Our Collections team undertakes a variety of tasks, and last week the team took on their latest project as they undertook a condition audit on a painting in Commissioner’s House. Keep scrolling to see how they got on…
The ceiling painting
The ceiling painting in Commissioner’s House was first commissioned by the Navy Board to be installed in the Great Cabin of HMS ROYAL SOVEREIGN (1st rate ship) in 1701. The painting depicts an assembly of the Roman Gods, where Neptune, the God of the Sea, is crowning Mars, the God of War. The painting is attributed to Thomas Highmore (1660-1720), a specialist in non-figurative decorative painting, and he was the Serjeant-Painter to King William III. A Serjeant-Painter was appointed by the monarch and was responsible for the decoration of royal palaces. It is believed that the figurework was painted by James Thornhill, one of Highmore’s apprentices at the time. Thornhill (circa. 1675-1734) was an English painter who excelled at the large-scale decoration of grand interiors of the Italian Baroque. He later became Serjeant-Painter to King George I.
HMS ROYAL SOVEREIGN was rebuilt in 1728 and broken up at Chatham in 1768, and it can be assumed that the painting has been on display in Commissioner’s House since the 18th century.
The ceiling painting last underwent extensive restoration several decades ago. Due to its location and size, it was likely that both dust and grime had accumulated on its surface, as well as other risks related to deterioration, such as: light damage, chemical and mechanical damage from fluctuating humidity and temperature, as well as pest damage. Our Collections Team therefore carried out a condition audit to be able to lay out a detailed long-term plan to continue preserving the ceiling painting for many more decades to come.
Most paintings can be demounted ahead of a condition audit and moved to a flat surface in a collections workspace. However, as the team had to deal with a ceiling mounted painting, the entire condition audit had to be completed from scaffolding towers, moving them around to gain access to every single angle of the painting. The first, and probably the most important, step was to do a thorough visual investigation. A visual examination can help identify damages such as cracking paint, paint losses, fading colours, surface dirt, old repairs and more.
The use of ultraviolet fluorescence to investigate the painting
Following the visual examination, the team used UV light to examine the painting’s surface. This tool helped detect and identify old repairs and surface coatings, as well as potential insect damage.
The team also used a light meter to measure the amount of light that both surrounds and hits the surface of the ceiling painting. The windows in Commissioner’s House all have UV filters to prevent damage from UV, however it is still important to minimise light levels as many colours and pigments will fade drastically as result of high light levels. The light meter provided the team with several spot readings and by using a mathematical formula the team was able to calculate the approximate annual light exposure for several areas of the ceiling painting. The readings will help the team take steps towards a lower annual light exposure for the ceiling painting.
To conclude the condition audit, the team carried out a light surface clean to remove dust and cobwebs as these likely will cause damage to the surface over time. This was carefully completed using low-suction vacuum cleaners specifically designed for museums and very soft brush heads. Fragile areas were not cleaned using this method in order to prevent loose paint layers coming off. Such areas will need to undergo careful conservation ahead of a surface clean.
With thanks to Karoline Sofie Hennum, Conservator & Helen Brown, Exhibitions and Collections Officer for this behind the scenes blog.