Written by Claire Dean, Curatorial Assistant at Tullie House Museum and Art Gallery, Carlisle, and MA Preventive Conservation student at Northumbria University.

In many old dioramas, material mysteries abound. As a Curatorial Assistant at Tullie House, I’ve encountered a tree trunk made from a Robinson’s fruit juice box, a fake roof that contained fibrous signs of asbestos, and a hodgepodge of unidentifiable paints and old plastics. The museum’s new-in-post Biodiversity Curator discovered pests thriving amongst the real vegetation and a 30-year-old slice of bread in a garden scene.

Dioramas aim to create the illusion of real habitats for their taxidermy inhabitants, and they use a huge range of materials to do so. After decades of neglect and destruction there is now wider recognition that habitat dioramas can instil a sense of wonder in visitors that no amount of digital wizardry can replace. Through my dissertation research for an MA in Preventive Conservation at Northumbria University, I wanted to find out more about what materials have been used in dioramas over time, how these might impact the preservation of specimens, and what we can do to better protect the dioramas that remain. I put a call out to ask, ‘What’s in your dioramas?’ through an online survey and received 30 responses from people with experience in a range of different sized institutions and private practice.

The majority of survey responses came from US and UK, with responses also received from Australia, New Zealand, Canada and the Netherlands. There were a lot of similarities in the core materials reported from older dioramas. This seems to reflect the way the diorama trend spread around the world in the late 19^th and early 20^th centuries, and the way skills were passed on by merchant naturalists and in studios, and the popularity of manuals like Montagu Browne’s Artistic and Scientific Taxidermy and Modelling (1896).

Paint, wood, stones, plaster, taxidermy, sand, real plant materials (both painted and unpainted) and glass were the materials most commonly reported. This combination of natural and manufactured materials creates complex composite installations that nearly always showcase biological specimens, in some cases of species that are endangered or extinct. The taxidermy mounts are also composite objects in themselves. Many of their materials remain hidden until ageing skins split revealing the innards. Taxidermist Jazmine Miles Long is undertaking vital research into the impact of materials used on the deterioration of specimens. The irreplaceability of natural science specimens may not have been a prime concern of 19^th century diorama makers, but for those of us caring for, or creating, dioramas now it is a huge responsibility that needs to inform material choices. In a sealed display case, VOCs from materials like wood, varnishes, and some paints, adhesives and plastics can accumulate and accelerate the deterioration of specimens.

The enduring popularity of real plant materials in dioramas is intriguing given that accounts of the speed of their deterioration and attractiveness to pests are recorded from the 19^th century. A desire for authenticity may play a role in this, but also perhaps convenience, given crafting foreground elements takes considerable resources. The survey responses show a decline in the use of traditional materials like wax and clay in dioramas. The reduction of artists and craftspeople in the employment of museums from the mid-20^th century onwards has meant skills and knowledge has been lost. Contemporary botanical wax artist, Annette Marie Townsend, needed to teach herself how to create models using the archives and notebooks of early botanical artists at National Museum Wales.

Plastics have proliferated in respondents’ dioramas over time. For dioramas made before 1990, 41% contain plastics, including early plastics like cellulose acetate, which is known to release harmful acidic vapours. More than 80% of post-1990 dioramas include plastics. In some cases, these were identified as inert plastics, but polyurethane and polystyrene were also listed, and in most responses the plastics were unidentified. The lack of information on additives in commercial plastics means potential impacts can’t easily be assessed. The increasing popularity of 3D printed models in displays is also concerning given the potential impact on artefacts the degradation of plastics in museum cases may have.

As well as more familiar materials, dioramas are almost always home to the unexpected. As one respondent put it, ‘I’m not sure if I would be surprised by anything in a diorama’. Discoveries reported included seeds that later sprouted in an unemptied water-cannister vacuum cleaner, and tar balls that were used to make very realistic sheep faeces. There was also lots of evidence of diorama makers using and reusing whatever was to hand from ‘an old chair inside the groundwork of an Andean condor case’, to rockwork constructed from packing cases, which was ‘probably used to transport specimens and other goods on the collector’s many safaris across the African continent!’.

The survey showed preventive conservation is a major consideration for respondents who are caring for dioramas or planning new ones. Off-gassing, attractiveness to pests, and health and safety were the most significant considerations. Cost was also a consideration for more than half of respondents. In an era of ever-shrinking budgets, one person noted that, ‘Cost is the main barrier to effective preventive conservation’.

A more surprising finding given the role dioramas play in environmental education, was that sustainability was not a consideration for more than half of respondents. My own experiments with making diorama elements offer some insights into a potential reason for this. Aiming for sustainability, I’ve made use of scraps and off-cuts of conservation safe materials, but I’ve been over-reliant on inert products derived from petrochemicals like Plastazote and archival PVA. Conservation safe materials shouldn’t come at a significant cost to the environment, and this is an area where more research is needed.

Perhaps one of the most important findings from the research is how common a lack of documentation is. This causes ongoing issues for the care of dioramas. In the 1930s, Tullie House Curator Ernest Blezard constructed many of the museum’s renowned bird boxes. He left detailed field notes from his ornithological surveys, but not a single note relating to how he constructed the dioramas, or what pesticides he used to protect them. Without access to expensive equipment, it’s tricky to identify materials caked in paint and varnish, or to know if the coatings themselves could cause harm to the specimens or the staff who work with them.

So, one of the most important things we can do (and the bonus is it costs nothing but a small amount of time) is not add to the museum’s material mysteries. We need to ensure we’re documenting anything and everything we use in the care and construction of dioramas in a future-proof way. 

N.B. If you’re interested in reading the dissertation, or just chatting about dioramas in general, please do get in touch at claire.dean@tulliehouse.org. Thanks very much to everyone who responded to the survey for sharing their knowledge and insights. Thanks also to my tutors at Northumbria University and Wednesday Batchelor, Biodiversity Curator at Tullie House, for support with this research.