As practiced it was pretty much under the control
of the different religious denominations and the information
obtainable about inks from these sources
is but fragmentary. What has come down to us of
this particular era is mostly found on the old written
Hebrew relics, showing that they at least had made
no innovations in respect to the use of their ritualistic
deyo.

The invention of the quill pen in the sixth century
permitted a degree of latitude in writing never before
known, the inks were made thinner and necessarily
were less durable in character. Greater attention was
given to the study and practice of medicine and
alchemy which were limited to the walls of the
cloister and secret places. The monk physicians endeavored
by oral instructions and later by written
ones to communicate their ink-making methods not
only of the black and colored, but of secret or sympathetic
inks, to their younger brethren, that they might
thus be perpetuated. All the traditional and practical
knowledge they possessed was condensed into manuscript
forms; additions from other hands which included
numerous chemical receipts for dyeing caused
them to multiply; so that as occasion required from
time to time, they were bound up together booklike
and then circulated among favored secular individuals,
under the name of "Secreta."