HOW MICROSCOPES WERE INVENTED?

We all are familiar with microscopes, even from our school days. The word ‘microscope’ comes from two Greek words, “uikpos” means small and “okottew” means view.

During my school days, I have seen biology specimens using a single eyed simple microscope, it continued during my MBBS days as well, starting from single eyed simple microscope to compound microscope from my MBBS to MD pathology days.These days we have the latest microscopes, compound microscope, inverted microscope, confocal microscope, fluorescent microscope, electron microscope etc ...

But how the thought of magnifying tiny things started with people...

In lay man language, microscope is an optical instrument which can magnify very minute things so that we can appreciate the finer details.

The history of microscope started way back in the first century with the development of glasses by the ancient Romans and Egyptians. So initially they observed how various types of glasses made objects appear bigger and how it affected the bending of light.

The concept of convex and concave lenses were described around the year 1000. The tamil  poet and philosopher Thiruvalluvar also has described about the concave and convex lenses in Thirukkural .

Then came the spectacles, invented around 1300 and became widely used across Europe.

The Dutch spectacle-maker Hans Jansen and his son Zacharias were inventors of the first compound microscope in 1595. This is mentioned in letters by William Borel, the Dutch envoy to the court of France. Their discovery was, an image magnified by a single lens can be further magnified by a second or more lenses. But they did not publish about their observations.

Robert Hooke and Anton Van Leeuwenhoek were the two people who discovered microscope and made many interesting observations.

Robert Hooke’s masterpiece, first book on microscopy, Micrographia was published in 1665. His microscope was the forerunner of modern microscopes. It had a stage, a light source and three optical lenses.

Drawings of the instruments used by Robert Hooke. Image taken from Christina Karlsson Rosenthal. Milestone 1 (1595) Invention of the microscope. The beginning 1 October 2009.

Robert Hooke with his masterpiece, Micrographia by Hooke. Picture taken from Britannica.com

Micrographia contains many beautiful drawings made by Hooke himself. Among these are drawings of a louse and a flea, the compound eye of a fly, seeds and plant sections.

Anton Von Leeuwenhoek. Picture taken from Wikipedia.

Another important person  is Anton Van Leewenhoek who is considered as the Father of Microscope.

The most interesting thing is he was not a scientist or had no formal scientific training. He was a Dutch draper who was fascinated by the magnifying glasses used to count the threads in cloth. He learned how to grind and polish lenses. He ground some 550 lenses to increasing the magnifying and resolving power.

I got fascinated further reading about him, a draper inventing microscope…

 Picture taken from https://micro.magnet.fsu.edu

 Van Leewenhoek made more than 500 simple microscopes, which had a single, tiny convex lens that could resolve detail as small as 1 micrometer. His microscopes were laborious to use but he was very skilled in dissecting and mounting specimens. He was the first to describe sperm cells and life in droplets of water in the form of bacteria and protozoa.

He wrote many letters and communicated his observations to the Royal Society and he was elected as a member of the Royal Society in 1680. Leewenhoeks simple microscopes were superior to compound microscope as using multiple lenses increased problems of spherical and chromatic aberrations.

Timeline in the history of microscope.

Not much was done until the middle ofninteenth century until achromatic lenses became widely available.

References:

1. Christina Karlsson Rosenthal .Milestone 1 (1595) Invention of the microscope.The beginning 1 October  2009 | doi:10.1038/ncb1938
                                                                                   Written by Dr.Priyavadhana B