Use an invisible ink to leave a message. Reveal the message by touching a flame to the edge of the writing, causing it to burn away in smoldering flame. The paper is left untouched, except for the fire writing.
Fire Writing Materials
- potassium nitrate (available in stores or make it)
- paper (heavy, relatively absorbent paper works best, like parchment paper)
Prepare Your Message
- Mix potassium nitrate into a very small amount of warm water to make a saturated potassium nitrate solution. It is fine if there is undissolved potassium nitrate.
- Dip a paintbrush, cotton swab, toothpick, fingernail, etc. into the solution and use it to write a message. You want to start the message or design at the edge of the paper. The lines of the message must be continuous since the fire will travel from the edge of the paper along the writing. You may wish to re-trace the message to make sure there is potassium nitrate on all parts of it.
- Allow the paper to dry completely. Your message will be invisible, so I hope you know where it started!
- Touch the edge of the paper, where the invisible message started, with the tip of a lit cigarette or with the flame of a lighter. The message will ignite and burn in smoldering fire until it is completely revealed. If you were careful only to light the edge of the message, the rest of the paper will remain intact.