It means 'before trees' and specifically refers to a time immediately after the last ice age in Britain, from about 9600BCE until about 8800BCE.
Preboreal
Fact of the Day
When President Lyndon Johnson was asked by members of the press why American soldiers were in Vietnam, he unzipped his trousers, pulled out what lay beneath and said 'This is why!'
Quote of the Day
"In this country, it is good to kill an admiral from time to time, in order to encourage the others.
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~ Voltaire on Admiral Byng's execution
On This Day
43 BCE The assassination of Cicero, requested by Marc Antony. When his head was delivered to Anthony, his wife, Fulvia, spat on it and jabbed hairpins into his tongue.
1732 The Theatre Royal, now known as the Covent Garden Opera House, opened with a performance of the Beggar's Opera.
1787 Delaware became the first state of the modern United States.
1817 Rear-Admiral William Bligh died. He had been captain of HMS Bounty during the mutiny.
1941 The Japanese launched a surprise attack on the American naval base a Pearl Harbour, Hawaii, killing 2,403.
1982 Charles Brooks Jr became the first person to be executed by lethal injection, with a huge dose of 'truth serum'