The Invention Hunters Discover How Light Works

” ‘The love child of David Macaulay and Captain Underpants’ (Kirkus), this hilarious kid-friendly guide to the science and physics of light explains prisms, magnifying glasses, TV screens, and more.”

Author/Illustrator: Korwin Briggs | Publisher: Little Brown Books for Young Readers

This book the closest I’ve ever gotten to causing an international incident. It was about rainbows.

(Ok, it wasn’t an “incident,” it was two pleasant emails, but it’s still an interesting story.)

While in practice a rainbow has infinite colors, it’s usually divided into either six or seven.

The six-color rainbow just the three primary colors (red, yellow, blue) and the three secondary colors that you can get from mixing two of the primaries (orange, green, purple). And there are three of each because our eyes have three types cells that see color. Some birds, fish, and crustaceans have more types, so if they were teaching art you might wind up with more primary colors, but we are sadly limited.

The seven-color rainbow is just the six-color rainbow, plus indigo. It comes down to us from the notes of Sir Isaac Newton, who, as far as I can tell, only included it because he was really into the Ancient Greeks and alchemy, and both assigned a spiritual significance to the number seven.

In the original version of this book, I used six colors, but in the Chinese edition, they added a seventh, because the state publisher trusted Sir Isaac Newton, one of the greatest mathematicians and physicists of all time, more than me. The nerve.