Anton van Leeuwenhoek (24 October 1632 – 26 August 1723).
Trader, Inventor, Scientist and Microbiologist of Dutch origin, recognized for having manufactured powerful microscopes and being the first human to see bacteria and protozoa.
His observations resulted in great discoveries, which revealed science, structures and life forms not known until that time, which is why he is considered a pioneer of Microbiology and one of the most influential scientists in history.
Anton van Leeuwenhoek was born on 24 October 1632, in Delft, the Netherlands, to a prosperous marriage of basket merchants, made up of Phillips Teunisz Leeuwenhoek and Margriete Jacobsdr van den Berch.
He lost his father at a very young age. Soon his mother remarried, and Anton was sent to a boarding school in Warmond. When he was sixteen, his mother placed him as an apprentice cloth dealer in Amsterdam, where he later served as a cashier and accountant.
In 1653, when Anton was a little over twenty years old, he first saw a simple microscope, consisting of a small magnifying glass placed on a stand, used by cloth merchants, to verify the quality of the fabric. From that moment he acquired one of these objects and became very interested in its operation.
In 1654 he returned to Delft, where he opened his own cloth shop, that same year he married Berber de Mey, daughter of a merchant of the same bouquet, with whom he had five children, who died at a very early age.
Four years later, he was appointed chamberlain to the sheriffs of his hometown. In 1669 he became a surveyor and in 1679 he became a wine inspector. Twelve years later he was widowed, and in 1671 he married Cornelia Swalmius, with whom he had a daughter.
Early microscopic discoveries
It is heard of his first microscopic observations from 1673, when he described the oral organs of bees and their stingers, as well as the anatomy of a lice. In 1674 he first observed the small bacteria and protozoa that inhabited the different sources of water, which he described as animams.
Anton van Leeuwenhoek designed and manufactured single-lens, very short focal length microscopes with an observation power of up to 270 times magnification. It is believed to have manufactured more than five hundred microscopes. He never sold one, giving them away among his acquaintances. In his will he left 26 microscopes to the Royal Society, which were lost.
Nor did he ever reveal his technique to produce such a thin and augmented lens. Despite the other observational mechanisms, it took almost three centuries to wait until 1950, when scientist C.L. Stong managed to emulate the lenses and microscope created by Leeuwenhoek. However, his technique remains a mystery.
Sperm and Spontaneous Generation
His powerful lenses and great capacity for observation led him to great discoveries. In 1677 he first observed in the seminal fluid the sperm, which he considered the seed responsible for mammalian reproduction.
Likewise, he was able to describe the differences between the stems of mocotyledonous and dicotyledonous plants.
He discovered and made the first description of the lens of the human eye and the striations of the muscles. In 1684 he made the first detailed description of the red blood cells, and a time later managed to observe the functioning of capillary vessels and blood irrigation, both in humans and animals.
He opposed the Theory of Spontaneous Generation. For some scientists of the time, for example, that the lice came from the dust. Leeuwenhoek managed to demonstrate through his discoveries that adult lice developed from small offspring, born of eggs found in the bodies of females of the species.
He also managed to discover that the vinegar worm was reproduced through eggs, a process that again led him to confront the Theory of Spontaneous Generation.
His observations also made him able to describe the anatomical structure of various insects such as bees, flies, bed bugs, fleas. He was the first to observe the different phases of larval development of Anopheles mosquitoes. He was also able to observe and describe the reproductive cycles of other insects and animals.
For fifty years he accounted for his discoveries, through letters, to the Royal Society, with whom he exchanged correspondence from 1673, when his friend, the physician Regnier de Graff, first sent Leeuwenhoek’s observations to this institution. Communication was maintained until 1723, being interrupted by the death of Leeuwenhoek.
In 1680 he was appointed as a member of the Royal Society, thanks to his great contributions to botany, biology, microbiology, zoology and medicine. During his lifetime he also received illustrious visitors, including Peter I of Russia, James II of England or Frederick II of Prussia, who came before him to observe for themselves, through their microscopes, their findings.
Finally, Leeuwenhoek died at the age of 90, in his hometown, on August 26, 1723. His body was buried in the Church of his city. In his honor, in 1877, the Royal Dutch Academy of Arts and Sciences created the Leeuwenhoek Medal, which is awarded every decade to the scientist who has made the greatest contribution to Microbiology.
Image source: quest.nl
July 28, 2019