There has been a discussion lately on the Conservation DistListabout whether books should be rounded and backed, or bound with a flat back by the library binder. The following comment by Per Cullhed in Sweden (
email@example.com) is reprinted here, with his permission, to help put the debate in perspective.
Rounding and backing has always been a subject of controversy, and I think it is impossible to give a conclusive answer to this subject from a technical point of view, but one should be aware of the cultural aspects in book binding.
Rounding and backing (whether by use of a hammer or as a result of tight lacing) came into extensive use during the 16th century with the binding of large books with relatively light paper, wooden boards, tight backs and wide squares. This construction is functional and many of these bindings are still quite sound. The rounding took up the swell from the sewing thread and the backing gave place for the wooden boards which could be laced on tightly. The combination of tight back, rounding and backing ensured that the book block would go back into its original form.
I think that our idea of what a binding is supposed to look like is still influenced by these early books, but we have changed many of the original "ingredients" with sometimes poor results from a technical point of view. One must keep in mind that these "ingredients" constitute a system and this system is changed if we change one or more parts of it.
As for rounding and backing, it can be considered as a sort of pre-set form that stiffens the spine area and makes it more difficult for the fore edge to protrude, but also a means of dealing with the swell of the spine from the thread of a handsewn book. These book blocks will inevitably go either forward or backward when put under pressure in the process of making, or in a bookshelf. Rounding and backing solves this problem. This was an absolute truth until the sewing machines came into use during the late 19th century. This new technique changed the original system because it was possible to produce books with less swell in the spine. The change became even more evident with the double-fan gluing technique when the swell was nearly eliminated. So we have a completely new system that in certain cases can allow us to eliminate both rounding and backing.
The Uppsala University Library began using a flat back technique in the 1960s and this gives an opportunity to study both the rounding and backing system and the flat back system in, for example, serials. My impression is that both techniques work well if they are performed with good craftsmanship. There is one more difference between these binding systems, and that is that the flat back volumes have always been cut flush, i.e., they have no squares. I think this is a major factor for the relative success of our flat back bindings, and I am also certain that the rounded and backed volumes would have survived even better without the squares although they would look uglier and therefore not conform to our idea of what a book should look like.
The binding system has changed so much from the 16th century that the squares have outlived their function as a means of protecting the book block. Many old bindings still stand on parade with the bottom edge perfectly straight 1 cm above the shelf, whereas modern bindings and especially heavy bindings almost always have sunk in their cases with the bottom edge resting on the shelf. I think this is one of the most drastic examples where we have kept a feature which is no longer functional because of other changes in the binding system.
To summarize this subject, I think it is important to be able to judge which binding "ingredients" are the most suited to one's needs and also to be aware of both the cultural and the technical aspects of the chosen binding system.