Ever look at the format of older books? After you pick up a handful, you’ll likely realize that compared to modern novels, there was a lot of white space in the margins.
This was commonplace in the days of letterpress printing, and likely a necessity of the process. But even before movable type, when books were completely transcribed, there was quite a wide margin between the end of the text and the end of the page. Interestingly enough, monks would often fill this space up too; not just with text, captions or footnotes, but also with works of art.
Some of the first known markings to be found inside transcribed book margins were old scholion, kind of your ancient-world footnote. They contained translation notes, contextual references and sometimes a scribe’s personal reflections on the text he was working on.
And remember, printing was a much bigger deal before the printing press, so you’ll often find corrections inside the margins of books that date farther back.
Some of these have become extremely important throughout the ages. In an ancient manuscript of Homer’s Iliad, the famous “A scholia” contained commentaries that are, in part, some of the most fundamental sources of information on poems pertaining to the Matter of Rome.
For more modern examples, you should probably turn to Edgar Allen Poe, who’s sometimes attributed to coining “marginalia” as a term. He was also a big proponent of marking up books as a reader…
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