Found a notebook in a library book with a recipe for 'invisible ink'

I mean, it was just a regular composition book tucked in a cookbook at the local branch. The page said to mix lemon juice with a little water and write with a toothpick, then heat the paper to reveal it. I tried it on some printer paper and held it over my stove. Instead of neat writing, the whole sheet just turned a gross brown and curled up. Maybe my heat was too high? Has anyone else actually gotten one of these old tricks to work without ruining the paper?

2 comments

2 Comments

charles_lewis141d ago

Oh man, I read you need a super low heat like a light bulb.

charles_green1d ago

Yeah, that "super low heat" thing is way off... A light bulb won't cut it for most stuff. You need a steady, even warmth, not just a tiny hot spot. Trust me, @charles_lewis14, that advice will leave you cold in a bad way. Seen it happen too many times. Gotta have a proper heat source.