of binding and sewing several quires or gatherings in order to form a volume.
It was the last operation the codex underwent,
with which it was already complete.
The function of bookbinding is not only keeping
all gatherings bound together and in the correct order,
but also to protect them,
and it could confer decoration and luxury to the codex as well.
Although, as a matter of fact,
we know that some books were circulated just being sewn,
without any boards or cover.
Not many medieval bookbindings have been preserved,
in part because the sole use of the book can end up breaking the bonds,
and then a rebinding becomes necessary,
but also because many of the great collectors and
bibliophiles liked to have all their books bound similarly,
and as a consequence they had too many codices rebound.
And, what is most appalling, until relatively recently,
manuscript restoration didn't give much attention to book bindings,
and many of them were separated from their original text-block,
and even discarded and thrown away.
The study of bookbinding,
at least from a codicological point of view is
no older than the middle decades of the 20th century.
Before that only lavishly decorated bookbindings received attention,
and only from an artistic point of view,
as one of the minor arts; and therefore,
only decoration of the covers was taken into consideration.
Nowadays, things have changed and the codicological modus operandi
is reconstructing the technical process that was followed in each period.
Here we meet our curious situation: the best moment to study the binding of
a book is when it is deteriorated and its structural elements are visible,
since when a bookbinding is in a perfect state, these remain hidden.
Actually, the ideal moment to study a bookbinding is when
the manuscript is dismounted for restoration,
but it is extraordinarily unusual that
libraries give researchers access to the restoration labs,
and therefore in practice this possibility remains reserved to
the restorers and the curators of the libraries.
In the remaining minutes of this video,
we shall see the parts of a bookbinding and the elements that each of the parts
has.This is necessary because the description
of a bookbinding uses a highly controlled vocabulary,
which we need to know.
For the following video,
we leave a general view of the evolution of bookbinding techniques.
When considering bookbinding, we distinguish
three fundamental parts: the text-block or book-block, boards, and cover.
The text-block is the set of quires or gatherings that form the volume,
already in their correct order.
The most common method of keeping the gatherings
together is sewing them with twine thread or a fine cord.
The sewing thread goes through the centerfold of each of the quires,
binding it to the preceding and following quire.
The side of the text-block that has received the sewing is called
spine and the rest of the sides, edges.
In order to sew the gatherings together,
they are usually preferred by means of small holes in
their precise places where the sewing thread will go through.
The normal procedure is cutting these holes on the centerfolds of the quires,
but it is also possible,
especially when binding loose leaves,
that the sewing happens on the inner margin, near the fold,
in which case it is called the stabbing or side-sewing,
in its modalities of saddle-stitch and overcasting or oversewing.
As said, the most common method was passing
the sewing thread through the holes pre-made on the folds of the gathering,
and from fold to fold the thread runs inside the gathering,
in parallel to the fold.
There are two techniques of sewing the quires: link-stitch and sewing supports.
Link-stitch is the oldest technique.
It consists on linking each quire to the preceding one by
means of a loop that goes behind the sewing thread of the previous quire,
as shown in the figure.
There are two possibilities.
The first and most common one is using
a single thread that moves along the quire centerfold, chain-sewing with one thread,
or two different threads,
in which case the thread moves only between two contiguous sewing stations,
as shown in the image.
This last technique mustn’t be mistaken for a similar one,
in which two threads are also used,
but they cross each other between the pair of sewing stations.
Link-stitch provides a very solid union
among the different quires but is not devoid of disadvantages.
To start with, with the frequent use of the book,
the spine tends to deform and adopt a concave shape,
apart from the fact that the sewing thread is not a strong
enough to support the weight of the wooden boards.
But the main inconvenience is that the pressure caused by
the opening of the book can end up tearing the stitching.
These inconveniences were solved by
means of other technique utilized to keep the gatherings together,
which is the sewing supports.
The term sewing supports is applied to the ropes or leather thongs
that run perpendicular to the quires coinciding with the sewing stations.
Then the sewing thread leaves the interior of the gathering through the sewing station,
moves around the sewing support,
and returns to the gathering through the same hole it had left.
Sewing supports can be simple or double.