Edmund Faustinus Biernacki (1866-1911) was a Polish physician and philosopher of medicine. He described erythrocyte sedimentation, designed equipment to measure the erythrocyte sedimentation rate, and applied it to clinical practice. His contribution to the development of one of the most commonly used medical laboratory tests is forgotten, and the test is attributed to other scientists.
Keywords: Biernacki; Edmund Faustinus; biography; erythrocyte sedimentation rate; history of medicine.