Part 18 (1/2)
The investigations of the writer in this direction, while in soed from them and has been more in the nature of a comparative analytical and microscopic examination of ancient with ancient and modern with modern documents in connection with numerous chemical experiments, the manufacture of hundreds of inks and the study of their time and other phenomena
To accomplish this, ancient documents not written with ”Indian” ink, but with those obviously containing coalls or other tannins, were selected and grouped into color faan with the fourteenth century, continuing well into the nineteenth, to the number of nearly four hundred, each of them of a different date and different year Soible, others less so and by gradual steps they approached to a definite black; many of them as rich and deep in color as if they had been written not centuries ago but within a few years Signatures on the sarees of color, so that the question of thethe appearance of the ink, was not a factor; but the difference in the inks used tofactor
At this point it ations conducted by Mr Swan before referred to and those by the writer and the resultant observations of each 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 tisto New York
assu a second pre of these docuain, the vehicles to hold the particles or possibly preserving substances,to ink formulas was examined to ascertain the naall 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, si those of the aniline family which pertain to the more modern ink co tannin and color-yieldingmaterial Many of the first class have been used in the alls or alone, while but very few of the second class have been used for either purpose
The decoen 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 se 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, h used in the tiallic 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 ti process coo in soment 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 coallate 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 forallate 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 presu the preceding four centuries It has under certain conditions very lasting properties as the yptian allate of iron to retain its black color; on the contrary it seeo for added color was ehteenth century is shown by the for in the literature of that ti before, as well as conteallate of iron fa 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 specireen 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 cliall” inks contained a lasting added color, indigothis line for twenty-three years have already been cited has said that he preferred for his own use an ink coo and copperas (sulphate of iron); this o for ”added” color Like for for different proportions of constituents both before and after his tiland and the continents of Europe and A that its use was more or less constant in this respect To determine, then, whether or not the blacker specio in any of its forms was most important, and the plan adoptedin 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 coave approxiely frohty to five hundred or o was found to be present while inthat the reason for the continuing blackness of the older inks is not due to an added color or pigment of any kind and further ink forinal blackness but deteriorated to a brown color; ive an agreeable and i ink, and to cheapen the cost of manufacture when coallate of iron ink
No disagree 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 urates, quickly absorbs lass) ”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” (Bloxa an undisturbed and co 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 per pristineness can be disturbed only by inferior quality of constituents, wrong methods of admixture and its future environ 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 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 PAPER--ITS METAMORPHOSIS AND AFFINITIES--IGNORANCE OF THE FORGER AS TO ITS ORIGINAL ENVIRONMENT--TREATMENT OF OLD INK MARKS--HOW PAPER MAY DISCOLOR INK--THE USES OF ACID IN INK--VEHICLES TO HOLD INK PARTICLES AND PRESERVE THEM--INKS FIVE CENTURIES OLD DO PRESERVE THEIR GLOSS--SOME CAUSES OF INK DISINTEGRATION--WHEN INK BECOMES IRRESPONSIVE TO THE ELEMENTS-- DEMONSTRATED TRUTHS ABOUT INK CONStitUENTS AND COLOR PHENOMENA--NATURAL EVOLUTION OF AN INK MARK--LENGTH OF TIME REQUIRED TO BECOME BLACK--FIRST INDICATIONS OF AGE--DISAPPEARANCE OF INK QUALITIES--ARTIFICIAL AGING OF INK--TESTS FOR IT AND HOW TO CONFIRM THEM--BLEACHING AND REMOVAL OF INK FROM PAPER CRIMINALLY CONSIDERED-- CHEMISTRY OF SUCH MARKS--THEIR 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 e not only in color but in the case of the iron and gall inks, in their che 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 ele 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 at with that for which it has affinity and instantly beginning with TIME tonatural 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 circuinal ink on paper and that be cannot manufacture the TIME which has already elapsed, it is not strange that attempted fraud can often be iven of the e of tiether on the paper by gue 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 froradually 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 alls or its equivalent in the presence of a weak acid, then if any iron be present, a ree of restoration of color will ensue and reain, the discoloration of an iron ink rades and the bleaching cohly 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 che fluids of this decade carry a superabundance of acid in their coh the paper and ultiallate 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 u the principal one Its purpose is threefold--as before stated, to hold the ink particles in suspension--to prevent the ink fro, 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 specio 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 coloss is invariably loss is present, it was and is because of the elue) 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 coums in their preparation In the course of time these have been absorbed by radual disappearance of their original blackness and gloss and finally a return to the rusty color of oxidized iron
It therefore follows,correct, the older a writing lass is the binder, and which has not been ”blotted,” the harder and more impervious and irresponsive it becoents
The truths demonstrated in this proposition cannot be denied They fortify as certain that a properly proportioned allo-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 che black color more permanent and durable than the substance on which it appears
With a sa fluid, write on ”linen” paper without blotting it; in thirty hours, if exposed to the air and fro should have assu 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 exanification 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 ration and decay is now progressing and when approxie, has destroyed all ink qualities