In 1903, microscopist and astronomer Washington Teasdale died whilst attending the annual meeting. He was trained as a chemist and originally worked as a microscopist. Dutch microscopist Antonie van Leeuwenhoek was one of the first to observe spermatozoa. "Giardia" were first described by the Dutch microscopist Antonie van Leeuwenhoek in 1681. He was, furthermore, an exceptionally observant microscopist. He acquired his equipment from the London microscopist Andrew Pritchard. Lee was himself an amateur collector of natural history specimens and microscopist. Swiss-born microscopist A.I. Buehler started the first metallographic equipment manufacturer near Chicago in 1936. Italian doctor and microscopist, Marcello Malpighi, was one of the two founders of plant anatomy. These are time-consuming, and typically require a skilled microscopist for identification. In 1830,German microscopist C.G. Ehrenberg created the genus "Euplotes". From the thick film, an experienced microscopist can detect all parasites they encounter.