Bookbinding art is one of the disappearing professions, which is why the bookbinding office at the Provincial and Municipal Public Library is the natural heir to the local craft, which in Bydgoszcz had a large representation, consisting of independent masters and journeymen. When pedestrians stop at 39 Długa Street in Bydgoszcz, curious about the unusual display window on which bookbinding equipment is presented, they do not even suppose that library bookbinders are still working deep inside the room. Inside there are numerous antique machines. Each volume that has gained binding in the bindery has a secret in the form of stamped signatures. It is thanks to them that we know when the book was bound, and from 1931 also who did it, because each bookbinder left a trace in the form of a tiny stamp with its initial. In Bydgoszcz, old books are still restored and give them new life.