In the old days books were sometimes illustrated, and sometimes had these header and footer drawings as well. These sometimes looked like quick sketches from artists, but had a lovely presentation on the theme from the book. Like these ones I ran into today, from the book Satyres et Flagellants (artwork for this book can be found on Vintage Fetish Art)

Artist for these sketches I am not sure about, the book was illustrated by Gaston Smit