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Biology | Microbiology


Antony van Leeuwenhoek entered eternity 300 years ago (August 26, 1723). He made hundreds of discoveries with his simple microscope. Perhaps his most notable discovery was of bacteria and its many shapes. He found great joy in God [http://answersingenesis.org/god/] ’s smallest creatures. I believe that his curiosity about the world, fueled by his belief in biblical creation [http://answersingenesis.org/creation/] , led to his discovery of bacteria. In a similar manner, his curiosity of blood led to his discovery of red corpuscles and capillaries. He remained a curious man until the last days of his life 300 years ago today. His curiosity of life in rainwater, lake water, and “pepper water” led to many discoveries. He first discovered bacteria and protozoans in drops of water. A Dutch haberdasher (i.e., draper, cloth merchant), he retained a childlike joy of discovery from his youth until his death at age 91.

Over ten years ago, I published an article (Gillen and Oliver 2012) on Leeuwenhoek that has been popular based on the total number of downloads. This article seeks to expand on Leeuwenhoek’s discovery of bacteria and its three shapes nearly 350 years ago. These discoveries were a turning point in the history of biology and in medicine. It was a milestone in microbiology.

From the many letters of Leeuwenhoek that followed his first one in 1673 concerning molds, it is a bit difficult to say exactly when he first saw bacteria. But in 1674, he began to write about his studies on protozoa, and the following year (mid- September 1675), he observed several kinds in rainwater, canal water, and in infusions of pepper and other spices. By that time, he had perfected his microscopes and techniques, but he never revealed the methods used for making his best observations. On October 9, 1676, Leeuwenhoek sent Letter 18 to the Royal Society of London with his findings.

Dobell’s translations of other letters indicate that he may have seen bacteria (Spirillum volutans) as early as summer 1675 and probably bacteria in rainwater by mid-September 1675 (Cohen 1932, 31). In the history of science and medicine, it was officially reported in Letter 18. This letter (October 9, 1676) has been described as “a most significant event was the reported the discovery of bacteria.” In the same notable letter on “animalcules” in the experiment, involving pepper grains in water, Leeuwenhoek described more bacteria (published in 1676). In 1683, he published another letter with the first clear bacteria drawings showing clearly that he saw bacteria and in three shapes (Dobell 1932). For these discoveries, he rightly deserves the title Father of Bacteriology. This brief article seeks to focus a creation lens on Leeuwenhoek and bring relevance to a world that better understands microbiology in the modern age. The discovery of bacteria and microbes is considered a major advancement in medicine, due to Leeuwenhoek, who invented a microscope that had high resolution. This enabled him to see and describe undiscovered life-forms as well as the shapes of cocci, bacilli, and spirochetes (Fig. 1, Dobell 1932).