Italy used its current tri-colored flag for the first time.
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The first-ever photograph of genes was taken.
Beyoncé and Jay-Z welcomed their daughter, Blue Ivy Carter, into the world.
The US celebrated the opening of the country's first railroad station in Baltimore.
The iconic Leaning Tower of Pisa leaned 'too far,' which resulted in its closure.
President Truman announced to the people of America that they successfully developed a hydrogen bomb.
