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were substantially alike。 Many of the writer's; however;

preceded those of Mr。 Swan's; for during the

years 1885 and 1886; having had the custody of part

of the Archives of the City of New York there were

many opportunities to study this subject which were

taken advantage of; before and after which time

frequent examinations were made of writings much

more ancient than those pertaining to New York。



Assuming a second premise was to assert that the

inks employed in the writing of these documents

were 〃straight〃 or possessed some 〃added〃 pigment

or color。 Again; the vehicles to hold the particles or

possibly preserving substances; might be factors。



All literature possible referring to ink formulas

was examined to ascertain the names of materials

recommended or formerly 〃added〃 to gall inks; because

if the pristineness of the blacker inks was due

to the added pigment it was a safe proposition that it

was still existent in the ink; and that if it could be

discovered part at least of the problem would be;

simplified。



The 〃added〃 color compounds; excluding those of

the aniline family which pertain to the more modern

ink compositions; are of two classes: those possessing

tannin and color…yielding materials and those containing

only a color…yielding material。 Many of the first

class have been used in the manufacture of ink both

with infusions of nut…galls or alone; while but very

few of the second class have been used for either purpose。

The decomposing action of light; oxygen and

moisture on many of each class placed them beyond

the purview of consideration; while the dates of the

discovery and the fact of the small percentage of tannin

contained in others permitted them also to be

discarded。 For instance: vanadium; which is fairly

permanent; was discovered only in 1830; chanchi; the

ink plant of New Granada discovered in the sixteenth

century; possessing excellent lasting qualities; does not

assimilate perfectly with other constituents used in the

manufacture of ink; but is best when used alone;

Berlin blue (prussian blue) is well spoken of; but

was only discovered by accident in 1710 by Diesbach;

a preparer of colors at Berlin; logwood; more used

for this purpose than any other material; was first

imported into Europe in the sixteenth century and

causes a deterioration of the durable qualities of the

tanno…gallate of iron; Brazil…wood and archil; and

their allies; are exceedingly fugitive; bablah; the

fruit of the acacia arabica; myrabolams; of Chinese

growth; catechu; and sumac which though used in

the time of Pliny; each contains a percentage of

gallic acid too small to meet the requirements。

Divi…divi; a South American product; came into use

only at the end of the sixteenth century and has not

stood the test of time。



This sifting process completely eliminated all but

lampblack; madder and indigo in some form as a

permanent 〃added〃 color pigment。 Lampblack;

which is we know forms the basis of 〃Indian〃 ink;

is not soluble and requires a very heavy gummy

vehicle to prevent its immediate precipitation; and

while it could have been used in combination with

tanno…gallate of iron as an ink; the fact that it was

possible to chemically remove the ancient inks which

remained black; was a sufficient demonstration that

this carbon substance; which is not affected by chemicals;

either as contained in the fluid ink or as dusted

on after writing; could have formed no part of the

ancient tanno…gallate of iron inks。



Madder is mentioned as of very ancient times and

was cultivated in Europe as early as the tenth century;

its addition to an iron and gall ink is said to be

an invention of the year 1855; it is certain; however;

that it was used for a like purpose as early as 1826;

and a fair presumption that it was frequently

employed in some form during the preceding four

centuries。 It has under certain conditions very lasting

properties as the madder…dyed cloths found

wrapped around Egyptian mummies demonstrates;

but does not assist the tanno…gallate of iron to retain

its black color; on the contrary it seems to lessen this

quality。



That indigo for added color was employed by ink

manufacturers in the eighteenth century is shown by

the formulas appearing in the literature of that time。

It was used alone as an ink long before; as well as

contemporaneously with; those of the tanno…gallate of

iron family。 Its lasting properties are most remarkable

if it be true that; used as a dye; there is still in

existence specimens of it on cloth five thousand or

more years old。 The history of its use ALONE as an

ink is difficult to ascertain back of a certain period;

the writer has several specimens of it; one written in

1692 whose color is a green blue; another written

about a century ago is believed to be as bright blue

as the day it was placed on the paper; from 1810 to

1850 it was in common use particularly in hot

climates where it was 〃home…made。〃 Consequently

if the old 〃gall〃 inks contained a lasting added

color; indigo must have been the one; Dr。 Stark

whose investigations along this line for twenty…three

years have already been cited has said that he

preferred for his own use an ink composed of galls;

sulphate of indigo and copperas (sulphate of iron);

this means a tanno…gallate of iron ink with indigo for

〃added〃 color。 Like formulas calling for different

proportions of constituents both before and after his

time in England and the continents of Europe and

America are to be found in considerable number;

proving that its use was more or less constant in this

respect。 To determine; then; whether or not the

blacker specimens of the ancient writings contained

indigo in any of its forms was most important; and

the plan adopted most simple。 Specimens of writing

in ink of which the manufacturer's name was known

as well as his formula and only thirty years old

showed evidence of considerable 〃browning;〃 some

of them when tested in juxtaposition with those of

from fifty to one hundred years old which had turned

completely brown; gave approximately the same results;

and differentiated largely from the results obtained

from jet black specimens of eighty to five

hundred or more years of age。 In a number of the

browner ones indigo was found to be present while in

many of the black ones it was not; demonstrating

that the reason for the continuing blackness of the

older inks is not due to an added color or pigment of

any kind and furthermore that the 〃Stark〃 and

corresponding ink formulas after the test of TIME did not

retain their original blackness but deteriorated to a

brown color; moreover; that their purpose as in the

present day was to give an agreeable and immediate

color result; a free…flowing ink; and to cheapen the

cost of manufacture when compared with that of an

unadulterated tanno…gallate of iron ink。



No disagreement being now possible as to the lasting

color virtues of a properly proportioned tanno…

gallate of iron ink WITHOUT an 〃added〃 color or

pigment; there remained the sole question as to the

vehicle utilized to hold this combination in suspension

and whether or not it had to do with the continuing

blackness of the older inks。



The answer must lie between the vegetable product

known as gum and the animal product known as

gelatine。 The first disintegrates; quickly absorbs

moisture and gradually disappears; while gelatine

(isinglass) 〃contains under conditions 50% carbon;

although its molecular formula has not yet been

determined。 It cannot be converted into vapor and

does not form well…defined compounds with other

bodies; it is insoluble in alcohol which precipitates it

in flakes from its aqueous solution。 It is also precipitated

by tannin; which combines with it to form

an insoluble non…putrescible compound。 Gallic acid;

however; does not precipitate it。〃 (Bloxam。)



Possessing an undisturbed and complete history it

was the very substance employed long before the discovery

of gall ink; and is found present in the earliest

specimens of the 〃Indian〃 inks which remain to us。



It must now be evident that there can be no material

difference of opinions as to what has been so

clearly and conclusively established; viz。 that ink

which contains a base of tanno…gallate of iron (without

〃added〃 color) is a permanent ink; and the

length of its durability and continuing pristineness

can be disturbed only by inferior quality of constituents;

wrong methods of admixture and its future

environment。 Hence any black ink with this combination

missing is of no practical value whatever

either for record or commercial uses。



〃Indian〃 ink; except for specific purposes; belongs

to the great past and will so continue with its

virtues unchallenged and proven; until some solvent

is discovered for the carbon which forms nearly the

whole of

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