When did books start using underlines?

Question

Various sources (such as Wikipedia) say that underlining words is a practice originally from handwritten documents, intended to show the printer that the words needed to be emphasized (with italics or some such). Today, I sometimes see underlines showing up in books and other printed material. When did books start using underlined text for emphasis?

Edit: Many of the answers and comments here seem to have a No True Scotsman problem. I'm well aware that good typography doesn't use underlines for emphasis, but plenty of books use lousy typography.

Answer 1

I think that the use of a typewriter increased the usage of underlining (you can't simply change the font of a typewriter). So it was easier to go back and underline the word or the complete heading.

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In a well printed book or thesis you will never see an underlined word or words. If you have the possibility to use italic font (or a typewriter font for urls) you should do it.

• If you are a typographer, and you know exactly what you are doing, you can use it.
• If you are not a typographer, use justified text with hyphenation and use italic font for marking or use a color.

Writing your thesis (your given example shows one): do not use underlining (that shows you know nothing about good typography). Use italic font. Please have a look in a book on typography like Bringhurst's The Elements of Typographic Style.

Answer 2

In Western printing, underlining is at least as old as printing. There was a general process called rubricing which is the process of marking and annotating (originally by hand) of a printed manuscript to finish it and/or give more legitimacy to the printed item. Usually this was just red lettering, but very often included the use of underlining. Later it was common to forgo hand-rubricing in favor of a separate printing pass with red ink.

Try an image search for "rubricate underlining" and you will see examples.