How to Make Invisible Ink

Make your message invisible to the naked eye. You can make invisible ink, and write with that. Even better: encode your message first, THEN write it in invisible ink. When it comes to your safety, there's no such thing as doing too much.

If you have little time, you can use a lemon to make invisible ink. The trick with lemon juice is that it IS invisible ink. You only have to press the juice out of a lemon, dip a crown pen or pointed feather in it, and write your secret message. Because it's colourless, it can't be seen after drying.
Only when you heat the paper, above a candle or with an iron, the lemon juice ink will discolor brown, and you'll be able to read it again.


Tip 1: Don't write your message on an empty page. An empty page is strange... why would you want to send an empty page to someone? When people start asking such questions, they may investigate further. So make sure you write a message on it. Something harmless, that anybody may read. Another idea is to write a message with loads of clues that lead nowhere, throwing your enemy off track.




Tip 2: Lemon juice invisible ink, while quick and handy, isn't completely invisible. It's a good idea to write on paper that's not white-white. Recycle paper is ideal for this.

Laser Listener - Hundreds of yards away Listen the conversation

Laser Window Bounce Listener

Hundreds of yards away, in the dark of night, behind elaborate security and a pane of glass, a conversation ensues which will determine your future.

Remarkable concept where you listen to sounds picked up from a reflecting surface illuminated by a laser. These light reflections, or scatter, are reproduced back to the original sound by our special optical receiver.

How Make Night Vision at home

Make Night Vision at home.

You can also buy Night Vision Yukon Advanced Optics 4x50 Night Vision Monocular