: Conservation

We wrote of dust before, for example here and here. The museum is like your home, dust gathers everywhere. Unlike my own house though, the museum is very, very big. The museum's dust problems are correspondingly large.

Last year a student from Cardiff University, Stefan Jarvis, undertook a dust monitoring project in the museum. Stefan was studying for an MSc in Care of Collections, which is a subject very close to my heart. Stefan is also the author of one of our guest blogs. Stefan placed a large number of dust traps around the museum building: in stores and exhibition galleries. You may be familiar with some of the galleries he investigated: our Geology gallery with the dinosaurs, the current “Wriggle” exhibition on worms, the Whale gallery and the Organ gallery where we display some of the largest paintings in the museum.

Collecting dust is really easy: prepare a sampler. Leave it out in a suitable location. Wait. For. Four. Weeks.

Once Stefan had gathered some dust he analysed the samples: he identified each particle under the microscope and determined where they all came from. This is where things started getting really interesting. For while undertaking scientific investigations are often laborious and involves much routine work, the results are often extremely illuminating.

This is what Stefan found:

• More dust accumulates in areas of high traffic (i.e., many people walking past).
• More dust accumulates at low levels (the closer you get to floor level the more dust you will find).
• Dust composition differs between spaces. For example, most dust fibres in a library store are paper fibres, while most fibres in public galleries are textile fibres, hair and skin.
• We found biscuit crumbs on the dust samplers in two galleries. This indicates that food was being consumed in these galleries.

Now, we love having people in the museum. In fact we undertake some of our collection care work during museum opening hours so that you can see what we are up to a lot of the time. Therefore, we are happy to accept that visitors always leave us a little reminder that they have been, in the form of a few dust particles. You can feel a ‘but’ coming on: but we do not encourage the eating of biscuits (or any other foodstuffs) in our galleries. Eating food in our galleries bears the risk of small amounts of food ending up on the floor, in displays, behind cupboards - or, as part of dust. Food encourages the spread of pest insects which, once they have eaten all the available biscuit crumbs, then start munching our collections. This is not something we endorse, because we try to preserve our collections for you to enjoy.

This means you can actually help us preserve the collections - by not eating in the galleries. We will be doing more work on this in the near future, by encouraging visitors to consume food in our fabulous restaurant or cosy cafe, not in galleries. In the meantime, we really do appreciate your cooperation and understanding for our no-food-in-galleries policy.

Find out more about Care of Collections at Amgueddfa Cymru - National Museum Wales here.

The country craft of hedgelaying is being demonstrated at Fagans National History Museum during 2017. Hedgelaying creates a stronger, thicker barrier to keep animals within fields, and provides shelter and shade for them. This year it will be combined with opportunities to try out the craft and the museum provided its first hedge-laying training courses for the public.

Hedgelaying, Pen-y-cae, Brecknockshire, c1936

Creating fields and hedges

From the sixteenth century onwards, vast areas of open land were enclosed and turned into fields for agricultural use. Hedges were planted to prevent sheep and cattle from straying, and to separate grassland from crops. Such hedges also provided shelter, a source of food such as berries, and habitat for wildlife and fauna. Hedges were also cheaper than building and maintaining dry-stone walls.

The craft of hedge laying

Hedges are maintained by laying. Once the trees had grown to a certain height, they were cut and laid horizontally to form a stock-proof barrier. The cut is not made through the branch in order to allow the tree to re-grow. What is created is effectively a living fence. The work is done during the less busy winter months when there is less foliage and the tree will re-grow.

Welsh hedging styles

Methods of laying hedges vary in different parts of Wales. Styles differ according to how the branches are positioned, the use of stakes, and whether binding is used. Hedging is often accompanied by building banks and digging ditches. The hedges being laid this year at St Fagans are in the stake and pleach style from Brecknockshire (Powys).

Stages in laying a hedge, stake and pleach style.

Photographs taken in Sennybridge and Cray, Brecknockshire, 1972-73.

Firstly the hedge is cleared of dead wood and unwanted growth

The branches, known as pleachers, are cut at the base of each stem and bent forward. When cut properly, they should continue to grow.

The pleachers woven between the stakes.

Hazel hetherings along the top bind the stakes and pleachers

Finally the hedge is trimmed and shaped to a uniform height and width.

Gareth Beech

Senior Curator: Rural Economy

Historic Properties Section

History and Archaeology Department

Rock collections in the UK are an asset worth millions of pounds. Many exploration companies drill into the Earth’s crust and extract cores for analysis – often at a cost of around £1,000 per meter of core. These provide the basic information before a commercial case for mining or extraction can be made and form part of the companies’ commercial archives.

Museums also look after collections and many hold large numbers of valuable geological samples. A common misconception is that rocks are stable, they do not decay or get eaten by pests. Which is why fossils, minerals and rocks surely must be easy to look after.

But think of minerals found in caves or mines: not just dark, but also cold and damp. Many hydrated minerals occur here, for example melanterite or halotrichite. Take them out of the mine, put them in a museum store where they are protected and well looked after – and they will dehydrate. Lose water molecules, decay, and are lost.

There are many similar examples. Depending on the mineral species they will take up or lose water molecules, recrystallize into something else, react with air pollutants or oxygen. A bewildering range of chemical processes can lead to the destruction of geological specimens. Fossils are affected, too: lovely pyritised ammonites turn to dust. Many specimens of scientific or historic importance can be lost in this way.

Museums do their best to halt the decay but are hampered in their efforts by many questions yet unanswered. What levels of indoor air pollutants are safe for geological collections and how good do our air filtration systems need to be? At what point do museum conservators need to deal with a specimen damaged by chemical reactions? How do we even monitor collections of tens of thousands of specimens for damage routinely?

These and many other related questions will be investigated in a new research project at National Museum Cardiff. A recent pilot study (manuscript in preparation) demonstrated the complexity of potentially damaging processes in a typical museum store that are thought of usually as benign. Further expertise in the form of academic and industrial partners is now sought to develop the potential for addressing elementary questions of appropriate storage of geological collections.

The knowledge generated by this project will be of wide-ranging interest to cultural institutions and industrial companies alike. Scientific specimens and commercial collections will be kept safe with the set of guidelines and standards which the project will develop. We will have the proper tools to enable us to care for our geological heritage appropriately - whether kept in museums or as commercial assets.

Find out more about Care of Collections at Amgueddfa Cymru - National Museum Wales here.

Our conservation volunteers are helping to get Christmas underway at St Fagans. The first historic building to get the festive treatment was Cilewent Farmhouse originally from Rhaeadr Powys. The display reflects life as it was in the 18th century with most of the furniture dating to 1750. Preparations for Christmas would involve decorating the home with evergreen foliage gathered from the surrounding countryside, such as laurel, ivy, holly and yew. A tradition that has its origins firmly rooted back in our pagan past and continues to this day with the Christmas tree.

The evergreens stand out among the dormant trees in the museum grounds so it didn't take long to gather up enough to prepare the garlands for Cilewent.  We also created a bracket out of 4 sticks of even length (80cm) and to this attached more evergreen foliage and red ribbons. Red berries were very popular, but these dry out and fall off quickly. A recommended technique to help preserve their colour was to store the berries in salt water after picking, we haven't tried this yet, but we'll probably give it a go next year as a flash of red would definitely enhance the overall effect.

The garlands were much bigger than we anticipated and they soon turned into rather unwieldy evergreen snakes, but between us we managed to walk them across the site and secure them to the beams of Cilewent.

If you would like to try this out at home be careful with the holly, it can scratch, not just yourself but furniture and wallpaper as well, so remember to place a barrier of card or fabric between holly and any vulnerable surfaces.

Well, one house done, 11 more to do and only 20 days to Christmas!

This week is Chemistry Week and our Preventive Conservation team got involved. Two local high schools (St Teilo’s Church in Wales High School and Cardiff High School) were invited to participate in a workshop with live demonstrations and hands-on activities.

We organized the workshop in a collection store and one of our analytical laboratories at National Museum Cardiff. Neither space is laid out for large numbers of people and it’s always a bit of a squash. But once we had squeezed the last of the year 12 and 13 students into each room and closed the doors, there was no escaping the exciting world of analytical chemistry.

The students learned about Wales’s largest and most important mineral collection, the challenges of caring for it, and some of the analytical tools that help us: X-Ray diffraction (XRD), gas detection tubes, infrared spectroscopy (IR) and Nuclear Magnetic Resonance (NMR). The XRD is part of the National Museum's own analytical facilities, operated by Tom Cotterell and Amanda Valentine-Baars in the Mineralogy/Petrology section. The other two technologies are covered by the curriculum and the students enjoyed the opportunity to prepare real samples, analyse them and interpret the results. To them, this made the subject a lot more real than just learning about them from books. It was also important that the analyses were undertaken not simply as a method per se, but in the context of answering genuine research questions at the museum.

What does chemistry have to do with the care of collections? We undertake our own research on objects and specimens in the collections, and we collaborate with researchers at universities. In addition, the act of preserving our common heritage often throws up problems, as objects degrade and conservators need to work out why, and how to stop the degradation.

Often we cannot do this on our own, in which case we work with partners to investigate, for example, the corrosivity potential of indoor pollutants and their effect on mineral specimens in storage at National Museum Cardiff. These partners include Cardiff University’s Schools of Chemistry, Engineering and History, Archaeology and Religion (Conservation Department).

One of these collaborations sparked yesterday’s schools engagement project, run in conjunction with the museum's Conservation and Natural Sciences departments and kindly supported and funded by the Royal Society of Chemistry (South East Wales Section). The Royal Society of Chemistry provided an entire bench full of portable analytical equipment for the day, which the society's Education Coordinator, Liam Thomas, set up in the Mineral Store. Because of the interdisciplinary nature of the project, additional support came from Cardiff University’s School of Earth and Ocean Sciences.

Find out more about care of collections at Amgueddfa Cymru - National Museum Wales here.