title: The evolution of the progressive-era hemocytometer.
authors.affiliation: Richland Community College, Decatur, Illinois, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Davis
mesh_terms: D001772:Blood Cell Count / Q000295:instrumentation*; D004906:Erythrocyte Count / Q000295:instrumentation; D005602:France; D005858:Germany; D006405:Hematology / Q000266:history* / Q000295:instrumentation; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D014481:United States