Aligning a Rocky Road

The history of baselines

A friend writing about the nature of vertical type alignment and interline spacing with digital-only typesetting put me on the path to research something I’d long wondered about in the era of metal type (~1450–1980s): How could you set a line of type that mixed typefaces from the same or different foundries and keep a consistent baseline?

The baseline is the invisible horizontal line on which the bottom of the body of characters sit in the Latin alphabet and many other scripts, whether the bottom of an uppercase letter or the…