In 19th century Europe, and all the way up until the 1950s
and 1960s, however, the majority of libraries were managed as a
three-part system consisting of reading rooms, rooms with
catalogues and closed stacks. Users would go to the catalogue room
and search the collection through alphabetical, title or systematic
catalogues and would hand the call number of the desired work to
the counter, waiting for the book to be brought from the closed
stacks. Open access to shelves was only present in reading rooms
for a selected number of reference books and could be found in
smaller academic and public libraries. Closed book stacks with
formal book arrangement according to the size and accession
numbers are still present in almost all old national and university
libraries in Europe. Nowadays these libraries have expanded their
reading rooms and their closed stacks have been extended with
larger open access areas. In closed stacks, to save space, books
continue to be arranged by size and by some other formal principle,
most often an accession number.
It is worth noting that in spite of how it may appear looking
at the library shelves, document classification has always had an
important role in European libraries. Due to differences in
languages and scripts across Europe, classification was often
recognized as the most efficient way of subject access in crossEuropean
information integration. Classification’s main purpose is,
however, that of providing subject access through a systematic
catalogue and many European libraries manage classification of
books for systematic catalogues separately and independently from
call numbering. This may be so even if the entire collection is
arranged systematically. Selection of a class mark for a call number
is ruled by the requirements a class mark has in enabling subject
browsing and although this class mark may be derived from the
complete and detailed classification number representing the book
content it can often be much shorter or even different3