Siddons, Sarah, the greatest tragic actress of England, born at Brecon, the daughter and eldest child of Roger Kemble, manager of an itinerant theatrical company; became early a member of her father's company, and at 19 married an actor named Siddons who belonged to it; her first appearance in Drury Lane as Portia in 1755 was a failure; by 1782 her fame was established, after which she joined her brother, John Kemble, at Covent Garden, and continued to act there till her retirement in 1812; she was distinguished in many parts, and above all Lady Macbeth, in which character she took farewell of the stage; she appeared once again in London after this in 1815, for the benefit of her brother Charles, and again a few nights in Edinburgh in aid of a widowed daughter-in-law (1755‒1831).
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Sicyon * Sidereal Year