Colorless iodine. Chloride of lime. Brown.

Phenolphtalin. Alkaline solution. Red.

Vanadium. Pyrogallic acid. Purple.

The Patent Office at Washington, D. C., for more than forty years employed a violet copying ink made of logwood. From 1853 until 1878 it was furnished by the Antoines of Paris, of the brand termed "Imperial;" in later years it was supplied by the Fabers.

Since 1896 they have been using "combined" writing fluids.

The following facts elicited by the unrollment of a mummy at Bristol, England, in 1853, were communicated to the Philosophical Magazine, by Dr. Herapath.

He says:

"On three of the bandages were hieroglyphical characters of a dark color, as well defined as if written with a modern pen; where the marking fluid had flowed more copiously than the characters required, the texture of the cloth had become decomposed and small holes had resulted. I have no doubt that the bandages were genuine, and had not been disturbed or unfolded; the color of the marks were so similar to those of the present 'marking ink,' that I was induced to try if they were produced by silver. With the blowpipe I immediately obtained a b.u.t.ton of that metal; the fibre of the linen I proved by the microscope, and by chemical reagents, to be linen; it is therefore certain that the ancient Egyptians were acquainted with the means of dissolving silver, and of applying it as a permanent ink; but what was their solvent?

I know of none that would act on the metal and decompose flax fibre but nitric acid, which we have been told was unknown until discovered by the alchemist in the thirteenth century, which was about 2200 years after the date of this mummy, according as its superscription was read.

"The Yellow color of the fine linen cloths which had not been stained by the embalming materials, I found to be the natural coloring matter of the flax; they therefore did not, if we judge from this specimen, practice bleaching. There were, in some of the bandages near the selvage, some twenty or thirty blue threads; these were dyed by indigo, but the tint was not so deep nor so equal as the work of the modern dyers; the color had been given it in the skein.

"One of the outer bandages was of a reddish color, which dye I found to be vegetable, but could not individualize it; Mr. T. J. Herapath a.n.a.lyzed it for tin and alumina, but could not find any.

The face and internal surfaces of the orbits had been painted white, which pigment I ascertained to be finely powdered chalk."

"I am a scribbled form, drawn with a Pen Upon a Parchment, and against this fire Do I shrink up."

--KING JOHN, v, 7.

"With much ado, his Book before him laid, And Parchment with the smoother side display'd; He takes the Papers, lays 'em down agen, And with unwilling fingers tries his Pen; Some peevish quarrel straight he tries to pick, His Quill writes double, or his Ink's too thick; Infuse more Water; now 'tis grown too thin, It sinks, nor can the characters be seen."

--Persius, translated by Dryden.

INKS CALLED SYMPATHETICAL (Seventeenth Century).

"These operations are liquors of a different nature, which do destroy one another; the first is an infusion of quick-lime and orpin; the second a water turn'd black by means of burned cork; and the third is a vinegar impregnated with saturn.

"Take an ounce of quick-lime, and half an ounce of orpin, powder and mix them, put your mixture into a matra.s.s, and pour upon it five or six ounces of water, that the water may be three fingers breadth above the powder, stop your matra.s.s with cork, wax, and a bladder; set it in digestion in a mild sand heat ten or twelve hours, shaking the matra.s.s from time to time, then let it settle, the liquid becomes clear like common water.

"Burn cork, and quench it in aqua vitae, then dissolve it in a sufficient quant.i.ty of water, wherein you shall have melted a little gumm arabick, in order to make an ink as black as common ink. You must separate the cork that can't dissolve, and if the ink be not black enough, add more cork as before.

"Get the impregnation of saturn made with vinegar, distilled as I have shewn before, or else dissolve so much salt of saturn as a quant.i.ty of water is able to receive: write on paper with a new pen dipt in this liquor, take notice of the place where you writ, and let it dry, nothing at all will appear.

"Write upon the invisible writing with the ink made of burnt cork, and let it dry, that which you have writ will appear as if it had been done with common ink.

"Dip a little cotton in the first liquor made of lime and orpin, but the liquor must be first settled and clear; rub the place you writ upon with this cotton and that which appeared will presently disappear, and that which was not seen will appear.

ANOTHER EXPERIMENT.

Take a book four fingers breadth in bigness, or bigger if you will: write on the first leaf with your impregnation of saturn, or else put a paper that you have writ upon between the leaves; turn to t' other side of the Book, and having observed as near as may be the opposite place to your writing, rub the last leaf of the book with cotton dipt in liquor made of quick- lime and orpin, nay and leave the cotton on the place clap a folded paper presently upon it, and shutting the book quickly, strike upon it with your hand four or five good strokes; then turn the book, and clap it into a press for half a quarter of an hour; take it out and open it, you'll find the place appear black, where you had writ with the invisible ink. The same thing might be done through a wall, if you could provide something to lay on both sides, that might hinder the evaporation of the spirits.

REMARKS.

"These operations are indeed of no use, but because they are somewhat surprizing, I hope the curious will not take it ill, that I make this small digression.

"It is a hard matter to explicate well the effects I have now related, nevertheless I shall endeavour to ill.u.s.trate them a little, without having recourse to sympathy and antipathy, which are general terms, and do not explicate nothing at all; but before I begin, we must remark several things.

"The first is, that it is an essential point to quench the coal of cork in aqua vitae, that the visible ink may become black with it.

"Secondly, that the blackness of this ink does proceed from the fuliginosity or sooty part of the coal of the cork which is exceeding porous and light, and that this fuliginosity is nothing but an oil very much rarefied.

"Thirdly, that the impregnation of saturn, which makes the invisible ink, is only a lead dissolved, and held up imperceptibly in an acid liquor, as I have said, when I spoke of this metal.

"Fourthly, that the first of these liquors in a mixture of the alkali and igneous parts of quick-lime with the sulphureous substance of a.r.s.enick; for the orpin is a sort of a.r.s.enick, as I said before.

"All this being granted, as no body can reasonably think otherwise, I now affirm, that the reason why the visible ink does disappear, when the defacing liquor is rubbed upon it, is that this liquor consisting of an alkali salt, and parts that are oily and penetrating, this mixture does make a kind of soap, which is able to dissolve any fuliginous substance, such as burnt cork, especially when it has been already rarefied and disposed for dissolution by aqua vitae, after the same manner as common soap, which is compounded of oil, and an alkali salt, is able to take away any spots made by grease.

"But it may be demanded, why after the dissolution the blackness does disappear.

"I answer, that the fuliginous parts have been so divided, and locked up in the sulphureous alkali of the liquor, that they are become invisible, and we see every day that very exact solutions do render the thing dissolved imperceptible, and without colour.

"The little alkali salt which is in the burnt cork may also the better serve to joyn with the alkali of the quick-lime, and to help the dissolution.

"As for the invisible ink, it is easy to apprehend how that appears black, when the same liquor, which serves to deface the other, is used upon it. For whereas the impregnation of saturn is only a lead suspended by the edges, of the acid liquor, this lead must needs revive, and resume its black colour, when that which held it rarefied is entirely destroyed; so the alkali of quick- lime being filled with the sulphurs of a.r.s.enick becomes very proper to break and destroy the acids, and to agglutinate together the particles of lead.

It happens that the visible ink does disappear by reason that the parts which did render it black have been dissolved; and the invisible ink does also appear because the dissolved parts have been revived.

"Quick-lime and, orpiment being mixed and digested together in water, do yield a smell much like that which happens when common sulphur is boiled in a lixivium, of tartar. This here is the stronger, because the sulphur of a.r.s.enick is loaded with certain salts that make a stronger impression on the smell. Quick- lime is an alkali that operates in this much like the salt of tartar in the other operation; you must not leave the matra.s.s open, because the force of this water doth consist in a volatile.

"The lime retains the more fixt part of the a.r.s.enick and the sulphurs that come forth are so much the more subtile, as they are separated from what did fix them before, and this appears to be so, because the sulphurs must of necessity pa.s.s through all the book to make a writing of a clear and invisible liquor appear black and visible: and to facilitate this penetration the book is strook, and then turned about, because the spirit or volatile sulphurs do always tend upwards; you must likewise clap it into a press, that these sulphurs may not be dispersed in the air. I have found, if that these circ.u.mstances are not observed, the business fails.

Furthermore that which persuades me that the sulphurs do pa.s.s through the book, and not take a circuit to slip in by the sides, as many do imagine, is that after the book is taken out of the press, all the inside is found to be scented with the smell of this liquor.

"There is one thing more to be observed, which is, that the infusion of quick-lime and orpin be newly made, because otherwise it will not have force enough to penetrate. The three liquors should be made in different places too; for if they should approach near one another, they would be spoiled.

"This last effect does likewise proceed from the defacing liquor; for because upon the digestion of quick- lime and orpin, it is a thing impossible for some of the particles will exalt, stop the vessel as close as you will; the air impregnated with these little bodies does mix with, and alter the inks, insomuch that the visible ink does thereby become the less black, and the invisible ink does also acquire a little blackness."

Priceless MSS. in immense number written in periods between the third and thirteenth centuries have been destroyed by modern scholars in experimentations based on the false theory that the faded inks on them, whether above or below other inks (palimpsests), contained iron.

Sulphocyanide of pota.s.sium is highly esteemed as a reagent for the restoration of writing, if iron is present.

Theoretically, it is one of the best for such a purpose if employed with acetic acid. It causes, however, such a decided contraction of parchment as to be utterly useless, but for paper MSS. is excellent. The metallic sulphides generally p.r.o.nounced harmless, causes the writing to soften and become illegible in a short time. On the other hand, yellow prussiate of potash, with acetic acid in successive operations is of great service in treating the most perplexing palimpsests.

Ink which badly corrodes a steel pen need not necessarily be condemned; it may contain just the qualities which make it bind to the paper and render it more durable.

Some inks which are fairly permanent against time if not tampered with, can be removed with water.

This is true of the most lasting of inks,--the old "Indian."

In ancient Latin MSS. the words fuco, fucosus and fucus are found to be frequently employed. It is interesting to note the variations in their meaning:

FUCO.--To color, paint or dye a red color.

FUCOSUS.--Colored, counterfeit, spurious, painted, etc.

FUCUS.--Rock lichen (orchil) red dye. Red or purple color. The (reddish) juice with which bees stop up the entrance to their hives. Bee glue.

FUCUS.--A drone.

In j.a.pan the word "ink" possesses more than one meaning Four hundred Inks--one degree of sixty miles." (See Geographical Grammar, of 1737, page 3.)