Items to be used
to write with:
1) Matches stickes,
toothpicks put it really good (you have to dip it in
the ink between every letter)
Ink filling pens (now adays there is a pulp to be filled with ink, it can be
filled with the liquid ink, but if it is thick or
Contain solid particles; just dip the tip of the pen in the clear part of the
1) Lemon juice: (Any organic substance will char giving brown color like milk by writing
with cottonswap, sugar solution,..)
i) Squeeze a lemon and take
the concentrated juice.
you can use a mixture of (lemon: glycerin: honey=4:4:1)
Dip whatever you use to write in the juice, and then write on blank paper &
leave to dry.
For the message to appear:
a) Pass the paper over stove fire far enough from
fire so not burn it or
You can put it over a 100watt lamp or iron it.
Or pass a sponge containing diluted solution of iodine in water, message
will appear white on light blue or purple background.
2) Cornstarch suspension:
(Caution: Iodine is very toxic.)
Mix a concentrated solution of starch & water.
Heat the mixture on heat abit (thicken abit)
Write the message and leave to dry.
Sponge the message with diluted iodine (about 10drops iodine [from the
pharmacy] in half glass of water)
The message will appear dark blue or purple on light blue or purple background.
3) Ammonium Chloride (NH4Cl):
You can find it in the Expectorant tablets (must not coated with any colors or
if so scratch it) in the pharmacy.
Crush few tablets (may be 3 or 4) & dissolve in least amount of water (there
will be particles undissolved just ignore it)
Leave the particles to settle down then use the clear upper part of solution to
write the message.
It will appear over heat (candle may be used) quickly as yellow or brown colour,
4) Vinegar: i)
Use vinegar to write the message (you can use lemon juice or any acid or may be
basic as ammonia)
Prepare red cabbage water, which act as PH indicator or red onion.
How can you prepare it?
Cut the cabbage to pieces & added to least water with gentle boiling (boil on
light flame) till
The color of the water turns deep red or purple.
Spray the cabbage water on the vinegar paper which is acidic so the cabbage
indicator give it a red color.
It present in some laxative tablets (must not contain any colors).
Write with it & leave to dry then put it over a plate.
Use washing Soda solution (from packets); drop the soda solution on the paper
gently so that it spread over the message,
So the message appears in pink color.
In the real spying history: 1) Ammonia solution:
was used to make the paper white & hide the scratches of the pen & with some
ink the spy write on a paper
That covers the original one.
2) Ink made of Cobalt
oxide dissolved in nitric acid or hydrochloric acid, when you write with this
solution, the writing appear
In blue color if it is subjected to fire & disappears if you blow
your breath on it.
3) Some times spies
didn't write the secret message in the letter but on the right upper corner of
the envelope, so after removing the
stamp with steam, you can show the message & some times they wrote it on the
inner side of the envelope.
4) The chemists used
tincture iodine vapors to detect the secret writings, because writing on the
paper anyway cause the shift of the
Paper?s fibers, so the vapor settle on the shifted fibers causing the hidden
writing to be read so the spies wet the paper after writing
and press it & iron it so the paper fibers reset to its original state but
also after that a chemical substance was discovered that
can show any invisible writing either wetted or not or ironed or not.
5) The eggs were used
to hide the invisible ink messages:
i) The message is
written with the invisible ink on well-washed egg surface & can be appeared by
ii) The ink diffuses
through the eggshell to inside the egg, without leaving any visible indication
on the surface.
iii) The egg is
presented between large numbers of eggs, so the rural woman that sells the eggs
must watch over it,
To ensure that it reaches the desired person.
iiii) The spy boils
the egg for a long time, then carefully takeoff the shell covers the egg to see
6) The secret
invisible ink was usually hidden inside a drug container, as a perfume but the
coolest method is soaking
Any specific cloth in the ink solution and leave it to dry
then when the need comes to use it, he soaks the cloth in hot or
Warm water and squeezes it gently to extract the ink
7) Now adays there is
certain writings that can only be seen under UltraViolet lamps and some prints
on papers that you can't see it with your naked eyes but after scanning with
specific scanner, you get the hidden print.
8) There are some
spies who send photocards with a suitable clear area on it, in which he leaves a
copy of photos or microfilmst that it only one process to becom a real photo
(he shows a photo not on blank papers but on the blank areas of his photo, so
it won't appear except if somebody process it), this technique called
CAMOUFLAG , it was
first used by Germany in the first world war.
9) The invisible inks
weren't that easy as lemon juice & so.. But it needs complicated procedures to
ensure that the enemy's chemists.
Won?t discover it easily, it may require reactions in certain conditions only
the spy knows it.
There is Fluorescent
liquids and powders that can't be seen by our naked ordinary eyes but require
UV light to be seen like the image below and these liquids and inks can be used
in computer printers to generate secret prints on papers that can only be seen
after subjecting the paper to UV light and may be to UV with specific
wavelength..On the other hand there is small devices to detect objects or
papers with UV or Florescent marks with great sensitivity from respectable
distance ..Regarding the powder as I said in the spying world section, it is
used to protect sensitive places or subjects as the powder will stick to the
intruder and will not be even washed for a long time so the suspects can be
subjected to UV light to detect the powder on the MEANT person..Really great :)