One of my last classes at Simmons (now Simmons University) library school was "History of the Book". Lot of latitude there for that professor but it centered on paper, and decorative paper such as marbled end papers. Dripping oil paint onto water and manipulating the designs, then laying down paper.
Long/short the venerable FIELD NOTES have just shone a light on this process in their new release
END PAPERS - good stuff.
The designs were inspired by the
University of Washington Decorated and Decorative Paper Collection
For a primer - and really digestible - grab the Eyewitness reference book to the BOOK.