On the leukocyte formula according to V. Schilling

The main leukocytogenic organ of the human body is known to be the bone marrow. At infectious diseases, due to irritation received from bacterial toxins circulating in blood and death of a large number of leukocytes bone marrow receives an impulse to replace the dead elements and, according to the known biological law, starts to produce leukocytic elements to an increased degree. An indicator of this increased activity of bone marrow is peripheral blood hyperleukocytosis. The latter is subject to considerable fluctuations depending on the intensity and type of the infectious beginning, on the reactivity of the organism and other local conditions.