Melvyn Bragg and guests discuss megaliths - huge stones placed in the landscape, often visually striking and highly prominent.

Such stone monuments in Britain and Ireland mostly date from the Neolithic period, and the most ancient are up to 6,000 years old. In recent decades, scientific advances have enabled archaeologists to learn a large amount about megalithic structures and the people who built them, but much about these stones remains unknown and mysterious.

With

Vicki Cummings

Julian Thomas

and

Susan Greaney

Paul Erdős (1913 – 1996) is one of the most celebrated mathematicians of the 20th century. During his long career, he made a number of impressive advances in our understanding of maths and developed whole new fields in the subject.

He was born into a Jewish family in Hungary just before the outbreak of World War I, and his life was shaped by the rise of fascism in Europe, anti-Semitism and the Cold War. His reputation for mathematical problem solving is unrivalled and he was extraordinarily prolific. He produced more than 1,500 papers and collaborated with around 500 other academics.

He also had an unconventional lifestyle. Instead of having a long-term post at one university, he spent much of his life travelling around visiting other mathematicians, often staying for just a few days.

With

Colva Roney-Dougal

Timothy Gowers

and

Andrew Treglown

The image above shows a graph occurring in Ramsey Theory. It was created by Dr Katherine Staden, lecturer in the School of Mathematics at the Open University.

In 1957 Stevie Smith published a poetry collection called Not Waving But Drowning – and its title poem gave us a phrase which has entered the language.

Its success has overshadowed her wider work as the author of more than half a dozen collections of poetry and three novels, mostly written while she worked as a secretary. Her poems, printed with her pen and ink sketches, can seem simple and comical, but often beneath the surface lurk themes of melancholy, loneliness, love and death.

With

Noreen Masud

and

Will May

The photograph above shows Stevie Smith recording her story Sunday at Home, a finalist in the BBC Third Programme Short Story competition in 1949.

On 21 May 1838 an estimated 150,000 people assembled on Glasgow Green for a mass demonstration. There they witnessed the launch of the People’s Charter, a list of demands for political reform. The changes they called for included voting by secret ballot, equal-sized constituencies and, most importantly, that all men should have the vote.

The Chartists, as they came to be known, were the first national mass working-class movement. In the decade that followed, they collected six million signatures for their Petitions to Parliament: all were rejected, but their campaign had a significant and lasting impact.

With

Joan Allen

Emma Griffin

and

Robert Saunders

The image above shows a Chartist mass meeting on Kennington Common in London in April 1848.

Melvyn Bragg and guests discuss the pioneering Danish astronomer Tycho Brahe (1546 – 1601) whose charts offered an unprecedented level of accuracy.

In 1572 Brahe's observations of a new star challenged the idea, inherited from Aristotle, that the heavens were unchanging. He went on to create his own observatory complex on the Danish island of Hven, and there, working before the invention of the telescope, he developed innovative instruments and gathered a team of assistants, taking a highly systematic approach to observation. A second, smaller source of renown was his metal prosthetic nose, which he needed after a serious injury sustained in a duel.

The image above shows Brahe aged 40, from the Atlas Major by Johann Blaeu.

With

Ole Grell

Adam Mosley

and

Emma Perkins

Melvyn Bragg and guests discuss the discovery made in 1911 by the Dutch physicist Heike Kamerlingh Onnes (1853-1926). He came to call it Superconductivity and it is a set of physical properties that nobody predicted and that none, since, have fully explained. When he lowered the temperature of mercury close to absolute zero and ran an electrical current through it, Kamerlingh Onnes found not that it had low resistance but that it had no resistance. Later, in addition, it was noticed that a superconductor expels its magnetic field. In the century or more that has followed, superconductors have already been used to make MRI scanners and to speed particles through the Large Hadron Collider and they may perhaps bring nuclear fusion a little closer (a step that could be world changing).

The image above is from a photograph taken by Stephen Blundell of a piece of superconductor levitating above a magnet.

With

Nigel Hussey

Suchitra Sebastian

And

Stephen Blundell

Producer: Simon Tillotson

Melvyn Bragg and guests discuss A Theory of Justice by John Rawls (1921 - 2002) which has been called the most influential book in twentieth century political philosophy. It was first published in 1971. Rawls (pictured above) drew on his own experience in WW2 and saw the chance in its aftermath to build a new society, one founded on personal liberty and fair equality of opportunity. While in that just society there could be inequalities, Rawls’ radical idea was that those inequalities must be to the greatest advantage not to the richest but to the worst off.

With

Fabienne Peter

Martin O’Neill

And

Jonathan Wolff

Producer: Simon Tillotson

Melvyn Bragg and guests discuss Donne (1573-1631), known now as one of England’s finest poets of love and notable in his own time as an astonishing preacher. He was born a Catholic in a Protestant country and, when he married Anne More without her father's knowledge, Donne lost his job in the government circle and fell into a poverty that only ended once he became a priest in the Church of England. As Dean of St Paul’s Cathedral, his sermons were celebrated, perhaps none more than his final one in 1631 when he was plainly in his dying days, as if preaching at his own funeral.

The image above is from a miniature in the Royal Collection and was painted in 1616 by Isaac Oliver (1565-1617)

With

Mary Ann Lund

Sue Wiseman

And

Hugh Adlington

Melvyn Bragg and guests discuss the stench from the River Thames in the hot summer of 1858 and how it appalled and terrified Londoners living and working beside it, including those in the new Houses of Parliament which were still under construction. There had been an outbreak of cholera a few years before in which tens of thousands had died, and a popular theory held that foul smells were linked to diseases. The source of the problem was that London's sewage, once carted off to fertilise fields had recently, thanks to the modern flushing systems, started to flow into the river and, thanks to the ebb and flow of the tides, was staying there and warming in the summer sun. The engineer Joseph Bazalgette was given the task to build huge new sewers to intercept the waste, a vast network, so changing the look of London and helping ensure there were no further cholera outbreaks from contaminated water.

The image above is from Punch, July 10th 1858 and it has this caption: The 'Silent Highway'-Man. "Your Money or your Life!"

With

Rosemary Ashton

Stephen Halliday

And

Paul Dobraszczyk

Melvyn Bragg and guests discuss Jane Austen’s last complete novel, which was published just before Christmas in 1817, five months after her death. It is the story of Anne Elliot, now 27 and (so we are told), losing her bloom, and of her feelings for Captain Wentworth who she was engaged to, 8 years before – an engagement she broke off under pressure from her father and godmother. When Wentworth, by chance, comes back into Anne Elliot's life, he is still angry with her and neither she nor Austen's readers can know whether it is now too late for their thwarted love to have a second chance.

The image above is from a 1995 BBC adaptation of the novel, with Amanda Root and Ciarán Hinds

With

Karen O’Brien

Fiona Stafford

And

Paddy Bullard

Producer: Simon Tillotson