Royal
Incorporation of
Architects in
Scotland

The Lorimer & Matthew Collection, catalogued and conserved as part of the Scottish Architects' Papers Preservation Project, consists of 35,220 items, which reflect Lorimer's position as one of Scotland's leading architects of the late 19th and early 20th centuries. The collection comprises 33,000 drawings and 2,200 photographs ranging in date from the 1890s to the 1960s. The main proportion of photographs in the Collection reflect Lorimer's work during the 1920s as a designer of war memorials, the largest of which, and perhaps his best known work, was the Scottish National War Memorial, Edinburgh Castle (c.1919-27). In 2004, a small group of photographs from the Collection were selected for conservation. Their identification, conservation requirements, condition and subsequent treatment were recorded as follows:

View of Royal Palace showing pencil annotations to tower, Edinburgh Castle, c.1919-23, from the Lorimer & Matthew Collection. LOR/E/122/83/8

Gelatin Developing Out Prints (DOPs) were first produced in the late 1870s, with gaslight paper (where the paper was exposed under gas light not natural light) being one of the first types. By the 1920s, Printing Out Prints had almost ceased production with DOPs being favoured for creating an image of greater contrast.

Silver Gelatin DOPs have a three layer structure:

Each item displayed similar conservation problems and were therefore treated in a similar manner. Treatments were conducted primarily in order to stabilise the objects and make them accessible to the public, but also improve their aesthetic and historical integrity.

View of Old Barracks, Edinburgh Castle, before reconstruction, c.1919-23, from the Lorimer & Matthew Collection. LOR/E/122/83/5

Overall, the photographs, mounted on to board with adhesive tape, were considered to be in relatively poor condition. The objects had suffered mostly from exposure to surface dirt, abrasion and structural damage, resulting in chemical and physical degradation. Inadequate storage, excessive handling during their lifetime and poor quality, non-archival mount boards were the major contributing factors to the deteriorated state of the supports, particularly the secondary mount boards.

Primary Supports: Photographs

Physical Deterioration:
· Overall surface dirt in the form of dirt and dust particulates is apparent, most probably caused from poor storage and handling.
· Localised staining: finger prints, rust stains.
· Fair overall structural condition. Evidence of localised abrasions. Minimal evidence of tearing, cracking or loss.

Chemical Deterioration:
Oxidation
Oxidation is a process whereby changes in the silver occur. It is identifiable by the appearance of a blue-silver metallic sheen, particularly evident in the darker areas of the image. More commonly known as silver mirroring, this phenomenon typically begins from the outer edges of the image and moves in towards the centre. It is especially evident when viewed in raking light. Air and moisture are all causes of silver mirroring as are hygroscopic mounting adhesives. Silver mirroring is especially evident in the darker areas of the photographs. Due to the extreme sensitivity of silver gelatin prints to moisture, it is inadvisable to carry out wet conservation treatments. They are also very prone to mould growth and therefore moisture should be eliminated.

Silver Sulphiding
There is limited evidence of silver sulphiding having occurred in these photographs, which is usually characterised by a yellowing of the image or localised spotting. Sulphiding occurs through insufficient washing of the fixative and the presence of atmospheric pollutants such as sulphiding gases.

Secondary Supports: Mount Boards
All photographs are adhered to poor quality laminate boards that display signs of deterioration in the form of discolouration, weakening and splitting.

Physical Deterioration:
· Overall surface dirt in the form of dirt and dust particulates, most probably caused from poor storage and handling.
· Localised staining: finger prints, rust stains.
· Extensive structural deterioration; splitting of boards, cracking, tearing, abrasions, losses, also a result of poor storage and handling.

Chemical Deterioration:
Overall discolouration of the boards is evident, appearing as a light yellow-brown colour, particularly in the centre of the laminate structure where a more burnt-orange colour was noticeable.
The discolouration was most likely to have been caused by chemical deterioration processes, oxidation and hydrolytic degradation.

View of the barracks, Edinburgh Castle, before Lorimer’s reconstruction, c.1919-23, from the Lorimer & Matthew Collection. LOR/E/122/83/145

It was decided to carry out only minimal conservation treatment on these photographs as due to their hygroscopic nature further degradation could result from contact with moisture.
The following treatments were therefore considered:

· Removal/reduction of surface dirt on primary and secondary supports
· Reduction of localised stains and accretions on both supports
· Structural repair of secondary support boards to render them more stable
· Re-housing using archival quality materials.
· Storage in environmentally controlled conditions.

View showing East side of the barracks, Edinburgh Castle, before Lorimer’s reconstruction, c.1919-23, from the Lorimer & Matthew Collection. LOR/E/122/83/2

Surface Cleaning: a mechanical, dry cleaning process, using a soft Hake brush, chemical sponge (used only on the mount boards as the sponges are known to contain traces of sulphur) and grated, Plastic Staedtler Mars Eraser®. Due to the photograph’s inherently delicate surface, the eraser was only lightly rubbed over the surface. The dry cleaning successfully removed much of the surface dirt resulting in visually clearer images and aesthetically pleasing objects as can be seen in the before and after treatment photographs.

Reduction of Stains/Accretions: Localised rust stains and spots of dirt were reduced by mechanical means, using a scalpel, to gently pare down the mark.

Structural Repair: Carried out only on the secondary support boards, a dry consistency wheat starch paste was used to adhere split and torn areas of the boards. Using a small brush, the adhesive was applied in between the board’s layers and then weighted until dry. The photograph showing the North side of the barracks before reconstruction (LOR/E/122/83/6) had a central, vertical split running through both supports. It had created severe weakening of both supports causing them to fold inwards. A repair was attached to the verso of the board, along the split, using wheat starch paste and a Japanese Kozo Repair Tissue. The repair successfully re-inforced the supports, preventing them from further movement.

View showing North side of the barracks, Edinburgh Castle, before Lorimer’s reconstruction, c.1919-23, from the Lorimer & Matthew Collection. LOR/E/122/83/6

The large laminate board on which photographs of six different war memorials were mounted, was covered with rough textured thin, black paper and was in extremely poor condition, with corners missing and severe splitting. The greatest area of loss in the top left corner was re-built using archival quality mount board and toned to be in keeping with the rest of the support.

War Memorials at St John’s Church, Smith Square, Westminster, London; Carlisle Cathedral; Eton College; Christ Church Cathedral, Oxford; St Andrew’s Church, Glass, Aberdeenshire; and St Andrew’s Parish Church, Golspie, Sutherland, c.1920, from the Lorimer & Matthew Collection. LOR/M/42/1/1

Storage: Sulphur free materials are required to house photographic works in order to avoid further chemical deterioration from silver sulphiding. Materials should also have a neutral pH value; 6.5-7.5, as alkaline conditions (ie; pH8-14) can affect the image and binder in some instances. The conserved photographs were inserted into Melinex® sleeves and then placed inside a new Solander Box. They are housed in a controlled environment, free from atmospheric pollutants, in cold storage conditions where temperature and relative humidity are monitored.

The images above show a small selection of the photographs and drawings from our Collections which can be consulted in the public search room from Monday to Friday, 9:30am to 4:30pm. Click on an image to view the full-size version. Prints of all images can be obtained by contacting RCAHMS directly at info@rcahms.gov.uk quoting the name of the site or building, the SC number, the size and nature of each image required. A price list of services for photographs, digital images and other copies can be found under the price list page.