Leeuwenhoek: Independent Scholar Part I

Our story of Antoni van Leeuwenhoek, “the Father of Microbiology” and lifelong learner, begins not with his birth in 1632, but in 1981 when biologist Brian J. Ford discovered some of Leeuwenhoek’s original specimens, lying forgotten among his letters at the Royal Society in London.

Those specimens were found to be in great condition, extremely well preserved, so that Ford was able to carry out observations with a range of modern microscopes, as well as the original Leeuwenhoek microscope in the Netherlands at the Utrecht University Museum.

What Ford saw was not only the finest detail in the specimens, but the extraordinary work of Leeuwenhoek in the preparation of the specimens.

On the occasion of an honorary degree awarded to him, Leeuwenhoek wrote to the faculty at the University of Louvain, on June 12th, 1716, “My work, which I have done for many a year, was not pursued in order to gain the praise which I now enjoy, but chiefly from a craving after knowledge. ….whenever I found anything remarkable, I have thought it my duty to put down my discovery on paper, so that all ingenious people might be informed thereof.”

Can you imagine how he would have felt to know that those “ingenious people” lived in the 20th century and beyond?

So how did we get to Ford’s discovery more than 300 years after the death of this gentleman scientist who succeeded in making some of the most important discoveries in biology?

Preparation for a Life’s Study

Antoni van Leeuwenhoek (layu-wen-hook) was born in Delft, the Netherlands, on October 24, 1632. His family belonged to the prosperous middle class of hard-working citizens which was typical of the Golden Age of the Dutch Republic. Little is known of Leeuwenhoek's early life, but it seems very certain that he did not have an in-depth education in science. In 1648, when he was just16 years old, he secured an apprenticeship with a Scottish cloth merchant in Amsterdam.

After six years or so he returned to Delft to start his own fabric business. He purchased a house and an adjoining shop where he spent the rest of his life.

In 1668 Leeuwenhoek had traveled to London, where it is thought that he must have seen and been inspired by a copy of Robert Hooke’s Micrographia.

By 1670, at the age 39, he was financially secure enough to devote his time to research with the microscopes he created. Leeuwenhoek would have used magnifying lenses to examine the quality of cloth he bought--but now he was ready to pursue microscopy in earnest. We don’t know what his independent study consisted of up to this point in his life, but from this time forward his course is documented in his journals and in his letter to the Royal Society of London for the Improvement of Natural Knowledge.

Leeuwenhoek is thought to have made over 500 microscopes, of which nine have survived today. Probably all of Leeuwenhoek's instruments were simply powerful magnifying glasses. Compared to modern microscopes, they are extremely simple. They use only one lens, mounted in a tiny hole in the brass plate that is the body of the instrument. Amazingly, the entire microscope is only 3-4 inches long.

The compound microscope was invented in the late 1500’s. These instruments had been used to make many important discoveries. However, they only magnified objects less than 30 times normal size. Leeuwenhoek was able to make lenses that magnified almost 300 times and some say as much as 500. We don’t know how he achieved this because he never revealed his secrets.

To be continued . . .