Friday, March 18, 2011

Theory Thursday: Invisible Ink

What could be cooler than secret spy messages and hidden treasure maps? Not too much. Maybe a pet slug. That nearly was our science project yesterday when Jake found this little guy while playing in the backyard. I went into the house to find and wash the little aquarium. By the time I got back, Jake had caught the slug in an almost empty Pepsi bottle to keep it from escaping. Needless to say, it died. It must have been a Coke drinker.

Back to Plan A: invisible ink.

Gather water, lemon, paper, spoon, and q-tips.

Squeeze the juice out of the lemon.

Eat the lemon.

Mix a few drops of water into the juice and stir.

Eat more lemon.

Dip the q-tips in the mixture.

Write a secret message. Or eat more lemon.

Move into the house because the wind is blowing everything away, literally. Continue writing your message.

Take a break if you need to. While you're at it, eat more lemon.

Admire your creation and laugh at your adversaries since they'll never figure it out.

You could still see most of the drawings once the juice dried. (Sorry, no picture.) The paper was shrively. Leighton said that I should have used card stock instead of printer paper. We may not have diluted to juice enough though, or they used to too much liquid on the paper? We tried holding the paper by a light bulb to turn it brown. It didn't work. I think it was because we only have the swirly light bulbs. What are they called? Anyway, they don't get hot enough. We'll have to try it with a candle. The kids had plenty of fun holding the paper up to the light and seeing the "hidden" pictures. Anything spyish is a winner in Jake's book.
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  1. Twirly light bulbs are CFLs. Compact Flourescent Lights

  2. Thank you. I feel better knowing that. They are still twirly though!