Theme 11. Science in the period of industrial revolution.

The inventors of the machines that produced the industrial revolution were not scientists, they were self-taught masters. Some of them were illiterate; for example, Stephenson learned to read at age 18. During the industrial revolution, science and technology developed independently of each other. In particular, this concerned mathematics, vector analysis appeared at this time, the French mathematician O. Cauchy created the theory of functions of a complex variable, and the Englishman W. Hamilton and the German G. Grasman created vector algebra. In the works of Laplace, Legendre and Poisson, probability theory was developed. The main achievements of physics were associated with the study of electricity and magnetism. At the turn of the XVIII-XX centuries, the Italian physicist Volta created a galvanic battery; Such batteries for a long time were the only source of electric current and a necessary element of all experiments. In 1820, the Danish physicist G. Oersted discovered that an electric current acts on a magnetic needle, then Frenchman A. Ampère discovered that a magnetic field appears around the conductor and between two conductors there are forces of attraction or repulsion. In 1831, Michael Faraday discovered the phenomenon of electromagnetic induction. This phenomenon consists in the fact that if a closed conductor intersects magnetic lines of force as it moves, an electric current is excited in it. In 1833, German scientist Emil Lents, who worked in Russia, created a general theory of electromagnetic induction. In 1841, Joule investigated the effect of heat during the passage of electric current. In 1865, the outstanding English scientist James Maxwell created the theory of the electromagnetic field.

The theory of electromagnetism was the first area where scientific developments began to be introduced directly into technology. In 1832, the Russian citizen Baron P.V. Schilling demonstrated the first sample of the electric telegraph. In a Schilling device, electric current pulses caused a deflection of an arrow corresponding to a specific letter. In 1837, American Morse created an improved telegraph, in which transmitted messages were marked on a paper tape using a special alphabet. However, it took six years before the American government appreciated this invention and allocated money to build the first telegraph line between Washington and Baltimore. After that, the telegraph began to develop rapidly, in 1850, a telegraph cable connected London and Paris, and in 1858 a cable was laid across the Atlantic Ocean.

At the end of the XVIII century was born a new science, chemistry. Before alchemists believed that all substances consist of the four elements of fire, air, water and earth. In 1789, Antoine Lavoisier experimentally proved the law of conservation of matter. Then John Dalton proposed an atomistic theory of the structure of matter; He argued that atoms of different substances have different weights and that chemical compounds are formed by a combination of atoms in certain numerical ratios. In 1809, the law of multiples was discovered in the chemical interaction of gases. This phenomenon was explained by Dalton and Gay-Lussac as evidence that equal amounts of gas contain the same number of molecules. Later Avogadro hypothesized that in a certain volume (say, a cubic meter) of any gas contains the same number of molecules; This hypothesis was experimentally confirmed in the 40s by the French chemist C. Gerard. In 1852, the English chemist E. Frankland introduced the concept of valence, that is, the numerical expression of the properties of atoms of various elements to join chemical compounds with each other. In 1869, DI Mendeleev created the periodic table of elements.

In the first half of the 19th century, the chemical industry produced mainly sulfuric acid, soda and chlorine. In 1785, Claude Berthollet proposed bleaching with bleach. In 1842, the Russian chemist Nikolai Zinin synthesized the first artificial dye, aniline. In the 1950s, the German chemist A. Hoffmann and his pupil W. Perkin obtained two other aniline dyes, rosanelins and movine. As a result of these works, it became possible to create an aniline dye industry, which received rapid development in Germany. Another important branch of the chemical industry was the production of explosives. In 1845 Swiss Schenbein invented pyroxylin, and Italian Sabrero - nitroglycerin. In 1862, the Swede Alfred Nobel established industrial production of nitroglycerin, and then moved to the production of dynamite.

In the 1840s, the German chemist Justus Liebig substantiated the principles of the use of mineral fertilizers in agriculture. Since that time, production of superphosphate and potassium fertilizers began, Germany became the center of the European chemical industry.

One of the achievements of experimental chemistry was the creation of photographs. In the 18th century, an attraction was used with a camera obscura. It was a box with a small hole in which a magnifying glass was inserted; on the opposite wall one could see an image of objects in front of the camera. In the 1820s, the French artist Joseph Niepce attempted to capture this image. Having covered the copper plate with a layer of rock pitch, he inserted it into the chamber; then the plate was exposed to various chemicals to produce an image. The whole thing was in the selection of the photonic layer, the developer and the fixer. It took many years of experiments, which after the death of Niepce continued his assistant Louis Daguerre. By 1839, Daguerre succeeded in obtaining an image on plates coated with iodide silver after their manifestation in mercury vapor; thus appeared daguerreotype. The French government appreciated this invention and appointed Daguer a life pension of 6,000 francs.