The Rosetta Stone is a stele, or monument, found by Napoleon's troops near the town of Rosetta (now called Rashid), near Alexandria, Egypt.
The Rosetta Stone dates to about 196 BC and is inscribed with praises for the deeds of Pharoah Ptolemy V. What is significant about this stele is that the inscription is written three times in three different languages: Greek, Demotic, and hieroglyphic. Demotic is a form of the ancient Egyptian language. From the time archaeologists began studying ancient Egypt, they debated whether hieroglyphs were just decorative pictures or whether they represented a language. With the discovery of the Rosetta Stone, the debate was settled. French linguist Jean-Francois Champolion was the first to decipher the meaning of the pictures and made it possible for hieroglyphics to be translated.
The allusion to the Rosetta Stone in To Kill a Mockingbird is in reference to the snowman the children build. It is sort of a Rosetta Stone to foreshadow events to come.
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