CAVENDISH (1731 – 1810)

Cavendish was born in the month of October, 1731. His father was Lord Charles, Mother Lady Anne Cavendish. Lord Charles made maximum and minimum thermometers and was the recipient of Kople medal.

Cavendish went to Cambridge at 18 and studied for four years. But he had to study religion. It was a difficult task for him. So he left. Cavendish and his brother fredrich studied mathematics and physics in London and Paris. Both of them elected members of the Royal Society.

Cavendish began his career as an assistant in his father’s laboratory. He was the pioneer to discover the separate existence of nitrogen and synthesise water from hydrogen and oxygen. He attempted to produce nitric acid from a mixture of hydrogen, oxygen and water vapour. He discovered that nitrogen was a constituent of nitric acid. He said that every charged body was surrounded by an electric atmosphere. This helped scientists to formulate the electric field theory. He added iron, zinc and tin separately into sulphuric acid and stored that produced gas in separate balloons. When these were burnt they found burning with light blue flame. He did the same experiment with hydrochloric acid also. The result was same. He weighed them and found the weight being same.

The quantity of gas produced depended on the quantity of metal used. But Cavendish decided wrongly that the gas comes out because of metal and not from acid. Cavendish felt that he had separated phlogiston and he submitted a report to the Royal Society.

The torsion balance that is widely used bears his name. He determined that value of the gravitational constant using it.

Cavendish was always shy. He was rich but he did not marry. He never liked to have contact with others. He used to be alone always. He never spoke to women. To him all men were strangers.

Cavendish died in 1810. he was buried in Durby, England. A cathedral was built in his memory. He had left a lot of wealth which was distributed to establish Cavendish laboratories.

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ALESSANDRO VOLTA

ALESSANDRO VOLTA (1745-1827)

The first electric battery was invented by the Italian Scientist Allessandro Giuseppe Antonio Anastasio count Volta, who built a simple battery which was called a Voltaic Pile in 1800. The Volt a standard measure of electric force, comes from his name.

Volta was born in “Como” a beautiful city in Italy in a poor family. He could study with the help of his relatives who were in high post in the church. Volta was appointed a teacher in a high school after his education. While he was in high school he invented the electrophorus a device to generate static electricity. He was invited to establish physics department in Pavia university. There he had the opportunity to conduct experiments. He studied how Galvani, an Italian anatomist. Pioneered the study of the relationship between living organisms and electricity. Galvani had discovered that a muscle could be made to contract even without subjecting it to electric charge. This he had named animal electricity. Volta didn’t believe it. He made his own experiments and sent a report to the Royal society. This was named Voltaic Pile.

Volta’s battery worked on the principle that, if a plate of copper and a plate of Zinc are placed in a bath of sulphuric acid, an electric current will be created and will flow from the copper to the Zinc. Many scientists conducted experiments using Voltaic cell. The results were (a) Water was divided electrolytically into hydrogen and oxygen (b) Invention of metals sodium and potassium and (c) Experiments on magnets.

Volta received several honours. He was invited to give a lecture at Paris institute. Napoleon, the King presided.

He was selected as senator. The king of Austria nominated him the Director, studies in philosophy, Padua. Volta died in his native como. A statue of him was erected at Como.

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