Invisible ink, often known as sympathetic ink, is a writing fluid that’s invisible underneath regular situations however could be revealed by warmth, gentle, or chemical response. It has been used for hundreds of years for secret communication, because it permits messages to be hidden in plain sight.
Invisible ink could be comprised of a wide range of supplies, together with lemon juice, vinegar, and milk. To write down with invisible ink, merely dip a pen or brush into the ink and write your message on paper. The message will likely be invisible till it’s heated, uncovered to gentle, or handled with a chemical reagent. This makes it a great strategy to ship secret messages, because the message could be simply hidden from prying eyes.
