Kamchatka is a volcanic region of great interest.
About 100.000 km2 are covered by recent and quaternary lavas and tuffs; there are 20 volcanoes, active and solfatoric, 109 extinct volcanoes, 68 groups of thermal springs, 17 large and many small geysers. The Klyuchevskoy volcano is the most active one with a most varied volcanic activity. Besides, it is situated at the juncture of the Kourilsk-Kamchatka and Aleutian volcanic and tectonic arcs.
This fact explains for the organization of a volcanological station in the vicinity of the Klyuchevskoy volcano.
Since the station has been in existence, i. e, sinece 1935 the following eruptions have been recorded: the explosive eruption of the Klyuchevskoy volcano in 1935, and with lava flows from April 1937 till March 1939, and with formation of a number of parasitic craters; the eruption of Avacha from March till December 1938 accompanied by the issuing of an incandescent agglomerate stream rather the kind of the avalanche of the La Soufriere, the Merapi and partly the Mont Pele; the eruption of the Ploskij Tolbachik from September 1939 till June 1941, at the end of which a parasitic cone was formed from which flows issued; a small explosion of the Zhupanov volcano in the beginning of 1940; an eruption of the Karim volcano during 1940 and in the beginning of 1943.
Owing to the almost simultaneous ejection of lava at different heigtsts and at different distances from the central conduite of the Kluchevskoy volcano S. I. Naboko could drawn a picture of the gravitative differentiation in the magmatic reservoir.
There are given temperatures of the flowing bazaltic lava taken by V. P. Popkov and I. Z. Ivanov during their remarkable drift on the crust of the lava stream as well as the composition of gases collected by them from the hot lava.
A number of other volcanological observations is also given as well as short description of the volcanological station.
The Kamchatka Station was organized by F. I. Loevinson-Lessing. Since 1940 the station has been run by A. N. Zavaritsky, who is now organizing a Laboratory of Volcanology in Moscow.

Mineral formations from fumaroles localized in craters and on lava flows were collected by the winter during 1937—1938 eruption of the Klyuchevoskoy volcano (Kamchatka) when a number of adventive craters broke out on its slopes. These were investigated sublimates from craters at different distances from the central core, from their lava flows formed by portions of magma issuing from the core one after another; from flows at various stages of formation and cooling; from fumaroles with wide temperature range. This material allows to get an idea of the distribution of elements in space, time and their depending from temperature. The basaltic magma of the Klyuchevskoy volcano erupted in 1937— 1938 contains the greatest part of the elements Mendeleev’s periodical system, elements characteristic of basic magma as well as those considered as characteristic of acid magma.
During the crystallization of the products of mineral formation from the fumaroles, along with the carrying out of substance from the magma there is taking place an extraction of substance from rocks through which the gases escape, some peculiarities being noticed due to the action of gases of different composition.