Later that evening after my parents had put me to bed I snuck the book out of my backpack, curled up under my sheets, took out my flashlight, and started to read. The first few pages were covered in weird calligraphy. I guessed it was Latin or Greek considering the curves and shape of the letters. In school I was learning Latin so I was able to make out a couple of words but most was beyond my understanding. The next several pages were filled with diagrams of machines and architecture. A few even looked liked some of the older homes around my town. After the diagrams, the pages were blank, but I learned that in the in the 17 and 18 centuries people created an ink that would only show when exposed to heat or special chemicals. A recipient of a letter with invisible ink would hold their letter over a flame or place the letter into a bowl with a certain chemical for the writing to appear.

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