Secret Letter in Invisible Ink
The thrill of a good mystery is always enhanced by a letter written in invisible ink. The good news is that not all invisible ink is as expensive as other supplies for a secret agent are. In fact this science project involves making and using invisible ink to write you friend a letter that everyone else will think is a blank page.
So if you want to share your secrets with that one special friend here’s what you need to do. Get hold of a lemon from the fruit basket . Now squeeze out the juice in a bowl and get ready to write your letter. Milk is also a good substitute for invisible ink on plain white paper. Once you have finished writing your letter you need to let the paper dry so that what you have written does not get smudged.
Now fold it up and deliver it to your friend. Of course you will need to tell your friend just how to read the letter too. That’s also quite simple. The trick is to heat up the paper so that the invisible writing shows up. You can use the heat from a radiator to do so. Just make sure that if you use any other source of heat you are careful not to burn up the paper with the secret message. You can make a science project out of discovering what other material can make good invisible ink.