Joseph John Thomson (1856-1940), British physicist, Nobel laureate. was born near Manchester, Lancashire, and educated at Owens College (now part of the University of Manchester) and Trinity College, University of Cambridge. In this institution taught mathematics and physics, he was professor of experimental physics at the Cavendish Laboratory, and Rector of Trinity College (1918-1940). He was also president of the Royal Society (1915-1920) and professor of natural philosophy of the royal institution of Great Britain (1905-1918).
Thomson received in 1906 Nobel Prize in physics for his work on the conduction of electricity through gases. He is considered the discoverer of the electron by his experiments with the flow of particles (electrons) that make up the cathode rays. Theoretical and an experimenter, Thomson developed in 1898, the plum pudding theory of atomic structure, which held that the electrons was n as 'plum' negative embedded in a 'pudding' of positive matter. In 1908 he was knighted.
John Dalton (1766-1844), British chemist and physicist who developed the atomic theory which is based modern physical science. Born September 6, 1766, in Eaglesfield, Cumberland (now Cumbria). was educated at a Quaker school in his hometown, where he began teaching at the age of 12 years. In 1781 he moved Kendal, where he directed a school with his cousin and his older brother. He went to Manchester in 1793 where he spent the rest of his life as a teacher, first at New College and later as a private tutor.
In 1787 Dalton began a series of meteorological studies that continued for 57 years, accumulating over 200,000 observations and climate actions in the Manchester area. Dalton's interest in meteorology led him to study a large number of phenomena and the tools needed to measure them. It was the first to test the theory that rain is caused by a decrease in temperature, not by a change in atmospheric pressure.
However, the first work of Dalton, meteorological observations and essays (1793), he paid little attention. In 1794 appeared in the Literary and Philosophical Society of Manchester an essay on blindness, a failure that he suffered, the trial was the first description of this phenomenon, named Dalton himself.
His most important contribution to science was his theory that matter consists of atoms of different masses that are combined in simple ratios to form compounds. This theory, which Dalton first formulated in 1803, is the cornerstone of modern physical science ( see Chemistry, Physics). In 1808 he published His work philosophy New chemical system, including atomic masses of various known in relation to the mass of hydrogen. Their bodies were not completely accurate but they are the basis of the modern periodic table of elements. Dalton arrived at his atomic theory through the study of the physical properties of atmospheric air and other gases. In the course of the study found the law known as 'Dalton's law of partial pressures', whereby the pressure exerted by a mixture of gases equals the sum of the partial pressures exerted every gas if volume occupied by himself total mixture.
Dalton was elected to the Royal Society of London in 1822 and four years later was awarded the gold medal of the society. In 1830 Dalton became one of the eight foreign members of the French Academy of Sciences. died on July 27, 1844 in Manchester.
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