*Blogger is having difficulties tonight. I cannot edit my writing well - no hyperlinks or bolding, etc.*
I have a long commute three days a week and I find listening to podcasts a good way to fill the time.
On such podcast is BBC4's "In our time". www.bbc.co.uk/radio4/history/inourtime/
Despite the title, the speakers mostly discuss historic events (I think the title refers to how the subjects are researched and understood 'in our time'). The most recent episode questioned how or why China was far and away the world leader in science and technology from the twelth century to only a few hundred years ago. European technology only pulled ahead in the nineteenth century.
One item of discussion was gunpowder. The Chinese understood how to use it as a propellent in fireworks but the main reason it was made was as part of Chinese alchemy and medicine. Once the secret of gunpowder reached Europe, its usefulness, um, exploded.
Also mentioned in some detail were printing presses and ceramics. Although Korea itself is not mentioned, the parrellels are clear.
"In Our Time", as a download, is available for a week. After that, you can still listen as a stream but not a download.