As you look at this remember that it is a functional working machine that has a family history of hundreds of years. The earliest scrolls written on papyrus or animal skins used wood as a core to keep the writings in order. When the scrolls were replaced by the early hand made books the skins or parchment was trimmed into large areas for the scribe to record the word, These were the tied and then sewn together. Putting a sheet of wood over the pile of "pages" made the sewing and trimming of the early book that bit easier. When paper came to use and hand writing was replaced by block printing and then movable type. Yet the pages or blocks of pages still had to be held for the binding process and many "Book Presses" were made for this purpose. In more recent times the Libraries of the great houses took pride in keeping their rare and old books but a standing book can in time warp whatever it is made from. A book press, like this one were standard equipment then and still will help preserve a book by presenting an overall even pressure which prevents the natural grain in the paper from curling.