Invisible Ink!

I led my first educational workshop today, on invisible ink and ciphers.

Developing lemon juice ink with an iron is a FAFF. Shalln't be bothering with that one again. It worked, but took for EVER. It became a serious timing problem with a group of 30.

However, Sodium Bicarbonate dissolved in water worked well. I developed that with red cabbage water, which turned the paper violet, and green where the ink had been painted. Very pleasing colours, and it even generated a few 'wow!'s. :D

Through a happy accident, it turns out that lemon juice is also developed with red cabbage water, turning quite a fetching magenta-pink. Not as clear as the green, but visible nevertheless.

If I were to do this again, I would try both lemon juice and sodium bicarbonate with red cabbage juice, and try to find another ink for a second one. Or possibly use white candles/wax to draw a message and wash over the cabbage water.

Anyway, I'm shattered, but I had fun. It seemed like some of the kids did too, despite the timing problems with the larger group.

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