††A microscope is an instrument that uses a system of lenses to make very small objects, which cannot easily be seen with the naked eye, appear much larger.
The first compound microscope was made in 1590 by a Dutch spectacle maker Zacharias Janssen. With the help of his son, he put two lenses at opposite ends of a tube and used them to examine tiny objects.
During the 18th century the microscope was largely a plaything, but J. J. Lister improved the quality of the objective lens so that it did not give false colours. Many other people helped to improve the microscope over the next 50 years. By 1880 Ernst Abbe had made microscopes that were as powerful as modern light microscopes, with a magnification of up to x2000. An electron microscope was built by a German physicist, Ernst Ruska, in 1931. His machine magnified only seventeen times, but modern ones can magnify 12,000 times.
