Plot: In the last instalment of the series, viewers get the chance to show off their ideas for hovercraft, ice lenses, scientific musical instruments and bar-snack separators - all responses to the challenges inspired by the scientific heroes examined by Adam Hart-Davis in the last six weeks. Hart-Davis also heads for the East Midlands, where he turns his bicycle into a spinning machine to demonstrate the invention of Richard Arkwright, whose own version replaced 96 skilled workers with just one operator