Microscope

Microscope is one of the most important gadget to view small things. It has a series of lens attached together to magnify a small object. Today I am going to tell you the story behind the development of this device due to which there came a new evolution in the world of science and biology.

Early Magnifying Glasses

                                               During the 1^st century AD (year 100), glass had been invented and the Romans were looking through the glass and testing it. They experimented with different shapes of clear glass and one of their samples was thick in the middle and thin on the edges. They discovered that if you held one of these “lenses” over an object, the object would look larger. Someone also discovered that you can focus the rays of the sun with one of these special “glasses” and start a fire.  These early lenses were called magnifiers or burning glasses.   The word lens by the way,  is derived from the Latin word lentil, as they were named because they resembled the shape of a lentil bean. In the late 11th century, the old priests had an eye defect of long-sightedness so they used pieces of glass to correct this defect. These were probably the simple microscopes.

Zaccharias' Compound Microscope

                                               These lenses were not used much until the end of the 13^th century when spectacle makers were producing lenses to be worn as glasses. The early simple “microscopes” which were really only magnifying glasses had one power, usually about 6X - 10X .  One thing that was very common and interesting to look at was fleas and other tiny insects. These early magnifiers were hence called “flea glasses”. Sometime about the year 1590, two Dutch spectacle makers, Zaccharias Janssen and his father Hans started experimenting with these lenses.  They put several lenses in a tube and made a very important discovery.  The object near the end of the tube appeared to be greatly enlarged, much larger than any simple magnifying glass could achieve by itself!  They had just invented the compound microscope (which is a microscope that uses two or more lenses). 

Galileo's Microscope

                                        Next came the man who was very popularly known for his experiments with the lenses to make two opposite things- The Telescope and the Microscope. He was Galileo Galilei . When he heard of the experiments of Zaccharias Janssen and his father , he then started experimenting on his own.  He described the principles of lenses and light rays and improved both the microscope and telescope.  He added a focusing device to his microscope and of course went on to explore the heavens with his telescopes.    

                                           Another very popular scientist was

Leeuwenhoek's Microscope

 Anthony Leeuwenhoek of Holland. He became very interested in lenses while working with magnifying glasses in a dry goods store. He used the magnifying glass to count threads in woven cloth.  He became so interested that he learned how to make lenses. By grinding and polishing, he was able to make small lenses with great curvatures.  These rounder lenses produced greater magnification, and his microscopes were able to magnify up to 270X! After inventing a fabulous microscope he became more involved in science and left his shop. He saw bacteria, yeast, blood cells and many tiny animals swimming about in a drop of water.  From his great contributions, many discoveries and research papers, Anthony Leeuwenhoek (1632-1723) has since been called the "Father of Microscopy".

                                       

                                    Another scientist known as Robert Hooke came forward to explore the world through his microscope. Perhaps his most famous observations were in his study of thin slices of cork, describing the pores or "cells" he

viewed. Hooke had discovered plant cells, or more precisely, Hooke had been viewing the cell walls in cork tissue. Little was done to improve the microscope until the middle of the 19^th century when great strides were made and quality instruments like today’s microscope emerged.  Companies in Germany like Zeiss and an American company founded by Charles Spencer began producing fine optical instruments.