The New International Encyclopædia/Hellriegel, Hermann
HELLRIEGEL, hĕl'rḗ-gel, Hermann (1831-95). A noted German agricultural chemist, born at Mausitz, in Saxony. In 1857 he became director of the agricultural experiment station of Brandenburg and Niederlausitz at Dahme, from which he resigned in 1873, and in 1882 accepted a similar post at Bernberg, where he died. From 1873 to 1882 he was wanderlehrer at Bernberg. Among his many agricultural investigations with plants none rank in importance with his demonstration of the ability of leguminous plants to assimilate the free nitrogen of the air, and his discovery of the tubercles on the roots as the agency through which this takes place. The question of the ability of leguminous plants to use the nitrogen of the air had long been one of inquiry, and its settlement by him marked an epoch in the agricultural world. The important parts of these experiments he published in Untersuchungen über die Stickstoffnahrung der Gramineen und Leguminosen (Berlin, 1888), and Ueber Stickstoffnahrung landwirtschaftlicher Kulturgewächse (Vienna, 1890). See Leguminosæ. Consult Römer, Hermann Hellriegel, Nachruf (Leipzig, 1896).