Going by the pseudonym "X," Pope Leo XIII anonymously crafted poetic puzzles in Latin for a Roman periodical at the turn of the 19th century.
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The pope created lengthy riddles, known as "charades," in Latin in which readers had to guess a rebus-like answer from two or more words that together formed the syllables of a new word.
Eight of his puzzles were published anonymously in "Vox Urbis," a Rome newspaper that was printed entirely in Latin between 1898-1913, according to an article in the Vatican newspaper, L'Osservatore Romano.
A reader who submitted the correct answer to the riddle would receive a book of Latin poetry written by either Pope Leo or another noted Catholic figure.
The identity of the mysterious riddle-maker, however, was soon revealed by a French reporter covering the Vatican for the daily newspaper Le Figaro.
Felix Ziegler published his scoop Jan. 9, 1899, a year after the puzzles started appearing, revealing that "Mr. X" was, in fact, the reigning pope, the Vatican newspaper said July 20.
In the pope's hometown, Carpineto Romano, which is about 35 miles southeast of Rome, students at the middle school now named for him have published 26 of the pope's Latin puzzles in a new book titled, "Aenigmata. The Charades of Pope Leo XIII."
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