History of chemistry
An important breakthrough in making sense of the list of known chemical elements (as well as in understanding the internal structure of atoms) was Dmitri Mendeleev's development of the first modern periodic table, or the periodic classification of the elements. Mendeleev, a Russian chemist, felt that there was some type of order to the elements and he spent more than thirteen years of his life collecting data and assembling the concept, initially with the idea of resolving some of the disorder in the field for his students. Mendeleev found that, when all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern, or periodicity, of properties within groups of elements. Mendeleev's law allowed him to build up a systematic periodic table of all the 66 elements then known based on atomic mass, which he published in "Principles of Chemistry" in 1869. His first Periodic Table was compiled on the basis of arranging the elements in ascending order of atomic weight and grouping them by similarity of properties.
Russian culture
Nikolai Lobachevsky, a "Copernicus of Geometry", developed the non-Euclidean geometry. Dmitry Mendeleev invented the Periodic table, the main framework of the modern chemistry. Nikolay Benardos introduced the arc welding, further developed by Nikolay Slavyanov, Konstantin Khrenov and other Russian engineers. Gleb Kotelnikov invented the knapsack parachute, while Evgeniy Chertovsky introduced the pressure suit. Pavel Yablochkov and Alexander Lodygin were great pioneers of electrical engineering and inventors of early electric lamps.