Design of the Dark Mark

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Harry, fear spreading up his numb legs, watched Riddle stop between the high pillars and look up into the stone face of Slytherin, high above him in the half-darkness. Riddle opened his mouth wide and hissed - but Harry understood what he was waying... "Speak to me, Slytherin, greatest of the Hogwarts Four." ... "Slytherin's gigantic stone face was moving. Horrorstruck, Harry saw his mouth opening wider and wider to make a huge black hole. And something was stirring inside the statue's mouth. Something was slitering up from its depths. ... Something huge hit the stone floor of the Chamber. Harry felt it shudder - he knew what was happening, he could sense it, could almost see the giant serpent uncoiling itself from Slytherin's mouth."	Book 2, Pages 317-318 Chamber of Secrets, Chapter 17, "The Heir of Slytherin"
Then he realized that it was a colossal skull, comprised of what looked like emerald stars, with a serpent protruding from its mouth like a tongue. As they watched, it rose higher and higher blazing in a haze of greenish smoke, etched against the black sky like a new constellation. ... "It's the Dark Mark, Harry!" Hermione moaned, pulling him as hard as she could. "You-Know-Who's sign!"	Book 4, Pages 128-129 Goblet of Fire, Chapter 9, "The Dark Mark"
Voldemort bent down and pulled out Wormtail's left arm; he forced the sleeve of Wormtail's robes up past his elbow, and Harry saw something upon the skin there, something like a vivid red tattoo - a skull with a snake protruding from its mouth - the image that had appeared in the sky at the Quidditch World Cup: the Dark Mark.	Book 4, Pages 645 Goblet of Fire, Chapter 33, "The Death Eaters"
PONDER THIS
Harry remembered how the snakelike face of Voldemort had once forced itself out of the back of Professor Quirrell's head, and he ran his hand over the back of his own, wondering what it would feel like if Voldemort burst out of his skull. ...	Book 5, Page 492 Order of the Phoenix, Chapter 23, "Christmas on the Closed Ward"

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