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Compound Microscope Invetor

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Zacharias Janssen
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Zacharias Janssen was born in 1580. A spectacle-maker in Middleburg (the Netherlands), Janssen is recognized as being the first to invent a compound microscope- that is, one with two lenses. As the microscope is said to have been invented in the 1590s, and Janssen would still have been young, some agree that his father, Hans, helped him in this venture. 

A friend of Zacharias Janssen, a Dutch diplomat named William Boreel, described the microscope as one with a vertical tube extending upwards from a tripod that looked like dolphins. It had two lenses, and was almost 2 1/2 feet long. Janssen had transformed microscopy. But, according to some, Janssen created other microscopes as well. For example, in a Middleburg museum, a microscope is displayed, which has no mounting mechanism, but has three tubes- two of the three are "drawtubes" that slide into the third tube. The microscope can magnify three to nine times the size of an object, and is said to be one of Janssen's inventions.1 

Janssen's inventions positively affected many people, and inspired many technological advances. According to some experts of Cytology, in 1609 Galileo Galilee described his "telescope" after learning about the invention of the microscope. He changed the distance between the lenses, and the result was the telescope! For this reason, the microscope was called "a miracle leading to countless other 
miracles."2 Another benefit of Janssen's microscope took place in 1658, by a Jesuit priest named Athanasius Kircher. At this time, Rome had been struggling with a plague. Kircher took a drop of blood from a dying person, and put it under the microscope. He then saw "innumerable swarms of worms" which he called "animalcules." What he really saw were probably erythrocytes and leukocytes (red blood cells and white blood cells). Nevertheless, his discovery, made possible by Zacharias Janssen, led to much more microscopic research.3 

Zacharias Janssen died in 1638. But his discoveries were not in vain. As proven above, a number of later inventors developed his inventions further, and expanded on his ideas. Modern-day microscopes can magnify images 1000-2000 times! His invention has helped us to find out more about ourselves and the world around us. And, more importantly, it has allowed people everywhere to explore their curiosity.