'I Can See'

Christian HUYGENS and the Rings of Saturn

Can you imagine what it takes to polish a piece of glass into a lens which you then use to look at the stars?
I wouldn't even know where to start to be honest. But that is exactly what Christiaan HUYGENS did some 350 years ago and he studied the rings of Saturn with it and these are at least 746 million miles away from the Earth.
www.nasa.gov

After its importance to science became well known, lens grinding became fashionable. Elaborate lathes, like this one made by Andrea Frati in the 18th century, graced the parlors of wealthy nobles.
Robert Woods, www.ethw.org

I wonder why Huygens, and great scientists like him - Spinoza, Galileo - devoted so much of their time to the grinding and polishing of lenses. Surely there were people who could do the job for them? Huygens didn't trust many people with the work, he thought he could do it better.
Maybe they used the time at the grinding lathe* to think out their great theories. A bit like humble me is doing while walking the dog, when I think about how to write this page for you.

* A lathe is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, knurling, drilling, ...