Cycles in the Earth's climate, caused by changes in its relationship with the Sun.
The Milankovitch Cycles
Fact of the Day
Accounts from 1350 reveal that it cost 6d a day to keep a lion in the menagerie at the Tower of London, but to keep a prisoner cost only 1d.
Quote of the Day
"They are well named, for they have the countenance of angels, and as such should be coheirs with the angels in heaven. "
~ Pope Gregory I on the Angles, recorded by Bede
On This Day
1837 The civil registration of all births, marriages, and deaths, became compulsory in England and Wales.
1858 Charles Darwin and Alfred Russel Wallace's papers on evolution were read at the Linnean Society in London.
1867 Canada became a self-governing dominion in the British Empire, following the British North America Act. However, it didn't become fully independent until the passage of the Canada Act in 1982.
1916 The Battle of the Somme, often considered to be one of the bloodiest and most futile offensives of the First World War, started at 7.30am. The first day was gruelling, with almost 20 per cent of the British army killed, but the battle would rage on for a further three and a half months.
1934 Ernst Röhm, leader of the Storm Troopers (SA), was shot dead by the SS on Hitler's orders during the Night of the Long Knives, the purge that removed 'inconvenient' elements from the Nazi Party and helped Hitler to consolidate his power.
1969 Queen Elizabeth invested Prince Charles as Prince of Wales at Caernarfon Castle.
2007 The ban on smoking in enclosed public spaces in England came into effect.