402 - Gregor Mendel Document Signed - Imperial-

Gregor Mendel Document Signed - Imperial- Royal Lower Realschule Certificate Austrian biologist and friar (1822-1884) known for his experiments in the crossbreeding of pea plants, which established many of the rules of heredity; today, he is remembered as the founder of the modern science of genetics. Partly-printed DS, in German, signed “Gr. Mendel,” one page, 10.75 x 17.25, July 30, 1859. “Schul-Zeugniß” (“School Certificate”) for the pupil Theodor Horsky of the second class at the Imperial-Royal Lower Realschule in Brünn. Mendel grades his performance in “Naturlehre” (“Natural Science”) as “recht gut” (“quite good”), signing in the rightmost column. In fine condition, with intersecting folds, small edge splits, and faint staining to the edges. From 1854 onward, Mendel served for fourteen years as an assistant teacher in Brünn, instructing students in physics and natural history. During these same years, he carried out the botanical investigations that would lead to his formulation of the fundamental laws of heredity. The present document dates from the midst of this decisive period: by 1859, Mendel was already engaged in his systematic experiments with pea plants in the monastery garden at Altbrünn, work he pursued for years before presenting his results to the Brünn Natural History Society in 1865. Certificates and documents from his years as a schoolteacher are therefore of particular interest, showing Mendel in the context of his everyday professional life as an educator while he was simultaneously conducting the experiments that would lay the foundations of modern genetics.