The Forum

China, Iran, Afghanistan, Syria, Uzbekistan and India: if you went to any of these places a thousand years ago, you would find goods and produce from the others. But how did they get there and why? This week’s Forum explores the ancient pattern of trading networks which criss-crossed the plains, deserts and mountains of China, Central Asia and points further West, and which encouraged not just the exchange of commodities like silk, paper and horses but ideas and people too.Bridget Kendall talks to Valerie Hansen, professor of history at Yale University who has a particular interest in trade and exchanges across Eurasia; historian Dr. Susan Whitfield who is curator of the Central Asian collections at the British Library in London; and Tamara Chin, professor of comparative literature at Brown University whose work focuses on ancient China.Photo: A man rides a horse overlooking Band-e-Amir lake, through central Afghanistan, on the former Silk Road that once linked China with Central Asia and beyond. Credit: Getty Images

At the time of the Partition of India 70 years ago this year, there were more than 500 Princely States. These were states nominally ruled by Indian Princes but ultimately under the control of the British colonial powers. Many of these princes - male and female members of the Royal Family - had kingdoms dating back to the 8th and 9th Centuries. But after the British curbed their powers, was their role largely ceremonial or did they have a deeper impact on the Indian people? And how did these Princes survive after Partition? Joining Rajan Datar is the writer and historian William Dalrymple, the director of the King’s College London India institute Sunil Khilnani, and the Indian social scientist Nikita Sud from Oxford University.(Photo: A view of the Umaid Bhawan Palace, set high above the desert city of Jodhpur in Rajasthan. Credit: Getty Images)

150 years ago three British North American colonies came together to form what was to become the world’s second largest country.To explain how this union came about and who the key players were, Bridget Kendall talks to historians Margaret Macmillan, Phillip Buckner and Sean Kheraj.Photo: The Canadian flag at an ice-hockey game (GETTY IMAGES)

Why do humans have such a long period of immaturity? And how have our ideas about childhood changed through the ages and across the world? Bridget Kendall explores some of the key moments and figures in the history of childhood, including Confucian China, Victorian factories and the 'endless childhood' that some young people seem to be living today. Her guests are Alison Gopnik, Professor of Psychology and Philosophy at the University of California, Berkeley; Ping-chen Hsiung Professor of History at the Chinese University of Hong Kong; and Hugh Cunningham Professor of Social History at the University of Kent.Photo: a young girl walks through an entrance to a walled garden (BBC)

Since appearing in print in the late nineteenth century, Sherlock Holmes has become one of the world’s most famous detectives, known for solving crime and mystery in London and beyond. But who was the man that made this fictional super-sleuth? And what inspired him to write?Bridget Kendall explores the life and work of Sir Arthur Conan Doyle - the doctor and literary superstar who embraced both science and the spiritual world - and who changed crime fiction forever.She’s joined by biographer Andrew Lycett and the scholars Catherine Wynne and Stefan Lampadius.Photo: Sir Arthur Conan Doyle (Getty Images)

Many of us can find the time of day quickly and accurately but where did the idea of time keeping originate and how did our ancestors manage without the instant access we take for granted today?From ancient shadow and water clocks to the latest super accurate optical clocks, Bridget Kendal explores time keeping with the Curator of the Royal Observatory in London, Dr Louise Devoy, the Director of the Museum of the History of Science in Oxford, Dr Silke Ackermann and watch and clock expert Grégory Gardinetti from the Fondation de la Haute Horlogerie in Geneva.Photo: World Clocks (Credit: EyeWire, Inc.)

Perhaps the island of Taiwan makes you think of those familiar "Made in Taiwan" labels on computer and electrical goods but it was nicknamed 'Ilha Formosa' or the 'beautiful island' by the Portuguese in the 1500s. Bridget Kendall explores its rich and surprising history with Emma Teng, Professor of Asian Civilisations at the Massachusetts Institute of Technology (MIT), Dr Jie Yu, Head of China Foresight, focused on Chinese foreign policy, at the London School of Economics and Dr Bi-yu Chang and Dr Dafydd Fell from SOAS (formerly known as the School of Oriental and African Studies) in London. Photo: people celebrate Taiwan' s annual Lantern Festival, which marks the end of the Lunar New Year festivities. (Getty Images)

This year is the 80th anniversary of the record-breaking attempt by the US aviator Amelia Earhart to circumnavigate the globe. It was a mission that cost her life, but helped to cement her place in history as one of the most inspirational and celebrated pilots of the 20th century. Bridget Kendall looks back at the life of a pioneering woman determined to break through barriers - with Susan Butler, author of ‘East to the Dawn: The Life of Amelia Earhart’; Dorothy Cochrane, Curator in the Aeronautics Division of the Smithsonian Institution's National Air and Space Museum in Washington; and Susan Ware, author of ‘Still Missing: Amelia Earhart and the Search for Modern Feminism’.Photo: Amelia Earhart in June 1928 (Getty Images)

Nowdays, if you want to find out how long one metre is, you can use a tape measure or, if you are a scientist, you can calculate the distance that light travels in a vacuum in 1/299 792 458 seconds. But how did we decide on what length a metre should be in the first place? To follow the far-from-straight story of the metre Quentin Cooper is joined by Professor Robert Crease, historian of science at Stonybrook University in the USA; Professor Marc Himbert, Scientific director of the Metrology Laboratory at CNAM in Paris; and Dr. Jahnavi Phalkey, historian of contemporary and twentieth century science and technology at King’s College in London.Photo: Lilian Bourgeat's art creation 'Tape Measure', France 2013 (Getty Images)

Alice's Adventures in Wonderland is said to be one of the most quoted books in the world. It has been translated into 174 languages, from Catalan to Zulu, and its fantastical creatures, nonsense words and magical happenings have become part of our shared cultural landscape. Bridget Kendall investigates the story behind Lewis Carroll’s Victorian literary classic and its sequel with Angelika Zirker, Assistant Professor of English Literature at Tübingen University, Germany; Virginie Iché, Associate Professor of English Studies at Paul Valéry University in Montpellier, France, and currently a Visiting Scholar at the University of Texas at Austin; and Robert Douglas-Fairhurst, Professor of English Literature at Oxford University in the UK, and author of ‘The Story of Alice: Lewis Carroll and the Secret History of Wonderland’.Illustration by John Tenniel (Photo by Rischgitz/Getty Images)