You can try this one. Squeeze some lemon juices into a container. Wet a brush with the lemon juices and then write somethings on a piece of paper. After that, let it dry. I take it take about 10 minutes. You will notice that the words you have written will disappear in thin air without a single trace.
Put something hot, or use an iron on the paper. You can see that the words will re appear.
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