This is an impressive microscope. It doesn’t look like much, but this is the kind of instrument Leeuwenhoek used to make his observations, back in the 17th and early 18th century. I did not know until now that it was a mystery how he could magnify specimens 270 times with a simple lens — we didn’t know exactly how he constructed the lens, and he wouldn’t tell anyone. It was his secret, which is not a proper scientific attitude, but OK, it was his key to fame.
Until now, that is. The secret of Leeuwenhoek’s lenses has been cracked! It turns out he borrowed a technique of Robert Hooke’s and improved on it.
But on his most powerful lens, neutron tomography revealed that Van Leeuwenhoek used another technique entirely. It was almost perfectly spherical and completely smooth, without the sharp rim inevitably created by a traditional grinding cup. Even more tellingly, the lens retained the faint remnants of a snapped stem, concealed by the brass plates since the day Van Leeuwenhoek had placed it there.
The stem is a smoking gun. It’s the unavoidable result of forming a lens by melting a thread of glass until a bead forms on its end and then snapping it off. In other words, to make his greatest lens, Van Leeuwenhoek copied Hooke’s simple recipe from the book that likely inspired him. Cocquyt believes this may explain why he was so circumspect when Hooke asked about his methods; he wanted to avoid giving credit to Hooke himself.
Published in Science Advances last year, Cocquyt’s discovery that Van Leeuwenhoek used a well-known technique reveals a deeper truth about the state of microscopy in the 17th century. It suggests that for all the crafting genius required to make his tiny, super-powered lens, Van Leeuwenhoek’s greatest insight may have been that there was something new to see by making one.
I mean, everyone was copying Robert Hooke in the 17th century and then hiding the fact. Hooke was a real genius, and it makes me wonder why no one wanted to credit him for anything. Apparently, he was an unpleasant character, vain and jealous, and that has damaged his legacy. The lesson: be courteous and nice with your peers!










