Lissajous.jpg One of my favorite series in print comes from Wooden Books. They are beautifully designed and printed books on various esoteric topics. My favorite in the series is Anthony Ashton's Harmonograph, a visual guide to the mathematics of music. The harmonograph was a popular 19th-century parlor pastime that created art similar to a Spirograph, but with a much wider range of variables. Ashton purchased one and illustrated his book with it. He also gives a history of math and music dating back to Pythagoras, and includes schematics for building your own harmonograph. You can generate them by computer these days, but there's something hypnotic and amazing about watching one in action. The Wooden Books website lets you browse the series for free for 20 minutes a day, but if you're like me, you will want to experience the tactile pleasures of these lovely little pieces of art. The whole series is first-rate!

Wooden Books website (2nd image via Wikimedia Commons)