One interesting theory on the cause of manic depression or bipolar disorder is that there is a super-fast biological clock located in the hypothalamus, in the center of the brain, which is actually a tiny cluster of nerves called the supra chiasmatic nucleus or SCN.
Since the release of the first novel, Harry Potter and the Philosopher's Stone, on 26 June 1997, the books have found immense popularity, critical acclaim and commercial success worldwide.
Final Harry Potter book released. On this day in 2007, the seventh and final Harry Potter novel, Harry Potter and the Deathly Hallows, is released, with an initial print run of 12 million copies in the United States alone. Like each of the previous Harry Potter novels, Deathly Hallows was slated to be made into a major Hollywood film.