4

a cathedral choir book.
This document, with its antiquated clasp, is number paged,
but at each change in the
service, that leaf has a small
coloured metal clip standing
out beyond the edge (the whole being set
in serrated line), so that the
chorister - remembering the
colour - could open at the
desired music as soon as the organ
struck the first note. see 4A - 4.B-
Intermediate between
the age of M.S.S. and the invention of printing, comes
the Block books, of which this collection has no original.
The most interesting facsimile
being a folio Biblia Pauperum,
from the British Museum