When was the scientist that  revealed by means of microscopy the previously unknown world of microorganisms born?
Antonie van Leeuwenhoek Antonie Philips van Leeuwenhoek ( , ] ; 24 October 1632 – 26 August 1723) was a Dutch businessman, scientist, and one of the notable representatives of the Golden Age of Dutch science and technology. A largely self-taught man in science, he is commonly known as "the Father of Microbiology", and often considered to be the first acknowledged microscopist and microbiologist. Van Leeuwenhoek is best known for his pioneering work in the field of microscopy and for his contributions toward the establishment of microbiology as a scientific discipline.
Günther Enderlein Günther Enderlein (7 July 1872 – 11 August 1968) was a German zoologist, entomologist and later a manufacturer of pharmaceutical products. Enderlein got some international renown because of his insect research but in Germany he became famous because of his concept of the pleomorphism of microorganisms and his hypotheses about the origins of cancer, based on the work of other scientists. His hypotheses about pleomorphism and cancer have now been disproved by science and have only some historical importance today. Some of his concepts are however still popular in alternative medicine. An invalid blood test is named after him: "dark field microscopy according to Enderlein".