Wolfgang Stoecker is on a mission to explore the cultural meanings of dust, swept up from historic buildings.
Cologne-based artist Stoecker has collected samples of dust from historic buildings across Europe and beyond.
With the help of scientists and an electro-microscope at Augsburg University he has analysed the dust and discovered it contains tiny fossils, dust from the Sahara, pollutants of various kinds and human debris.
Aeolian research, research into dust particles and sediments, is an established branch of geographical study, often concerned with the history and future of climate change, desertification and landscape erosion, but as Wolfgang has discovered, dust can also tell us something about human culture.
Wolfgang has been surprised and delighted by the excitement his requests for dust generate, and the enthusiasm of curators of historic buildings to comply.
John Campbell is the Dean's Verger at Lincoln cathedral.
He received Wolfgang's initial email with some scepticism but it made sense too, because dust is often on his mind as the person responsible for the upkeep of this great building.
He collected two samples for Wolfgang's collection: 'secular' dust near the entrance, where the traffic of feet is greatest, and 'sacred' dust, near the altar, where traces of candles, incense and sacred silverware are to be found.
'I've challenged him to tell me which is which', says John.
'I like to think that the dust here at Lincoln might contain traces of the pilgrims and worshippers who've been coming here over the centuries.
Everyone leaves a trace of themselves behind in the dust'.
Wolfgang Stoecker is an engaging and charismatic host in this thought-provoking and witty documentary.