Overview: Eric Knowles and the team are at the National Botanic Garden of Wales in Carmarthen. Kate Bliss and Ben Cooper are guiding the reds and blues, who have £300 to spend on three items that they hope will make them a profit at the auction in Cardiff. Eric travels to a small seaside town in south Wales to find out how a stained glass window, made in south Wales by local artist John Petts, became an iconic image of the American Civil Rights movement in the 1960s.