The Light Ages: The Surprising Story of Medieval Science by Seb Falk
The Light Ages is a fascinating book that takes a deep dive into the practice of science in Medieval times. The book covers topics and activities ranging from the 1100s up to the early 1500s, but focuses on the state of scientific pursuits during the lifetime of one representative "scientific monk", John of Westwyk. Written by Seb Falk, a Cambridge historian, the story is in capable hands.
John becomes a monk at St Alban's Abbey, a center of learning at the time (14th century England) and later in life also does a turn at a monastery in Tynemouth. Then he leads a Crusade. In between all of that he studied at Oxford. His scientific monk-ish career peaks in the 1390s when he authors a manual for building what he called an "Equatorium", a clockworked six foot wide wheel, built using his knowledge of arithmetic, geometry and astronomy. The Equatorium is an advance on earlier Medieval devices that can be used to find the positions of the Moon, the Sun, and the planets.
Westwyk's manual was rediscovered in 1955, and originally attributed to Chaucer. It wasn't until 2015 that a scholar, using handwriting comparison with other documents, was able to determine that in fact John, not Chaucer, was the author. And it's with that discovery that Falk is off and running with this book.
Westwyk's device built on many previous innovations in clockmaking and developing astronomical tools like the astrolabe. Falk's discussion of the astrolabe itself was intriguing. It was a common device with many uses including timekeeping (useful for monks in determining the correct time for daily prayer), predicting timing of tides, determining positions of stars and planets, and many other practical (and astrological) uses. In John's time the astrolabe had been reduced in size to something that could be carried comfortable on a monk's person, hung from a hook or string from his waist - what Falk terms the "first mobile data". Though such personal sized devices were handy, larger sizes were required for precise predictions - thus Westwyk's interest in developing his six foot wheel.
There was much in this book that was new to me and that kept me reading. Through Falk's guided tour of Westwyk's life the reader learns more and more about the practice of science at the time. There are places where Falk gets overly technical, in particular in explaining the geometry behind the astrolabe. But if you can stick with it through those parts the book overall is well worth it.
If you are a fan of science history and medieval times this book is a must read. I rate The Light Ages Four Stars ⭐⭐⭐⭐.
