Books always come with blank spaces, which are a vital feature of their visual and typographical design, including the margins and spaces between words and sentences. Sometimes they are intended to be filled in, like the postcard, and sometimes they require the active dismantling of a pre-existing book to create more space for new plates, like the extra-illustrated book. Whether the additions that fill books are ink scribblings, sketched portrait inserts, pasted in engravings, or hand-applied watercoloring, they turn the book into an object altered by its owner’s individual needs, fancies and preoccupations.