Does the land still inspire artists who no longer find traditional oil painting relevant? Glen Onwin , an Edinburgh artist, works in close communion with the natural world but doesn't depict nature. Instead, he works with its materials and processes - mud, juices and salt crystals.
Scientist and art historian Professor Martin Kemp of St Andrew 's University walks with him across the Dunbar Salt Marshes on Scotland's east coast and discusses the points at which art, alchemy and science come together in his work.