learn how to make invisible ink to write secret messages. Craft of a spy technique for writting using invisible color.

How to make invisible ink

¡Write secret messages with invisible ink and transmite secure information!



Good spies transmit important information in a secret way. To do so, it's necessary to write messages in a certain way for avoiding the other people to read them. Just real spies will know the secret messages.

The following materials are needed: a couple of lemons, a squeezer, a shot glass, cotton swabs, a pencil, a paper sheet, a candle and matches.

Write the secret message



First elaborate the invisible ink.

Take the lemons and squeeze them to extract all their juice.

Pour the juice into the shot glass.



Write the secret message.

Take a cotton swab and get it into the juice of the shot glass. Now, write your message in the paper sheet with the cotton swab like it was a pencil.

When the juice is dry it will be impossible to see anything written in the sheet of paper.


To avoid arouse suspicion write in the other side of the paper a shopping list with a normal pencil.

We are ready to give the paper to our confident like we were asking him/her to go shopping.

Finish the transaction with a wink to let him/her know that shopping list is a secret message.


Reading the secret message



To read the secret mesege, first, light the candle with a match. Take care with the fire.

Then, put the sheet of paper with the hidden message on the candle to let the fire heat the paper. The flame will burn the lemon juice and will yellow it.



The invisible ink will show up again and we will read the message.

Remember that this invisible ink has lot of C vitamin!


More spy crafts at the following page: Spy Crafts

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