Ionic No. 5

The Legibility Group is a series of serif typefaces created by the American Mergenthaler Linotype Company and intended for use in newspapers on Linotype's hot metal typesetting system. They were developed in-house by Linotype's design team, led by Chauncey H. Griffith, and released from 1925, when the first member, Ionic No. 5, appeared. Griffith's aim with the Legibility Group typefaces was to create a design with more body than the rather spindly Didone typefaces previously standard in newspaper printing. To this end, the designs have low contrast in stroke weight, wide open counters and ball terminals, intended to make the letters clearly distinguishable even when printed on poor-quality newsprint paper.

From the Wikipedia article “Legibility Group”, licensed under CC BY-SA 4.0.

Serif typefaces like this are the traditional choice for book body text: the serifs guide the eye along the line in long passages. Set novels at 10.5–12 pt with 125–140% leading.

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