John Dalton - English scientist-wagon of the XVIII century

To define only one scientific specialty, to which John Dalton can be attributed, is difficult. One of the most respected and well-deserved scientists of his time was a physicist, chemist, meteorologist. Known for his work on the English language. He was the first to investigate the defect of color vision, which he possessed and who was subsequently named for his name - color blindness.

A self-taught teacher

The universalism of his scientific aspirations and the diversity of his research interests can be partially explained by his lack of systematic education in a particular field. John Dalton was born September 6, 1766 in the town of Eaglesfield, in the county of Kimberland in the north of England, in a poor family weaver. His parents were Quaker dissenters who denied everything connected with the official Anglican church, so it was impossible to attend educational institutions for John.

The need to earn money from an early age, high abilities and the desire for knowledge led to an unexpected result. Thanks to his acquaintance with John Gough, blind philosopher-erudite, who transferred part of his knowledge to him, and persistent self-education, John Dalton began to work as a teacher in a rural school from the age of 12.

Dalton Meteorologist

Dalton's first publication was a work called Meteorological Observations and Experiments (1793). Thanks to her, he met with scientists who helped the young teacher move to Manchester and get the place of a mathematics teacher at New College. Interest in meteorology arose from his acquaintance with Elyh Robinson, a scientist and engineer from his home town of Eaglesfield. John Dalton in his work, containing many ideas that led him to the future discovery of gas laws, developed the theory of the formation of atmospheric flux, proposed by George Hadley.

In 1787, the scientist began to keep a diary of meteorological observations. John Dalton, whose biography is very interesting and instructive, made the last entry in his diary already weakening his hand after 57 years. These records were the result of studying the composition of atmospheric air, the most significant achievements of Dalton in chemistry and physics. One of the first he began to measure the temperature of the air at different heights, making regular trips to the mountains in the Lake District in the north-west of the country.

Color blindness

The second major work of the scientist was devoted to philology - "Peculiarities of English grammar" (published in 1801), but then his attention was attracted by his own visual peculiarity, connected with color perception. After living about 35 years, he discovered that he perceives colors differently than most people, and that his own brother has the same peculiarity. Having quickly understood that it was not only the classification of shades (the color that he called blue, differed from what the others thought of him), Dalton expressed his thoughts on the causes of this phenomenon.

The conclusion about the hereditary nature of such a visual defect was correct, but the explanation for its discoloration of the eye fluid was subsequently refuted. The thoroughness of the research and the originality of the approach to the problem that the scientist displayed in his article "Unusual Cases of Color Perception" (1794), served as the reason for the appearance of the term color blindness, which has since been used by ophthalmologists.

Gas Theory

The ability to draw conclusions from observations and experiments, leading to the related fields of science - the basis of the creative method, which was perfectly mastered by John Dalton. Discoveries in chemistry and physics, made by him, are often based on the same experiments. From the study of the composition of the atmosphere, the flows forming the weather, he proceeded to study the interactions of gases depending on their physical and chemical properties - density, pressure, etc. The results of these studies allowed him to make discoveries in the corpuscular - atomic - nature of matter.

Experiments with gases led Dalton to the discovery of several fundamental laws: the partial (inherent to individual components) gas mixture pressures (1801), the law of thermal expansion of gases (1802) and the laws governing the dissolution of gases in liquids (1803). The conclusion about the difference in the size of the atoms that make up the gases and the presence of a near-atomic thermal envelope allowed Dalton to explain the nature of the expansion of gases upon heating, their diffusion and the dependence of pressure on external conditions.

Atomism of Dalton

The idea that everything in nature consists of the smallest indivisible elements was expressed by ancient authors. But it was Dalton who gave these ideas materiality. The main provisions of his theory were several statements:

• All material objects consist of the smallest - indivisible, only created particles - atoms.
• The atoms of the same substance are the same in mass and size.
• The atoms of different elements differ in size and weight.
• More complex particles of matter consist of a certain number of atoms of different types.
• The mass of complex particles of a substance is equal to the sum of the masses of the constituent atoms.

The model of the molecule, made by Dalton from the wooden balls, is carefully preserved. The most important merit of the scientist is the introduction into scientific practice of the concept of relative atomic weight, the determination of the hydrogen atom as a unit of molecular mass. Atomic mass became the main quantitative characteristic of a substance in chemistry. Not all of Dalton's ideas about the atomic structure of matter were true due to the underdevelopment of general physics, but his theory served as a powerful impetus in the knowledge of the atom.

Confession

Few could achieve in science vertices, having such a complex beginning, as John Dalton. A brief biography of the scientist is a vivid example of how the purposefulness and the thirst for knowledge change the life of a person. It allows us to trace the way of the formation of a strong personality and see how the transformation of a boy without a chance to receive a serious systemic education happened, to whom the parental convictions closed the way to the university, to the world-renowned scientist, a member of the most prestigious scientific Academies of Europe.

There is little in the history of examples of such a devoted, almost monastic service to science that John Dalton led. Photo portraits written from the scientist in the final period of life, show a man who gave all the power to methodical and hard work.

The reward for Dalton was the recognition of colleagues and students. The statue of the scientist was installed at the entrance to the Royal College of Manchester, where he taught during his lifetime. In the future, this recognition grew into true world fame.