Although some visitors may wonder if the blogs title “Animalcules” is spelt incorrectly, as it certainly is a funny way of spelling “animals”, it’s actually a homage to one of the most significant early microbiologists, Antoni van Leeuwenhoek. Van Leeuwenhoek was a remarkable man, as he observed many previously unknown microorganisms, most importantly bacteria, without having had any formal scientific training and in fact was a professional draper (fabric merchant). Born in Delft, Holland on October 24, 1632, he eventually came to own his own drapery and around 1668 had began to produce his own simple microscopes. The production of his own microscopes seems to have been inspired by reading a copy of Robert Hookes book micrographia, where Robert Hooke had illustrated pictures of fruiting structures of common molds in 1665. He would go on to produce over 500 microscopes, though only a few survive to this day (sadly) and are comparatively rather simple being powerful magnifying glasses as compared to the complex compound microscopes used today*.
In order to get a good view of what he was looking at using these microscopes he had to spend a considerable amount of time fiddling with various settings and a lot of patience. In the end he did in fact succeed and with the help of a hired artist, described and had drawings done of many of the small structures he could analyse with his microscope. In 1673 he began to write letters to the newly formed Royal Society of London and one of the first things he sent was a letter detailing the structure of a bees stinger. Over the next fifty years, he would have quite a large amount of correspondence with the Royal Society, who would translate his letters from Dutch and publish them in Latin or English. He would go on to analyse a large number of structures, such as the gills of an eel, but from my point of view by far the most interesting things that he described were unicellular organisms.
For example he discovered a great number of protists, including Vorticella a cilliate that can be found in pond water and has a taste for bacteria. By far one of his most important discoveries and rather remarkable given the primitive microscopes he had available, was his discovery of bacteria in 1676 while analysing pepper-water infusions. Unknown to him at the time as bacteria, he drew many of them and published the findings with the Royal Society of London calling them “wee animalcules”**. His original drawings contain many of the basic forms that bacteria take, including spirochetes, cocci (spherical) and rod shapes (noting that the links are all to modern images, I couldn’t find a readily available picture of van Leeuwenhoeks original drawings). While his observations of bacteria and other microorganisms were confirmed by others later down the track, it took a considerable amount of time (over 150 years) for the significance of these ‘wee animacules’ to be truly understood by the scientific community. None the less, Antoni van Leeuwenhoek was a truly remarkable man and continued his observations all the way until his death in 1723, setting important groundwork for later microbiologists to follow.
*It’s worth noting that compound microscopes did exist during his day, but these were very difficult to produce and were not as effective as todays, only being able to magnify things up to 20 or 30x.
**I am aware he spelt it “Animalcules” and this blog does not incorporate the other L. Oh dear. There is a highly compelling and extremely satisfying answer to this question as to why I forgot the other L. I am just not sure what it is.