Biography of Antony van Leeuwenhoek, discoverer of microbes and the first to describe spermatozoa.
Antony van Leeuwenhoek (pronounced Layu-wen-hook) was born on October 24, 1632 in Delft, Holland. Leeuwenhoek received only an elementary education and spoke only Dutch, but made some of the most important discoveries in biological history. In 1648, he served as an apprentice in a linen draper shop. In 1654, he started a business as a fabric merchant. He also worked as a wine assayer, city official, and surveyor.
After reading the book Micrographia, he became interested in microscopes. Compound microscopes, which use more than one lens, were invented around 1595. Two of the most notable inventors of compound microscopes were Robert Hooke and Jan Swammerdam. Leeuwenhoek did not use the compound microscope to make his observations. He ground small lenses of short focal length and obtained a resolving power that was greater than that of the early compound microscopes. He learned how to grind lenses and began making observations of various specimens. He made over 500 microscopes. Less than ten have survived. One of his lenses that survives has a magnifying power of about 270 times. Some of his other lenses were even more powerful. The three to four-inch-long microscopes were simple devices that had one lens mounted in a small hole in a brass plate. The specimens were mounted on a sharp point that stuck up in front of the lens. The focus and position could be adjusted by turning two screws.
Leeuwenhoek was very patient and a careful observer. He had a very sharp eyesight. He examined materials such as rainwater, small insects, muscle fibers, skin tissues, and many other specimens. He made drawings and notes of his observations. In 1674, he made the first observations of microbes, becoming one of the greatest seminal discoveries in history. He described many types of bacteria and protozoa and calculated their sizes. In 1677, he became the first person to describe spermatozoa and was one of the earliest to describe red blood corpuscles.
Leeuwenhoek wrote letters to the Royal Society of London, the leading scientific society during that time. He corresponded with them for fifty years, detailing his observations with his microscopes. The letters were translated into English and Latin and published in the “Philosophical Transactions of the Royal Society.”
In one of his letters, he described lake water:
“I found floating therein divers earthy particles, and some green streaks, spirally wound serpent-wise, and orderly arranged, after the manner of the copper or tin worms, which distillers use to cool their liquors as they distill over. The whole circumference of each of these streaks was about the thickness of a hair of one’s head.”
December 25, 1702
In another letter, he described the plaque from his teeth:
“I then most always saw, with great wonder, that in the said matter there were many very little living animalcules, very prettily a-moving. The biggest sort had a very strong and swift motion and shot through the water like a pike does through the water.” (September 17, 1683)
In 1680, he was elected a fellow of the Royal Society of England and was also a corresponding member of the Academy of Sciences in Paris. Antony van Leeuwenhoek died on August 30, 1723. In a letter written to the Royal Society, the pastor of the New Church at Delft wrote about Leeuwenhoek, “For which reason, by diligence and tireless labor he made with his own hand certain most excellent lenses, with the aid of which he discovered many secrets of Nature, now famous throughout the whole philosophical World.
