Part 1
The Elisabeth Tower has it's name since 2012. Before that, the tower was known as The Clock Tower. In honor of Queen Elisabeth, on the occasion of her Diamond (60th) Jubilee, it was renamed.
It is said that the melody played on the bells is a variation of the four notes from bars 5 and 6 of the aria 'I Know That My Redeemer Liveth' from the oratorio Messiah by Georg Friedrich Händel. With Messiah, Händel set the Christian creed to music in the summer of 1741.
Big Ben always rings! For the British, it was very unusual to not her its meldony in the last few years due to the restoration of the tower. Usually, the bells only remain silent when a funeral of famous personalities take place (such as those of Winston Churchill or Margaret Thatcher).
To this day it is not entirely clear why the bell itself is called Big Ben. Officially, the bell is only called Great Bell. The consensus is that the bell got its nickname from Sir Benjamin Hall, whose name is engraved on the bell, and who coordinated the installation of the bell. According to a modern legend, however, the bell was named after Benjamin Caunt, a 19th-century boxer. He, too, bore the nickname Big Ben, after becoming the heavyweight champion of England in 1841.