Euler Christopher Leonard General data:
20.04.1743 - 20.02.1808
Place of birth: Berlin City, federal state of Brandenburg, Kingdom of Prussia
Key interests: astronomy, geodesy, meteorology
Biography:
He was born on April 20 (according to the Julian calendar or May 1 according to the Gregorian calendar) in 1743 in the Berlin city of Brandenburg federal land of Kingdom of Prussia, in a large family of a mathematician, physicist and mechanic. He had a noble origin. In Berlin, he received the education of an artilleryman. He was well versed in astronomy and geodesy and until 1767 served as a lieutenant in the Prussian royal artillery (during the Seven Years' War he served as an officer in the Prussian artillery, and after his father's move to Russia, at the latter's request, he asked to be released from service, for which, however, Frederick the Great did not agree and, after Euler's repeated request, had him arrested as a native of Prussia and imprisoned in a fortress. When this became known to the Empress Catherine II, she interceded for Euler and wrote a letter to the king, who on January 17, 1767 ordered his release Euler and immediately sent him with a letter in response to the empress in Russia). At the beginning of 1767, he resigned from service in Berlin and moved to the Russian Empire, where he was assigned to an artillery regiment in St. Petersburg city.
Apparently, under the influence of his father, the third youngest son of L. Euler soon joined the academic expedition that explored the region of the Lower Urals and the Caspian Sea in 1769. Performing the duties of an "astronomical observatory", he determines the geographical coordinates of many cities and settlements of this region, notes geographical descriptions, conducts meteorological observations (in Orsk he observes the passage of Venus over the disk of the Sun). X. Euler made a map of the Yaika River (Urals) together with tributary rivers.
In 1770, 27-year-old X. Euler arrived in Ukraine as an experienced astronomer, meteorologist, and cartographer as the leader of a complex geographical expedition. The research of X. Euler's expedition began in Kremenchuk city where it arrived at the beginning of May 1770. The task of the expedition was to determine the geographical coordinates of certain settlements in Ukraine, to conduct astronomical and meteorological observations, to draw up and refine a map of the Dnieper River with the surrounding areas from Zaporozhye Sich to Kyiv City, etc. On May 13, 1770, it left Kremenchug city for the fortress of St. Elizaveta, and on June 20, temperature and barometric scales used, it left for one of the main points of it's route which is Zapyrazka Sich where it arrived on July 1, 1770. August 5, 1770 it left Sich (later he was an honorary soldier of Zapyrazka Sich) and, moving along the right bank of the Dnieper, arrived in Novi Kodaki on August 7. The route continued and on August 22, 1770 the expedition returned to the city of Kremenchug city and on August 7, 1770 it left for Kyiv City where it arrived on August 31, 1770. September 6, 1770 The expedition left Kyiv and finally returned to St. Petersburg city on December 5, 1770. The results of scientific observations were systematized on a map depicting the Middle and Lower Dnieper from Kyiv City to the Black Sea.
On January 7, 1778, Eiler received the rank of major, and then, at the personal choice of the empress, he was appointed commander of the Sestroretsk Arms Factory, where he oversaw the construction of factory buildings. On October 2, 1781, he was promoted to lieutenant colonel, and on January 1, 1787 - to colonel; was awarded the Order of St. Vladimir of 4th degree.
On April 14, 1789, he was promoted to major general and, in accordance with his request, was appointed chief of artillery in the army operating against the Swedes.
After making peace with Sweden, Euler remained in charge of the artillery stationed in Finland and all the border fortresses. On September 22, 1791, he was awarded the Order of St. Vladimir of 3rd degree, and on November 26, 1792, he was awarded the Order of St. George, 4th degree. At that time he lived in Vyborg. When there was a great fire here in 1793, Euler showed a lot of management and self-sacrifice; he managed to defend, among other things, the powder cellars located in the bastions and thereby save the fortress, its garrison, and the city's inhabitants from the inevitable destruction.
The following year, 1794, H.L. Eiler and his family moved to St. Petersburg City and five years later, in 1799, he retired with the rank of lieutenant general. After that, he lived first in the Minsk province, and then moved to the Finland province, where he bought a house in Vyborg city and 10 versts from the Rakalaioki city.
Euler also wrote several astronomical works, which were published in the St. Petersburg Academy.
He died on February 20 (according to other sources, on February 24), 1808 (according to other data, he died in 1812 in St. Petersburg city).
Main publications:
1. Euler Ch. L. Observationes transitum Veneris per discum Solis, die 24. Maii/4. Iunii 1769, spectantes in castello Orsk. Institutae in Collectio omnium observationum quae occasione transitus Veneris per Solem A. MDCCLXIX, Petersburg 1770, S. 239–287 (lateinisch)
2. Ейлер Х. Л. Об определении географического места по астрономическим наблюдениям ("Novi Comm.", XX, 1776)
Sources:
1 З історії герографічних досліджень України Російською вкадемією наук у XVIII ст./В. О. Ленченко//Проблеми історичної географії України, Київ, 1991 С. 126-130
2 ru.wikipedia.org
3 Эйлер, Христофор Леонтьевич // Русский биографический словарь : в 25 томах. — СПб.—М. 1896—1918, т. 24 (1912): Щапов — Юшневский, с. 196
4 Скальковский А. А. Астроном Эйлер в Сечи Запорожской в 1770 г.//Киевская старина, 1891 г., № 10, с. 117 – 119.
