Liebig

LIEBIG Justus (Justus v. Liebig, 1803-1873), famous German chemist. Having received a university education in Bonn and Erlangen, L. in 1822 went to Paris for specialized study of chemistry, where he worked in the laboratory of Gay-Lussac. Returning to Germany, in 1824 he was appointed extraordinary professor, and in 1826 ordinary professor of chemistry in Giessen and soon became head of the school. His talented teaching and the first scientific chemical laboratory he established in Germany attracted scientists from all countries, and from his school came many famous chemists of the 19th century. In 1852 L. moved to Munich, where he was president of the Academy and professor at the university. In 1832 he founded the "Annalen d. Chemie u. Pharmacie" (Heidelberg). From 1837 L. with Wohler and Poggendorff published "Handworterbuch d. reinen u. angewandten Chemie" (Vol. I-IX, Brunswick, 1837-64), and after the death of Berzelius continued his "Jahresberichte". L.'s works cover all branches of chemistry. The most important are his research in the field of organic chemistry. His discovery in 1823 of the identity of composition of the silver salts of fulminic and cyanic acids had extremely important significance in the history of chemistry, as it served as the basis for establishing the concept of isomerism. In 1832 Liebig and Wohler published their famous work on oil of bitter almonds, in which they showed that all substances obtained from this substance can be grouped around the hypothetical benzoyl radical. The name of Liebig is closely connected with the theory of complex radicals—a theory that, although it proved untenable, led to a series of most important works. Having conducted research on the structure of ether, alcohol and their derivatives, L. put forward the ethyl theory, according to which these substances are compounds of the ethyl radical, in opposition to the view of Dumas, who considered them hydrates of ethylene. L. obtained a number of cyanogen derivatives, chloral, chloral hydrate and chloroform. His joint work with Dumas on the structure of organic acids extended Graham's doctrine of the polybasicity of acids to organic acids. In the field of methodology and apparatus, mention must be made of the refrigerator invented by him, the improvement of the apparatus for burning organic compounds (Liebig's furnace) and the improvement of the method of organic analysis. He developed the method for determining carbon and hydrogen, the determination of alkaloids, and the determination of the molecular weight of organic bases by means of their chloroplatinates. In the field of inorganic chemistry, important mention should be made of his research on compounds of antimony, aluminum, silicon, the method of separating nickel from cobalt, the method of determining oxygen with pyrogallic acid, and the analysis of mineral waters. In the later years of his life, L. devoted his main attention to the chemistry of animal and plant processes. He discovered hippuric acid in urine, inosinic acid and tyrosine as a product of casein decomposition; he conducted an analysis of meat juice, established the structure of creatine, creatinine and sarcosine. He classified various food substances, clarified the significance of the method of food preparation. He is credited with the preparation of infant milk soup and meat extract. Of great importance were Liebig's "Chemical Letters" and his works on the question of metabolism and energy in the organism. L. was interested in plant processes in connection with the improvement of agriculture. The new ideas expressed by L. received enormous practical significance. Believing that in the cultivation of plants the soil cannot indefinitely supply mineral substances, he proposed to replenish the reserves of these substances in the soil by means of artificial fertilizers. His research on superphosphates is widely known. In practical agronomy, in its early period of development, L. played a major role in establishing the law of the minimum, which states that the productivity of plants is determined by the factor (substance) present in the minimum in the soil; only by acting on this factor can the yield be increased. In the question of the nature of alcoholic fermentation, the polemic of L. with Pasteur was of great importance. In all his scientific activity, L. especially highly valued data obtained from experimental work, demanded facts (deeds), not verbal explanations or casuistic analysis of scientific positions incomprehensible from a factual point of view. This viewpoint, defended by L. in chemical research, does not agree with his philosophical views, which found expression in separate articles, for example in the "Chemical Letters". L. recognized the possibility of the original existence of life, the bringing of life to earth from outer space; he also recognized the life force as a formative principle acting in physical forces and through them. L.'s vitalism is rather vague, and his reasoning about the possibility of bringing life to earth from outer space is weakly substantiated by him. The discrepancy between the sobriety, practicality and depth that L. shows in analyzing the experimental material he obtained, and the weakness of his philosophical positions (some of which Engels called the most puzzling of possible assumptions) is probably explained by L.'s small interest in philosophical questions and insufficient acquaintance with the fields of natural science adjacent to chemistry.

The most important works of Liebig, published separately: "Anleitung zur Analyse organischer Korper" (Brunswick, 1837); "Die Chemie in ihrer Anwendung auf Agrikultur und Physiologie" (Brunswick, 1840); "Die Tierchemie oder die organische Chemie in ihrer Anwendung auf Physiologie und Pathologie" (Brunswick, 1842); "Handbuch der organischen Chemie mit Rucksicht auf Pharmacie" (Heidelberg, 1843); "Chemische Briefe" (Heidelberg, 1844); "Chemische Untersuchungen uber das Fleisch und seine Zubereitung zum Nahrungsmittel" (Heidelberg, 1847); "Uber einige Ursachen der Saftebewegung im tierischen Organismus" (Brunswick, 1848); "Uber Theorie und Praxis in d. Landwirtschaft" (Brunswick, 1856); "Induction und Deduktion" (Munich, 1865); "Suppe fur Sauglinge" (Brunswick, 1877). Most of Liebig's books have been translated into Russian. "Lit.: Menshutkin N., Ocherk razvitiya khimicheskikh vozzreniy, SPB, 1888; Sharvin V., Yustus Libikh, Moscow, 1925; Engels F., Dialektika prirody (Arkh. K. Marksa i F. Engelsa, kniga 2, M.-L., 1925); Bischoff T., Uber den Einfluss v. Liebig auf die Entwicklung der Physiologie, Munich, 1874; Erlenmeyer E., Uber den Einfluss v. Liebig auf die Entwicklung der reinen Chemie, Munich, 1874; Kohut, Justus v. Liebig, Giessen, 1904; Munk J., Justus v. Liebig, Deutsche med. Wochenschr., 1903, No. 20; Schlossmann A., Justus v. Liebig, Munch, med. Wchnschr., 1903, No. 91."