February 13

• 1542 – Catherine Howard (pictured), the fifth wife ofHenry VIII of England, was executed for adultery.
• 1867 – Work began on the covering of the Senne, burying the polluted main waterway in Brussels to allow urban renewal in the centre of the city.
• 1880 – American inventor Thomas Edison observed theEdison effect, which later formed the basis of vacuum tube diodes designed by English electrical engineer John Ambrose Fleming.
• 1970 – The English rock band Black Sabbath released their eponymous debut album, which is recognised as the first major album to be credited with the development of the heavy metal genre.
• 1981 – Sewer explosions caused by the ignition of hexane vapors destroyed more than two miles (3 km) of streets in Louisville, Kentucky, US.
• 2010 – A terrorist bombing at a bakery popular among foreigners in Pune, India, killed 17 people and injured 60 more.