In Our Time

Melvyn Bragg and guests discuss how scientists sought to understand the properties of gases and the relationship between pressure and volume, and what that search unlocked. Newton theorised that there were static particles in gases that pushed against each other all the harder when volume decreased, hence the increase in pressure. Those who argued that molecules moved, and hit each other, were discredited until James Maxwell and Ludwig Boltzmann used statistics to support this kinetic theory. Ideas about atoms developed in tandem with this, and it came as a surprise to scientists in C20th that the molecules underpinning the theory actually existed and were not simply thought experiments. The image above is of Ludwig Boltzmann from a lithograph by Rudolf Fenzl, 1898 With Steven Bramwell Professor of Physics at University College London Isobel Falconer Reader in History of Mathematics at the University of St Andrews and Ted Forgan Emeritus Professor of Physics at the University of Birmingham Producer: Simon Tillotson

Melvyn Bragg and guests discuss Mary Shelley's (1797-1851) Gothic story of a Swiss natural philosopher, Victor Frankenstein, and the creature he makes from parts of cadavers and which he then abandons, horrified by his appearance, and never names. Rejected by all humans who see him, the monster takes his revenge on Frankenstein, killing those dear to him. Shelley started writing Frankenstein when she was 18, prompted by a competition she had with Byron and her husband Percy Shelley to tell a ghost story while they were rained in in the summer of 1816 at the Villa Diodati by Lake Geneva. The image of Mary Shelley, above, was first exhibited in 1840. With Karen O'Brien Professor of English Literature at the University of Oxford Michael Rossington Professor of Romantic Literature at Newcastle University And Jane Thomas Professor of Victorian and Early 20th Century Literature at the University of Hull Producer: Simon Tillotson

Melvyn Bragg and guests discuss the French philosopher Henri Bergson (1859-1941) and his ideas about human experience of time passing and how that differs from a scientific measurement of time, set out in his thesis on 'Time and Free Will' in 1889. He became famous in France and abroad for decades, rivalled only by Einstein and, in the years after the Dreyfus Affair, was the first ever Jewish member of the Académie Française. It's thought his work influenced Proust and Woolf, and the Cubists. He died in 1941 from a cold which, reputedly, he caught while queuing to register as a Jew, refusing the Vichy government's offer of exemption. With Keith Ansell-Pearson Professor of Philosophy at the University of Warwick Emily Thomas Assistant Professor in Philosophy at Durham University And Mark Sinclair Reader in Philosophy at the University of Roehampton Producer: Simon Tillotson

Melvyn Bragg and guests discuss the most destructive riots in London's history, which reached their peak on 7th June 1780 as troops fired on the crowd outside the Bank of England. The leader was Lord George Gordon, head of the Protestant Association, who objected to the relaxing of laws against Catholics. At first the protest outside Parliament was peaceful but, when Gordon's petition failed to persuade the Commons, rioting continued for days until the military started to shoot suspects in the street. It came as Britain was losing the war to hold on to colonies in North America. The image above shows a crowd setting fire to Newgate Prison and freeing prisoners by the authority of 'His Majesty, King Mob.' With Ian Haywood Professor of English at the University of Roehampton Catriona Kennedy Senior Lecturer in Modern British and Irish History and Director of the Centre for Eighteenth Century Studies at the University of York and Mark Knights Professor of History at the University of Warwick Producer: Simon Tillotson

Melvyn Bragg and guests discuss the life of Nero (37-68 AD) who became Emperor at the age of 16. At first he was largely praised for his generosity yet became known for his debauched lifestyle, with allegations he started the Fire of Rome, watching the flames as he played the lyre. Christians saw him as their persecutor, an anti-Christ, and the number of the Beast in the Book of Revelation was thought to indicate Nero. He had confidence in his own artistry, took up acting (which then had a very low status) and, as revolts in the empire grew, killed himself after the Senate condemned him to die as a slave, on a cross. With Maria Wyke Professor of Latin at University College London Matthew Nicholls Fellow and Senior Tutor at St John’s College, University of Oxford And Shushma Malik Lecturer in Classics at the University of Roehampton Producer: Simon Tillotson