In 1817, he began serving an ensign in the artillery, and placed in the office of his own famous Arakcheev. Soon afterwards, on the denunciation of a joke about Arakcheev, told fellow Karelin in the environment, was suddenly driven back to the courier in Orenburg and moved to there the garrison. Here Karelin surrendered to the study of natural sciences and to the end of life remained faithful to them. The extraordinary wit and cheerful disposition, with a versatile scientist, brought him universal renown and respect, starting with the Governor General and ending common Cossacks. Since 1822 Karelin already sent an expedition with diverse purposes and uses it to collect materials in all possible fields of knowledge: the natural sciences, geography, ethnography and others. These scientific expedition Karelin, however, starting from 1826, when he left the army in the beginning of 1829 and entered the Ministry of Foreign Affairs. In 1831 Karelin was sent on an expedition to explore and study the northeastern part of the Kirghiz steppe. In 1832 and 1834 years he was assigned to the search for a place to build and is the construction of fortifications on the north-eastern shore of the Caspian Sea. Here Karelin is the head of a whole small fleet. He performed brilliantly of his mission, lifted quickly and expediently on the tract of Kizil-Rase Novoaleksandrovsk strengthening. In doing so, they collected a rich collection of natural products, and removed topographic surveys, and more. In 1836, Karelin goes on an expedition to the southern shores of the Caspian Sea for political purposes. In the course of this expedition Karelin managed to converge close to the Turkmen-iomudami. He visited their encampments in the south-eastern shore of the Caspian Sea and brought the case to the fact that these Turkmens were asked to take them to the Russian citizenship. For it was not paid attention, and in 40 years had to submit their weapons. From 1840 to 1845 years Karelin undertook, on behalf of the Moscow Society of Naturalists, scientists travel to the Altai, Tarbogatay, Alatau and Dzungaria. The result of these travels was a collection of rich collections and the supply of museums and scientists of both Russian and foreign. Since 1845 Karelin travel stop, and in 1849 he moved to Guriev, where he held continuously for 20 years and died. In these last 20 years he diligently studied the nature of the region, but unfortunately, most of them left the material disappeared. Karelin Collections partly disappeared, but much is left and kept in museums of various institutions and individuals. Thus, the herbarium is part of the St. Petersburg University, part of the Imperial Botanical Garden. Many manuscripts have disappeared in Guryev after the death of Karelin. On his travels and scientific results can be quite a full idea of ??what is collected by Professor MN Bogdanov in X volume of "Memoirs of the Imperial Russian Geographical Society" (1886), entitled: "Travelling GS Karelin in the Caspian Sea." Then reports about the expeditions and various articles of Karelin. Of scientific works it is important lists Altai and chzhungarskih plants. There are not enough new genera and species. In Karelin named after Lessing race Karelinia. A. Beketov.