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is discovered for the carbon which forms nearly the
whole of its composition； at which time THE perfect
ink can be said to have been discovered。
CHAPTER XVII。
INK PHENOMENA。
CONDITION OF INK WHEN FIRST PLACED ON PAPERITS
METAMORPHOSIS AND AFFINITIESIGNORANCE OF THE
FORGER AS TO ITS ORIGINAL ENVIRONMENTTREATMENT
OF OLD INK MARKSHOW PAPER MAY DISCOLOR
INKTHE USES OF ACID IN INKVEHICLES
TO HOLD INK PARTICLES AND PRESERVE THEMINKS
FIVE CENTURIES OLD DO PRESERVE THEIR
GLOSSSOME CAUSES OF INK DISINTEGRATIONWHEN
INK BECOMES IRRESPONSIVE TO THE ELEMENTS
DEMONSTRATED TRUTHS ABOUT INK CONSTITUENTS AND
COLOR PHENOMENANATURAL EVOLUTION OF AN
INK MARKLENGTH OF TIME REQUIRED TO BECOME
BLACKFIRST INDICATIONS OF AGEDISAPPEARANCE
OF INK QUALITIESARTIFICIAL AGING OF INKTESTS
FOR IT AND HOW TO CONFIRM THEMBLEACHING AND
REMOVAL OF INK FROM PAPER CRIMINALLY CONSIDERED
CHEMISTRY OF SUCH MARKSTHEIR RESTORATION
VARIATIONS IN METHODS WHICH CAN BE
EMPLOYED。
ALL inks when first placed on paper are of course
in a fluid state。 Gradual evaporation of moisture
causes a change not only in color but in the case of
the iron and gall inks； in their chemical constitution；
being immediately affected by their environment；
whether due to the character of the paper on which
they rest； the kind or condition of the pen used； or
most important of all； the elements。 Those who use the
black inks and chemical writing fluids will have noticed
these characteristics。 The pale brown； blue or green
as first written； and the gradual change after a short
period to an approaching blackness； are reactions due
largely to atmospheric conditions； the oxygen uniting
with that for which it has affinity and instantly
beginning with TIME to make its march； producing
natural phenomena； which can be only superficially
imitated but never exactly reproduced。 When we
further take into consideration that the forger cannot
always know of the circumstances which surround
the placing of original ink on paper and that be cannot
manufacture the TIME which has already elapsed；
it is not strange that attempted fraud can often be
made evident and complete demonstrations given of
the methods employed。
With the passage of time； the particles in some
inks which are held together on the paper by gummy
vehicles； commence to disintegrate and change from
intense black to the brown color of iron rust； the
〃added〃 color which of itself is fugitive in character；
soon departs； the vegetable astringent separating
from the iron salt decays gradually and disappears
and finally terminates in a mere stain or dust mark
which can be blown off the paper。 Sometimes； the
written surface of such paper can be treated by carefully
moistening it with a decoction of nut…galls or its
equivalent in the presence of a weak acid； then if any
iron be present； a measurable degree of restoration of
color will ensue and remain for a short period。
Again； the discoloration of an iron ink may be due to
the character of the paper； if of the cheaper grades
and the bleaching compounds employed in their
manufacture are not thoroughly washed out； then the
ink not only begins to absorb oxygen from the
atmosphere but the chlorine in the paper attacks it
and the process of destruction is thereby hastened。
The introduction of acid into ink has two purposes；
one to secure more limpidity； and the other to cause
it to penetrate the paper and in this way bind
together the constituent particles of both ink and
paper。 Most of the chemical writing fluids of this
decade carry a superabundance of acid in their
composition； which in time will burn through the paper
and ultimately destroy it。
All tanno…gallate of iron inks require some vehicle
to hold their particles in a state of suspension； otherwise
there would be precipitation and such an ink
could not be used。 To meet this requirement a
variety of gums are employed by manufacturers；
gum acacia being the principal one。 Its purpose is
threefoldas before stated； to hold the ink particles
in suspensionto prevent the ink from flowing too
rapidly； and after drying WITHOUT blotting； to act as
an envelope to encase the now fixed ink and prevent
or interfere with its absorption of an excess of oxygen。
The longer these latter conditions obtain the longer
will the ink retain its pristineness； its durability and
permanence。 The 〃time proved〃 ink…written specimens
of five hundred years or more ago which continue
to retain their original intense black color and
〃glossy〃 appearance； do not； however； yield any evidence
of the use of vegetable gums in their composition。
Where such instances have been noticed the gloss is
invariably missing。 But； where ANY gloss is present；
it was and is because of the employment of isinglass
（fish…glue） as the vehicle to hold the ancient ink
particles。
Hence the variations of color seen in ancient paper
writings； as already stated； were due not only to possible
imperfect admixtures of the component parts of
the inks； but to the use of vegetable gums in their
preparation。 In the course of time these have been
absorbed by moisture which hastened disintegration；
causing a gradual disappearance of their original blackness
and gloss and finally a return to the rusty color
of oxidized iron。
It therefore follows； my observations and deductions
being correct； the older a writing made with
tanno…gallate of iron ink； where isinglass is the binder；
and which has not been 〃blotted；〃 the harder and
more impervious and irresponsive it becomes to the
action of the natural elements or of chemical reagents。
The truths demonstrated in this proposition cannot
be denied。 They fortify as certain that a properly
proportioned mixture in water of an infusion of nut…
galls or gallo…tannic acid and sulphate of iron； with
isinglass as the vehicle to bold the particles in a state
of suspension； if written with on good paper and allowed
to dry without blotting； in a short time becomes
encased or enveloped in such vehicle； which is thereby
rendered substantially insoluble and absolutely
prevents any extensive oxidation。 Also； as a further
consequent result； there is chemically created an
unchangeable and continuing black color more permanent
and durable than the substance on which it appears。
With a sample of standard commercial chemical
writing fluid； write on 〃linen〃 paper without blotting
it； in thirty hours； if exposed to the air and
from three to five days if kept from it； the writing
should have assumed a color bordering on black； it
becomes black at the end of a month under any conditions；
and so continues for a period of about five
or six years； when if examined under a lens of the
magnification of ten diameters； there will be a noticeable
discoloration of the sides or pen tracks which
slowly spreads during a continuing period of from ten
to fifteen years； until the entire pen marks are of a
rusty brown tint。 A species of disintegration and
decay is now progressing and when approximately
forty years of age； has destroyed all ink qualities。
If； however； 〃chemical writing fluid〃 is first treated
by exposure to the fumes of an ammoniacal gas； a
〃browning〃 of the ink occurs； not only of the pen
tracks but of the entire ink mark。 If examined now
with a lens； the ink is found to be thin enough to permit
the fibre of the paper to be seen through it； thus indicating
artificial age。 Furthermore； if a 20 per cent
strength of hydrochloric acid be applied； the 〃added〃
color （usually a blue one） is restored to ITS original
hue； alike experiment on 〃time〃 aged ink gives
only the yellow brown tint of pure gall and iron
combinations； the 〃added〃 color having departed caused
by its fugitive characteristics。 Again； if a solution of
chlorinate of lime or soda be applied； the ink mark
is instantly bleached； where in the case of honest old
ink marks； it takes considerable time to even approximate
a like result。
To confirm the chemical tests which may be employed
in the determination of the artificial aging of
ink marks； photographs made by permitting light to
transmit through the paper and to interfere with its
rays by filtering them through a 〃color〃 screen containing
orange and some green； will indicate the presence
of a fugitive substance in the ink； usually the
〃added〃 color employed in its manufacture。
The process of bleaching or 〃removal〃 of ink marks
from paper is frequently employed in the attempted
eradication of words or figures and the substitution
of others on monetary instruments； commonly called
〃raising。〃 Its purpose is usually a criminal one and
some observations as to the modus operandi and its
chemistry are not out of place here。
Ink marks made with a compound consisting of the
combination of iron and an infusion of galls or its