Meaning of ink: sympathetic ink in the Collier Dictionary. Sympathetic Ink What does "sympathetic ink" mean?

The use of sympathetic (invisible) ink implies an inscription that is indistinguishable under normal circumstances, but appears after chemical or physical development. This is a variant of steganography.

The process of using good sympathetic ink (not to mention making it...) involves the following nuances:

- the record is made on a sheet of high-quality paper with a thin and long wooden point soaked in the necessary ink (for example, a toothpick or a match wrapped in cotton wool), a thin felt-tip pen, or a thin brush; the main thing is that this “pen” does not scratch the paper;

- both before and after writing, the sheet is carefully smoothed on both sides in different directions with a soft cloth, hiding the cryptography in the surface layer of the paper;

- a sheet with cryptography is processed with steam, and then it is clamped between the pages of a voluminous book and dried well. If traces of “chemistry” appear on it or they are visible under ultraviolet rays, the record is rejected;

- if everything is in order - then on a sheet with hidden information they write an open letter or some other harmless texture (say, a poem ...).

Insuring against amateur attempts to reveal cryptographic writing using the “poke” method, you can use various tricks, including, say, nitriding the paper (it will flare up with excessive heat ...) or making a record with a “light pen” (LED ...) on paper that is very sensitive to light (the written disappears against the background from illumination when illuminated by daylight ...).

For the manifestation of cryptography, it is necessary to use the appropriate reagent and appropriate methodology. The developer itself is applied here by touching - wiping with a sponge (cotton swab), by spraying from a spray bottle, or in another available-optimal way. In temperature variations, ironing or heating near a light bulb is used.

Many of the substances that come to hand can be used as acceptable inks for cryptography: medicines, household chemicals, individual products, and even human excretions. A short list of sympathetic inks of this kind with a mention of their developer is presented below. Dry substances are dissolved here in water or in alcohol, and the concentration of the composition is established by experience.

1. Beer and white wine - the ashes of burnt paper (the text is slightly moistened by breathing ...).

2. Sugar water and factory apple juice - ashes of paper (when moistening the text).

3. Apple juice (when "dipping" into an apple) and milk (diluted)

- heating.

4. Onion and swede juice - heating.

5. Food citric acid - benzyl orange.

6. Pyramidone (in alcohol solution) - heating.

7. Astringents for disinfection of the mouth and throat - heating.

8. Aspirin - iron salts.

9. Phenolphthalein - any diluted alkali (say, slaked lime ...).

10. Alum - heating.

11. Sulfuric (battery) acid (at 10-15%) - heating.

12. Wax (at least somehow a pointed fragment of a candle ...) - calcium carbonate, or tooth powder (sprinkle and shake off).

13. Washing powder - the light of an ultraviolet lamp (say, from a currency probe ...).

14. Saliva - ink very diluted with water.

15. Urine - heating.

16. Blood - (with a fair dilution) - a weak (0.1%) solution of luminol (1 hour) with bicarbonate soda (5 hours).

Sometimes the method of so-called “water pressure” can turn out to be very convenient, following which you need to moisten a sheet of unlined paper with water and place it on some kind of glass substrate (say, on a mirror ...). Another dry paper sheet is placed on this sheet, and then the necessary text is written with a hard pencil or thick ballpoint pen. While the paper is wet, the text will be visible, and as soon as it dries, it will disappear. After the sheet becomes dry, some kind of camouflage message is written on it with water-insoluble ink. In order for the hidden message to appear, you just need to put the leaf in any water and immediately pull it back.

The use of sympathetic (invisible) ink implies an inscription that is indistinguishable under normal circumstances, but appears after chemical or physical development.

The process of using good sympathetic ink (not to mention their manufacture) includes the following nuances:

• the record is made on a sheet of high-quality paper with a thin and long wooden point soaked in the necessary ink (for example, a toothpick or a match in a cotton wrap), a thin felt-tip pen, or a thin brush. The main thing is that this “pen” does not scratch the paper.
• both before and after writing, the sheet is carefully smoothed on both sides in different directions with a soft cloth, hiding the cryptography in the surface layer of the paper.
• a sheet with cryptography is processed with steam, and then it is clamped between the pages of a voluminous book and dried well. If traces of “chemistry” appear on it or they are visible under ultraviolet rays, the record is rejected.
• if everything is in order, then an open letter or other safe text, a pencil drawing, a pen is written on a sheet with secret information.

In order to protect against amateur attempts to detect cryptographic writing using the "poke" method, various tricks can be used, including, say, nitriding the paper (it will flash when it is heated excessively) or making a "light pen" (LED) recording on paper that is very sensitive to light (the written will disappear against the background from illumination when illuminated by daylight).

To conduct cryptography, you must use the appropriate reagent and appropriate methodology. The developer itself is applied by touch - by rubbing with a sponge (cotton swab), by spraying from a spray bottle or by another available - in the best way. In temperature variations, ironing or heating is used.

Reagent Recipes

Dry substances are dissolved here in water or in alcohol, the concentration of the composition is established in practice.

1. Beer and wine. Developer –
2. Sugar water and factory-made apple juice. Developer – ashes of burnt paper (the text is slightly moistened by breathing).
3. Apple juice (when "dipping" into an apple) and milk (diluted). Developer – heating.
4. Onion and swede juice. Developer – heating.
5. Food grade citric acid. Developer – benzyl orange
6. Pyramidone (in alcohol solution). Developer – heating.
7. Astringents for disinfection of the mouth and throat. Developer – heating.
8. Aspirin. Developer – iron salts.
9. Phenolphthalein. Developer – dilute alkali (for example, slaked lime).
10. Alum. Developer – heating.
11. Sulfuric (battery) acid (at 10 - 15%). Developer – heating.
12. Wax (a pointed fragment of a candle). Developer – calcium carbonate, tooth powder. Sprinkle and shake.
13. Washing powder. Developer – ultraviolet lamp light.

The “water pressure” method can be very convenient, following which you need to moisten a sheet of unlined paper with water and place it on some kind of glass substrate (say, on a mirror). Another dry paper sheet is placed on this sheet and the necessary text is written with a hard pencil or an empty ballpoint pen. While the paper is wet, the text will be visible, and when it dries, the text will disappear. After the sheet becomes dry, some kind of camouflage message, an inscription is written on it with water-insoluble ink. In order for the hidden message to appear, you just need to wet the sheet a little.

Steganography

At the heart of this art is an attempt to hide the very existence of a secret message, and therefore its techniques deserve the widest use. Orienting examples of these techniques (leaving aside the possibilities created by electronics) can serve as:

• writing with a prick of letters in a specific place of a certain book or newspaper (the ends of words are marked with pricks between letters);
• the message of some data (a set of goods, wholesale prices) in a certain order;
• writing through knots;
• an entry on the side surface of a deck of cards selected in a certain order (the deck is then shuffled);
• records on the reverse side of the labels of vials, cans, bottles;
• text under a pasted postage stamp;
• record on the inner surface of the matchbox;
• a record inside a boiled egg (they take a mixture of alum, ink and vinegar, write what is needed on the shell of an ordinary egg, which is then kept in strong brine or vinegar to bleed traces from its surface; then the egg is boiled hard, and all the text is on top of the protein under the shell);
• the use of a “spoiled” typewriter, in which some letters are placed above or below the line (they take into account the order and number of these letters, as well as the intervals of their appearance; Morse code is possible in the code);
• broadcasting certain compositions on the air of the desired radio station, in a certain order or at a certain time;
• handwritten notes in a music book (notes have a value in Morse code or another code);
• records in the form of a cardiogram or a graph of a certain technological process (here, using Morse code, the higher peaks indicate a dash, and the lower ones indicate dots, dashes between teeth - a section between letters, line breaks - the end of a word);
• entries only in the vertical columns of a completely filled crossword puzzle (horizontal lines are filled arbitrarily, while the message itself can be either direct or encoded);
• stenciled entries, in which a stencil with windows cut out in it is superimposed on a sheet of note paper, following which the true message is entered; all the rest of the space is carefully filled with empty content, so, however, that the words of genuine information are clearly included in the text of a clear camouflage message.

List of used literature

The use of sympathetic (invisible) ink implies an inscription that is indistinguishable under normal circumstances, but appears after chemical or physical development. This is a variant of steganography.

The process of using good sympathetic ink (not to mention making it...) involves the following nuances:

The recording is made on a sheet of high quality paper with a thin and long wooden point soaked in the necessary ink (for example, a toothpick or a match wrapped in cotton), a thin felt-tip pen, or a thin brush; the main thing is that this "pen" does not scratch the paper;

Both before and after writing, the sheet is carefully smoothed out on both sides in different directions with a soft cloth, hiding the cryptography in the surface layer of the paper;

The sheet with cryptography is processed with steam, and then it is clamped between the pages of a voluminous book and dried well. If traces of "chemistry" appear on it or they are visible under ultraviolet rays, the record is rejected;

If everything is in order, then an open letter or some other harmless texture (say, a poem ...) is written on a sheet with hidden information.

Insuring against amateur attempts to reveal cryptographic writing using the "poke" method, you can use various tricks, including, say, nitriding the paper (it will flare up with excessive heat ...) or making a record with a "light pen" (LED ...) on paper that is very sensitive to light (the written disappears against the background from illumination when illuminated by daylight ...).

For the manifestation of cryptography, it is necessary to use the appropriate reagent and appropriate methodology. The developer itself is applied here by touching - wiping with a sponge (cotton swab), by spraying from a spray bottle, or in another accessible-optimal way. In temperature variations, ironing or heating near a light bulb is used.

As an acceptable ink for cryptography, you can use many of the substances that come to hand: medicines, household chemicals, individual products, and even human excretions. A short list of sympathetic inks of this kind with a mention of their developer is presented below. Dry substances are dissolved here in water or in alcohol, and the concentration of the composition is established by experience.

1. Beer and white wine - the ashes of burnt paper (the text is slightly moistened by breathing ...).

2. Sugar water and factory apple juice - ashes of paper (when moistening the text).

3. Apple juice (when "dipping" into an apple) and milk (diluted) - heating.

4. Onion and swede juice - heating.

5. Food citric acid - benzyl orange.

6. Pyramidone (in alcohol solution) - heating.

7. Astringents for disinfection of the mouth and throat - heating.

8. Aspirin - iron salts.

9. Phenolphthalein - any diluted alkali (say, slaked lime ...).

10. Alum - heating.

11. Sulfuric (battery) acid (at 10-15%) - heating.

12. Wax (at least somehow a pointed fragment of a candle ...) - calcium carbonate, or tooth powder (sprinkle and shake off).

13. Washing powder - ultraviolet lamp light (say, from a currency probe ...).

14. Saliva - ink very diluted with water.

15. Urine - heating.

16. Blood - (with a fair dilution) - a weak (0.1%) solution of luminol (1 hour) with bicarbonate soda (5 hours).

Sometimes the so-called "water pressure" method can be very convenient, following which you need to moisten a sheet of unlined paper with water and place it on some kind of glass substrate (say, on a mirror ...). Another dry paper sheet is placed on this sheet, and then the necessary text is written with a hard pencil or thick ballpoint pen. While the paper is wet, the text will be visible, and as soon as it dries, it will disappear. After the sheet becomes dry, some kind of camouflage message is written on it with water-insoluble ink. In order for the hidden message to appear, you just need to put the leaf in any water and immediately pull it back.

Appendix 1. Schemes of special equipment.

The presence of special equipment can dramatically increase the business potential of a scout in any complex game.

The official sale of such little things is partially limited, although in the wild market you can find both branded samples and clumsy fakes of domestic counterfeiters.

They can come with a hefty price tag, inconsistent parameters, and decrypted data that play into the hands of your opponents, especially if the shipment is made to order.

Excessive contacts can lead to unnecessary trouble. But very often you can get by with rather primitive means of completely independent production. Other reasons for such self-activity may be a sudden need and limited opportunities of a financial or situational kind.

The schemes of the special equipment presented below are proposed by M. Shustov, G. Tai and other domestic and foreign amateurs and professionals. (Useful additional information on this subject can be found, for example, in the reference book by V.I. Andrianov, V.A. Borodin, A.V. Sokolov "Spy Things" (St. Petersburg "Lan", 1996).

Rice. 9. Indicators for finding the desired telephone line.

a) on a neon lamp (the handset is on - it burns in the forward direction and does not light in the opposite direction; the handset is off - it does not light in any position; call - flashes with opposite polarity);

b) on the LED (flash on call).

Rice. 10. Induction taps for a telephone line.

a) using a core from a ferrite antenna (coil - 600 turns of PEL 0.06 mm);

b) using an armored core (when connected, the cups are moved apart and one core of the line is inserted inside the magnetic circuit; the coil is 600 turns of PEL 0.06 mm).

Rice. 11. Schemes of serial radio bugs: a) range: 65-108 MHz; range: 10-15 m; L1-8V, 0.5 d=4, L2 - 3V, d=0.5;

Rice. 11. Schemes of serial radio bugs (continued): b) range: 65-108 MHz; range: up to 300 m; antenna: piece of wire 15-60 m, L1 - 2 + 2V, 0.5 x 5; L2 - 2V 0.5 over L1.

Back in the 1st century AD. Philo of Alexandria described a recipe for sympathetic ink made from the juice of ink nuts, which required a solution of iron-copper salt to develop. Ovid suggested using milk as an invisible ink (appears after heating). Invisible ink continued to be used both in the Middle Ages and in modern times, for example, in letters from Russian revolutionaries from prisons. The secret text, written in milk between the lines of a seemingly harmless ordinary letter, appeared when the paper was ironed with a hot iron. The tsarist secret police knew about this secret correspondence and successfully read it.

	Developer
Citric acid (food)	Benzyl Orange
	CaCO3 or tooth powder
Apple juice
swede juice
Pyramidone (in alcohol solution)
Astringents for mouth and throat disinfection
	Very weak aqueous ink solution
Urine (fresh)
Phenolphthalein	diluted lye
Laundry detergent (with optical brightener)	UV lamp light
	Iodine tincture
	iron salts

information safe sympathetic

A variety of substances can be used as sympathetic ink:

The Russian Tsar Peter I was engaged not only in compiling ciphers, but also paid due attention to the use of sympathetic ink. So, in April 1714, the tsar wrote to the Russian ambassador to Sweden I. Trubetskoy: “I am sending you three vials for a secret letter: what do they write under A., ​​which will go into paper and will not know anything; then under V. - ink themes then write whatever you want clearly; and the third under S. - when you receive a letter from us, they will anoint it, then the ink will come off, and the first will come out.

In the 18th century, the head of the College of Foreign Affairs of Russia, N. Panin, recommended in special cases to use sympathetic ink to write cipher text between lines of visible text and send these letters by a special courier, and not by mail. In one of his letters to Berlin, N. Panin wrote: “Not having sympathetic ink at hand, which I usually resort to, today, when writing the attached letter, I used lemon juice. Therefore, during processing, it should not be lowered into nitric acid, but should be heated.

In 1797, the wife of the future Russian Emperor Alexander I, Grand Duchess Elizaveta Alekseevna, in correspondence with her mother, used milk and advised her relatives: “Instead of holding the letter over the fire, you can also sprinkle it with coal powder; this makes what is written visible and thus it is possible to write on both sides.”

Sympathetic ink.- This name refers to liquids that, when written, do not leave any color trace on paper; the latter should appear only when heated, wetted with water, some juice, a solution of some salt or other substance, according to the chemical nature of the constituent part of this S. ink. The title "S. ink" was introduced at the end of the 17th century. Lemort in Leiden; he called by this name a solution of lead sugar Pb (CH 3 COO) 2, and what is written as such becomes noticeable after treatment with hydrogen sulfide; a similar phenomenon, however, had already been described earlier, in 1653, in a work by P. Borel published in Paris. Another type of S. ink is prepared from cobalt salts; what was written last in the cold is not noticeable, but with slight heating, letters of a beautiful blue color appear (anhydrous salts of cobalt are formed - blue); when cooled, under the influence of moisture in the air, these letters disappear again and can be again caused by heating. This discovery was attributed to the French chemist Bello (1737), but, apparently, it was made earlier, as far back as in the XV table. Paracelsus made one drawing, which was supposed to depict a winter landscape, covered with green foliage with low heating and thus turning into a summer one. Now black C. ink is prepared either using, as indicated above, lead sugar, or nitrogen-bismuth salt; what is written is then covered with an aqueous solution of hydrogen sulfide for development, and black lead sulfide or bismuth is formed. You can also use a solution of sublimate and for the development of a solution of tin chloride, whereby metallic mercury is released in the form of microscopically small brown balls. Black S. ink, essentially similar to ordinary ink, can be obtained if a solution of iron sulfate is used for writing, for developing, a decoction of ink nuts, etc. Blue: for writing, they use a solution of nitrogen-cobalt salt, for manifestation - oxalic acid, and a blue precipitate of oxalo-cobalt salt is formed; then you can use a solution of iron sulfate for writing, for manifestation - red blood salt: the so-called. turnbull blue, etc. Yellow. They write with antimony chloride, call it with a decoction of tanning nuts, or write with weakly basic lead vinegar and call it with potassium iodide, which produces yellow lead iodide. A weak solution of copper chloride also produces beautiful letters, which become noticeable only when heated and disappear again when cooled. Greens C. ink consists of a solution of cobalt chloride, to which a certain amount (eg until the aqueous solution becomes discolored) is mixed with nickel chloride, ferric chloride, or even ammonia; written after drying is completely imperceptible, with slight heating, a beautiful green color appears. Another recipe for beautiful green ink is that it is written with a colorless solution of arsenic-potassium salt and developed with a solution of nitrogen-copper salt. purple color it turns out written if you write with a solution of gold chloride and moisten the written with a solution of tin chloride, this forms the so-called. Cassian purple. They also write with a very dilute, slightly acidified solution of ferric chloride, and then, for development, they place what is written in a vessel, on the bottom of which is poured a little strong sulfuric acid and a solution of cadium thiocyanate; developing vapors of rhodanic acid cause reddening of the writing due to the formation of thiocyanate; if they want to destroy the caused red coloration, they place the written in an atmosphere containing ammonia vapor; in this case, the staining disappears and can be caused again any number of times. purple pink A shade of ink is obtained by mixing cobalt chloride with zinc sulphate, etc. In general, it should be borne in mind that C. ink is only then good and almost invisible before development, if you work with solutions as diluted as possible. To recognize the presence of strokes made by S. in ink on white paper or between lines written in ordinary ink, suspicious paper is placed between plates of white glass, the latter are strongly pressed against each other and examined carefully in incident (reflected) and transmitted light. Often this makes it possible to directly read even completely colorless strokes. Otherwise, a series of indirectly intersecting lines is drawn on suspicious paper using goose feathers dipped in various reagents, such as: diluted acetic acid, hydrogen sulfide water, ammonium sulfide, iodine water, solutions of iron, copper sulfate, sublimate, nitrogen-silver salt, ferric chloride, yellow and red blood salt, lead sugar, tannin, etc. If any of the reagents gives a positive As an indication, it is not difficult to find an appropriate solution for the manifestation of everything written.