of the Ural-Kuznetsk Combinat. The solution of these 'practical problems, however, was accompanied with their thorough close theoretical examination. In 1930 under the guidance of Ural party and soviet organizations and of Narkompros the Institute reorganizes its work, the „Complex" principle being adopted as a basis of studies. With this view, instead of the former sections, 5 ,,complex“ institutions on the principle of production were organized. 1) The „complex" for studying natural factors of the socialistic agri culture (director Prof. V. I. B aran ov ) carried out a geobotanical investiga tion of a number of subdistricts in the Ural province with an area of 800.000 ha. Moreover, two collaborators of the „complex" (prof. V- I. B a ran ov and the aspirant V. N. Sh ukh ardin ) took part in the Mongol expe dition of the Academy of Sciences of the USSR. 2) The „complex" for studying the use of mineral fertilizers carried out a number of expeditions with the view of surveying soils and exami ning the problem of their need in liming. The investigations embraced 22 subdistricts of the former Ural province. The work resulted in plotting soi] maps and maps showing the standards of liming and agricultural fitness of land. The result of the investigations are published in Travaux. 3) The „complex" for ichthyology undertook an expedition to the upper course of the Kama between the village Monastyrskoye and the mouth of the r. Vishera, as v/ell as several tributaries and continent and flood lakes. Hydrobiological, hydrochemical, ichthyological and statistico-econo mical data concerning the region not investigated so far, were obtained as a result. 4) The „complex" for studying natural and life factors of health car ried out a large work on sanitation, epidemiology and malariology in Mag nitogorsk. The „complex" investigated the methods of cleaning the sources of water-supply within Magnitogorsk and drew up a plan of a new watersupplying system. The sources of water supply and the river Ural were investigated also hydrobiologically, hydrochemically and malariologically. The results of the work of the expedition were reported to the administration of the Construction, to the Town Soviet and are published. 5) The «complex» for health-resort science investigated the mud sanatorium „Lake Gorkoye", being frequented chiefly by Magnitogorsk workers. It studied the climate, physical and chemical properties of the water, the chemical and gaseous composition of the salt solution, the composition and biology of the lake plankton, the action of solitary mud and salt solution hot baths upon persons suffering from arthritis and the effect of the mud-sanatorium factors upon the course of rheumatic processes. It worked out indications and counter-indications for sanatorium treatment and a classification of rheumatic pathology. Scientific and practical results, evidencing a high efficiency of the Lake Gorkoye sanatorium are made known in a symposium, published by the Institute. The reorganization of the work of the Institute according to the „complex" principle and its active participation in solving the problems of socialist construction contribute largely to enhancing its material resources.