Book XVI, chapters 8–13: Secret and undiscovered notes

CHAP. VIII.

How Messengers may be sent, who shall neither know that they carry letters, nor can they be found about them.

OUr Ancestors had another Art, that could not be discovered, invented by strange craft. Herodotus mentions it from Hestiaeus, who was the Author of it. He being born in Asia, when of noble place, when Darius ruled, when he was with the King in Persia, and would privately write to Aristagorus to fall from him, fearing lest if he should not do it cunningly, he should be discovered, and be in great danger, he invented this way. He shaved off his servants hair of his head, as though he meant to cure him, who for a long time had been troubled with […] eyes: and on his head, with good ink, he writ letters, that contained what he meant to have done, he kept this fellow at home with him, until his hair was grown again; when that was done, he sent him away to Aristagoras, bidding him say, when he came to him, that he should do unto him, in shaving off his hair, as he did before: When the servant came to Aristagoras, to Mile[…]um, he said what his Master bad him say to Aristagoras: he supposing the bu[…]ne[…]s not to be idle, did what he was ordered, and so read the message. The Antients found out these inventions, to send messengers with. Yet that can be no safe way, to shave off the hair, and to write letters upon the head, for the head will easily sweat, and put them out. And if the skin be pricked with a needle, this will not avoid the suspition, if he that wears the writing, be laid bold on by the way: for then is there most diligent search: for fear and necessity will make men watchful, and they are never satisfied, till they have searched every place. Sometimes they try men by fair promises, sometimes they fright them with threats; and if these will not do, they torment and torture them, to make them confess: and if this will not do, that letters may not be secretly conveyed, not onely their hose and shooes use to be searched, their clothes pluckt off, and the seams riot, but they will search their very guts; so far is it from keeping any secret upon the head, that shall not be look'd for. But I can send Letters, and write so, that it can be understood by none, but those that the letters are design'd for. And he that carrieth them never so far off, if he should be taken by the way, and examined by torments, he can confess nothing, because he knows nothing of it, and the Letter shall always remain secret. Nor will length of time, or sweat in travel, blot out the Letters; nor is it any matter if the messenger pass through Rivers, Seas, or Rain; for wet will not hurt them. What good Princes may get by this, I leave to your cogitations; for they have most need of this, when they would declare any thing to their friends, that are besieged: and oft-times upon one message, may the victory of a City or Army depend. The invention of the Antients, was partly good, and partly bad. They writ Letters on his head, which he could not read; nor would water or sweat, wash them off, because they were printed into the head: and when the hair grew out, they could not be seen. And that the messenger might be ignorant what was writ upon his head, they took occasion for it, saying, he had a pain in his eyes, that they would cure: and thus he knew not the craft they used. But this fraud seems not very secure, for one that should suspect it might shave off the hair, and find out the secret. Moreover, if the messenger were to be sent suddenly, how could he stay a moneth, till his hair were grown again? and when his skin was prickt for to make the Letters, he must needs suspect something. But let us see

How Hestiaus could make the Letters on his head indelible.

He wounded the skin with the point of a needle, or opened it with a rasor, and cast in the powder of Colophonia burnt; for so we use to make the names of Masters, upon the faces of bond-slaves, that they shall never come forth, and in time they will look green. Also

Letters may be made between the skin, that are indelible, upon any part.

You may soon do it thus: Let Cantharides steep a whole day in strong water, but sooner is it done in water of separation; then make the letters with a Pen-knife, or fit instrument, upon the upper skin of the Arm, or any other part; the flesh hurt with the moysture, will rise in blisters, and be exulcerated; so by the force of this corroding water, will there always remain the prints of white letters, and they will never be blotted out. And this is best done by Hestiaus secret, because the letters could not be read under the hair, whereas white letters, like milk, would be seen. But would we have them stay onely for sometime, and not always, we may do it many ways. If you make letters with Aqua fortis, that hath eaten silver or brass, they will appear many days. So it may be done with oyl of Honey. Now I will shew

How a man may carry letters that are indelible and invisible, and unknown to him; and how to make them visible when need is.

You may do it thus: by writing letters on the messengers back, that he may not know of, having first given him an Opiat to make him sleep soundly, then write, and let them dry in; when he awakes, send him away, the letters dried on will not be seen: The Antients knew this. Ovid saith it:

Write on his back for paper, so you shall
Better conceal your purpose from them all.

But let us see whether we can write on the flesh with any liquour, that passing through Rivers and Rain, the letters may not be blotted out with any moysture, and then by strewing on of dust, may be made visible again. Write on a mans back, which shall be visible onely, by being wet with some humour, and no man can find out, unless he know the secret. If you write with water, wherein Vitriol is dissolved, with a decoction of Galls, it will be seen. If it be made very sharp, it will pierce the skin, and the letters will be delible: we may do the same with the oyl of it. Salt Ammoniac with quick Lime, or Sope, will make a blew colour. If they be rubbed with oyl of Litharge, they will appear white, with Aqua vitae, or its equal, distilled vinegar, and water and Salt.

CHAP. IX.

How Characters may be made, that at set days shall vanish from the paper.

I Shall attempt to shew how letters may be written on paper, or in other matter, that shall disappear at set times: and other letters shall be made invisible, that at a time certain shall appear, not onely useful for secret marks, but for other purposes necessary for our lives. Letters that decay and vanish, may be made two ways, either with Aqua fortis, that eats the paper, or some decaying liquors, that will vanish with any light touch, and leave the place where they were, without any spot. I shall teach

How letters are made, that eat the paper.

If you mingle oyl of Vitriol with common ink or any other black colour, in few days by corroding the paper, or the ink it self, the letters will vanish, or in a moneth, as you put in more or less of the oyl; and this you may try before you send away your letter: If you would have it work more slowly, add but a little oyl; if faster, put in more: you may, when it is too strong, put some water to it. The same is performed, if you mix a strong lye, they call it the Capital, with your ink; for first they will be yellow, and then they will vanish. The same is done by oyl of Tartar, or Salt Alkali, or Soda, and strong water of separation of Gold; for these corrode the letters, and the paper, that nothing of the letters will appear. If you desire to know

How letters may be made, that will soon vanish;

Make them with the strongest Aqua vitae, or use Camphir and burnt straws: for the letters in time, will decay and vanish; the tincture will fall off, when the glutinous matter is gone. Make a powder of a very fine touch-stone; for the Sandy-stone will sooner decay, that no letter shall be seen. Also it is done

Another way:

Infuse the small filings of steel in water of separation; take a treble quantity of this, and add thereto liquid Pitch, or Soot of Turpentine, to make it the blacker, and cover the vessel: grind this on a Porphyre-stone, write, and they will vanish and fall away. This secret I thought not fit to overpass, because it is the principal thing to be considered, to make tryal oft-times; for if it stay long on the paper, add more strong water to it; and if you be careful, no mark of the writing will remain. You shall do it like to this, another way. If it be good so to counterfeit: Take Chrysocolla, Salt Ammoniac, and Alom, all alike; powder them all, and put them into a Crucible, and make a strong lye of quick-lime, and laying a linnen cloth over the mouth of the vessel, that must receive it, strain it; boil it a little, mingle this with your ink, they will remain a while, but in short time the letters will vanish away. Set it up for you use. But contrarily, if you will

That invisible letters after some time, shall become visible

and shew themselves; I will give you some examples, that you may invent more thereby your self. If you write with juice of Citrons or Oranges, on Copper or Brass, and leave this so for twenty days, the letters will appear green upon the place: the same may be done many other ways, namely, by dissolving salt Ammoniac in water, and writing with it upon Brass, the place will sooner appear of verdigreese-colour.

CHAP. X.

How we may take off letters that are written upon the paper.

IF we would take letters from off the paper, or that such as are blotted out might appear again, we must use this art. As, if we would

Take letters off the paper,

or from parchment: Take Aqua fortis, that is it that parts gold from silver: with a pensil wipe some of this upon the letters, it will presently wipe off letters, written with Gall and Copras. If you use Aqua fortis, wherein salt Ammoniac is dissolved, it will be sooner done. But printed letters are harder taken out, because that ink hath neither Galls nor Copras: Or rub it with salt Alkali and Sulphur, making little balls of them, and that will eat them out, that nothing shall be seen. But if you desire to write any thing in the place you have made clean; first, wet the place with water, wherein Alom is dissolved, for the ink will not run about. If you desire

To renew letters decayed,

or to read such as are vanished: Boil Galls in wine, and with a spunge wipe over the letters, the letters will presently be seen, when they are once wet thus, and be well coloured as they were at first.

CHAP. XI.

How to counterfeit a seal and writing.

IT may be of great use when places are besieged, and in Armies, and affairs of great men, to know how to open letters, that are sealed with the Generals Seal, and signed with his Name, to know what is contained within, and to seal them again, writing others that are contrary to them, and the like. I will shew how

To counterfeit the Seal.

Melt Sulphur, and cast it into powder of Ceruss, while it is melted; put this mixture upon the Seal, but sence it about with paper or wax, or chalk, and press it down; when it is cold, take it off, and in that shall you have the print of the Seal. I will do it another way. Fill an earthen pot with Vinegar, cast Vitriol into it, and a good deal of Verdigreese; let it bubble on the fire, put plates of iron into it; after a short time take them out, and from the out-side with your knife, scrape off a kind of rust it hath contracted, that is durty as it were, and put this into a dish under it: again, put them into the earthen pot, and scrape more off when you take them out; do this so often, till you have some quantity of this durty substance: cast quick-silver into this, and make a mixture; and while it is soft and tender, lay it on the Seal, and press it down, and let it remain in the open Air, for it will grow so hard, that you may almost seal with it; for it will become even like to a Metal. It may be also done another way: Take the filings of steel, and put them in an earthen Crucible at a strong fire; put such things to it, as will hasten the melting of it: when it is melted, cast it into some hollow place, pownd it in a brass Mortar, for it will be easily done: do it so three or four times; then powder it, and mingle quick-silver with it, and let it boil in a glazed vessel six hours, till it be well mingled; then press the seal upon it, and let it cool, and it will become exceeding hard. It is possible

To make a great Seal less,

if it should happen that we want a lesser seal, we must do thus: Take Isinglass, and dissolve it in water: anoynt the figure with oyl, that it may not stick to the glew; compass the seal about with wax, that the matter run not about; put the Isinglass to the fire, and melt it, pour it upon the seal; after three hours, when it is cold, take it away, and let it dry, for the seal when it is dry, will be drawn less equally. If you will

Imitate the form of a writing,

do thus: Open the letter upon a looking-glass, that wants the foyl: upon the letter lay white paper, and a light under the glass; temper your ink as the writing is, and draw your lines upon the lines of the letters you see through. We may

Open letters, and shut them without suspition.

We use to seal letters, putting paper upon them, which goes through the letter on one side, and wax is put on the other side, where it comes forth, and there it is sealed. You shall open the letter thus: Break away that part of the paper, that is put upon the place, where it passeth through the letter, and the hole is, the letter opens presently: read it, and shut it again, and put the paper torn off, in its proper place: first, anoynting the crack with gum-traganth, dissolved in water; for the paper will be so glewed, that it will be stronger there then elsewhere; press it with a small weight, till it grow dry; the fraud cannot be discovered, because the glew is white, and is not known from the colour of the paper.

CHAP. XII.

How you may sp[…]ak at a great distance.

THere are many way how we may speak at a very great distance, with our friends that are absent, or when they are in prison, or shut up in Cities; and this is done with safety, and without any suspition, as I shall shew. Two things are declared here, either to do it by open voice re[…]uplicated, or else by a Trunk. We may

With open voyce shew some things to those that are confederate with us.

It is wonderful, that as the Light, so the Voyce is reverberated with equal Angles. I shall shew how this may be done by a glass. It is almost grown common, how to speak through right or circular walls. The voice passing from the mouth goes through the Air: if it goes about a wall that is uniform, it passeth uncorrupted; but if it be at liberty, it is beaten back by the wall it meets with in the way, and is heard, as we see in an Eccho. I through a circular building, that was very long and smooth, spake words to my friend, that heard them round the wall, and the words came entire to his ears; but one standing in the middle heard not any noise, and yet I heard again what my friend answered to me. In the morning whenas I walked by the sea shore, I heard above a mile, what my friends talked in a Boat: the sea was very calm, and scarce moved, and the words came clearly to me, carried on the plain superficies of the water. I hear that at Mantua, and other places, a great Gallery is built, wherein one speaking in the corner, is heard by another that knows the business, standing in another corner; but those that stand in the middle, perceive nothing of it. But more exactly and clearly

To signifie to friends all things by a Trunk,

Let the pipe be of Earth (but lead is better) or of any matter well closed, that the voice may not get forth in the long passage; for whatever you speak at one end, the voice without any difference, as it came forth of the speakers mouth, comes so to the ears of him that hearkneth; and I doubt not but this may be done some miles off. The voyce not divided or scattered, goes whole a long way I have tried it for above two hundred paces, when I had no other convenience, and the words were heard so clear, and open, as the speaker uttered them: Upon this it came into my mind, to intercept words spoken by the way, with leaden pipes, and to hold them so long as I pleased close in; that when I opened the hole, the words should break forth, I perceive that the sound goes by degrees, and that being carried through a pipe, it may be shut up in the middle; and if a very long Trunk should take away the convenience of it, that many winding pipes might shut it up in a close place. I read that Albertus made an Artificial head, that spake at a set time: I might hope to do the same by this invention; yet I never tried this farther then I have said: yet I have heard by my friends, that lovers have spoke a long time through a leaden pipe, from their Houses that stood far asunder.

CHAP. XIII.

By night we may make signs by fire, and with dust by day.

IT remains to shew whether we can make signs in the night by fire, and in the day by dust, to declare our business. That may fall out two ways: For by fire of a sudden, we shew to our confederate friends, or when we please, by certain numbers of Torches, we represent letters fit to demonstrate what our purpose is, that those that are far off, seeing and observing the motions may perceive our intent. The first way, we read that Medea promised to the Argonauts, that if she killed Pelias, she would signifie so much unto them by night with fire from a watch-Tower, and by day with smoke. When therefore the business was effected, as she would have it, she counterfeited, that she must pay her vows to the Moon, by making a fire, by lighting Torches in the open Air, from the top of the place, as she had promised, and when the Argonauts understood it this way, they invaded the Kings palace, and killing the guard, they made her to enjoy her wishes. We read also that Maga, having possession of Paretonium, agreed with the watch, that at night in the evening, and again in the morning be[…]imes, they should set up the light that was for confederacy; and by that means signs were made, that the messenger came as far as Clius. Also to friends that live out of the City, by fire we may signifie our revenew, and the quality of provision. It is apparent, that Annibal, as Polybius writes, when the people of Agrigentum were besieged by the Romans, by many and frequent fires by night, did shew forth the intolerable famine of his Army, and for that cause many of his Souldiers, for want of victuals, fell off to the enemy. Also the Grecians compacted with Sinon, that by night, when the Trojans were asleep, those that came to Troy should have a token, when he should open the Trojan Horse, to let forth the Souldiers that were within. Whence Virgil,

When the Kings fleet lift up the flames, just then
Did Sinon let forth all the Grecian men.

Also by Torches letters may be signified, as we find it in the Manuscript of Polybius. Tops of buildings or Towers, are very fit to set up the Torches on. Let the letters be divided into two or three parts, if there may be eleven, or seven parts of each. If they be seven, the first letters are shew'd by single Torches, the second by double ones, the third by three Torches. The number may be also divided into four parts: but in representing them, we must observe the variety of motion. For one Torch once lifted up, shall signifie A, the same lifted up twice B, thrice C; so seven times: the last of the first order G, after that two once H, so many twice I, thrice signifies L, and so of the rest of the same order. Then Q by the third order, once, R by the same, twice, and thrice as many of the same, signifies S, and so it holds for four. Thus a woman from a watch-Tower, with three lights shewed five times, then with double ones twice, then with treble lights twice, then again with one at once, and with the same four times, then five times with three lights, then thrice, and with as many four times, shall signifie, vir adest, the man is come. Also the lights may be of divers colours, if they would shew that friends are neer. Also by smoke, we may shew that our enemies are neer, or some other thing. Hence it was, that by the policy of Amilcar, the men of Agrigentum, being drawn off far from the City, amongst their enemies that they pursued, unto an ambuscado, where the enemies lay hid, and a by wood set on fire, suffered a great overthrow: for when they thought they were called back by their friends, by reason of a smoke they supposed to come from the walls; when they turned their course to go to the City, Amilcar commanding, the Carthaginians followed them, who fled before, and so slew them.