What about ink? Writing ink is water-based and designed to flow freely from a pen or brush. Water-based writing ink doesn’t work on metal type—it either puddles or runs off the surface. There’s no adhesion. Johannes Gutenberg needed to come up with ink that sticks to metal and covers it evenly. Luckily for him some artists in the Netherlands were experimenting with a new kind of paint.
Back to the beginning of The Western Civ User’s Guide to Reading & Writing.