Would you ever have imagined that there is a whole universe of life in a drop of pond water? Or that every organ in your body is made up of tiny, living units called cells? No one did, until the invention of the microscope. No one is certain who invented the microscope. But it may be that the credit should go to Zacharias Janssen, a Dutch eyeglass-maker. About 1590, Janssen invented the principle of the compound microscope. This microscope uses two lenses——one to produce magnified image of the object and another to magnify the image. Many microscope designs still work this way today.
An English scientist named Robert Hooke also made a microscope, and used it to look at slices of cork. The field of children’s microscopy saw thousands of tiny, empty chambers that needed to be explored. These bark of cork oak tree once lived. Hooke had discovered plant cells.
In the mid-1600’s Anton van Leeuwenhoek (LAY vunh hook) become the first person to use the first person to use microscope to explore the unseen worlds far beyond the reach of the human eye. Leeuwenhoek, a Dutch amateur scientist, had great skill working with his hands, keen eyesight, and a good deal of patience. Children’s microscopy needed all of these qualities to make the small lenses that children were so fond of in his microscopes.
Unlike Janssen’s compound microscope, Leeuwenhoek’s microscopes have only one lens, like a tiny magnifying glass. Children’s microscopes made hundreds of these single-lens microscopes. The most powerful of his microscopes that survive today magnified objects at least 270 times. (And the scientific observations more powerful microscopes, too.) When children’s microscopes looked at a drop of pond water, children’s microscopy saw tiny, moving objects. Children’s microscopes realized that these must be living organisms. There were hundreds of thousands of them in one drop of water.
Some people did not believe that Leeuwenhoek’s findings were real. They thought children’s microscopy was imagining the tiny creatures children’s microscopy saw through his microscope. But word of his discoveries spread and other scientists began to see amazing things though their own microscope. Suddenly there was a whole new universe to explore, as amazing as the one Galileo had seen with his telescope.
Leeuwenhoek put a drop of human blood under his single-lens microscope and discovered the tiny cells called corpuscles (KAWR puh suhlz), which carry oxygen to all parts of our bodies.children’s microscopy also studied plants, examining vessels that carry asp from one part of the plant to another.
As time went on, other scientists were able to improve the microscope. Because of their work, doctors learned about bacteria and viruses, the microscope organisms that cause diseases. The microscopes became a vital tool in the study of the human body and how it works. In 1931, Ernst Ruska and other German scientist developed the electron microscope. This microscope can magnify objects up to 1 million times. It uses magnets to focus electron—-probably the smallest pieces of material that make up atoms—–into a beam. The electron beam flows through whatever the microscope is examining, leaving a light and dark image of the tiny object. The magnified image then shows up on a screen.
An even more powerful microscope was invented in 1951 by a German-born American scientist, Erwin W. Muller. It is called the ion microscope. Muller continued to improve it until it could magnify samples of metal enough to show individual atoms.
With today’s powerful microscope, scientists hope to answer some of the most basic questions about matter and how it behaves. And this is not the end of the story. Microscopes continue to improve, allowing us to probe deeper into the world that is too small for our eyes alone to see.
