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The Map of the
Counties of Stormont, Dundas, Glengarry, Prescott, and Russell, from the
collection of the Chesterville and District Historical Society, received
conservation treatment at the Canadian Conservation Institute, Department of
Canadian Heritage, Ottawa, between July 1989 and February 1991.
The map is printed in four sections on poor-quality wood pulp paper. It was
mounted on a linen backing, hung from display rods at the top and bottom, and
coated with a thick varnish (figure 1). Originally, the varnish was applied to
the map to protect its surface and to enhance its aesthetic appearance.
However, as the map aged, the varnish caused severe degradation of the paper.
Over the years, the varnish became darkened and brittle, and as it was unrolled
and rolled for storage the map became torn and split. Some of the damaged areas
had been repaired with pressure-sensitive tape. By the time the map arrived at
CCI, the adhesive on the tape had become dry and the tape itself was lifting
from the surface. This had resulted in brown adhesive stains and in skinning of
the surface layers of the paper. Other damage to the map included water stains,
a missing dowel from the top of the map, and reinforcement of the cloth backing
with brown paper grocery bags.
The conservation treatment was complicated by the map's large size--157 cm x
160 cm (almost six feet square)--and the need to remove the varnish without
losing any of the colour or information on the map. Various varnish-removal
techniques were tested on small areas of the map, and a cross-section analysis
was made of the tested areas. Finally, a treatment technique used at the
Northeast Document Conservation Center (U.S.A.) was chosen to remove the
varnish. This entailed spraying a mixture of solvents, called a reforming
solvent, onto the varnished surface of the map (figure 3). The action of the
solvent mixture on the varnish made the varnish easier to remove.
In order to wash the map thoroughly, a screen had to be constructed to
support the map and keep it flat while allowing water to circulate above and
below it. The screen was made up of three layers: an aluminium grid to keep the
large screen rigid, a network of PVC plumbing pipes of 1.25 cm in diameter to
circulate the water, and a layer of "egg- crate" grating on which to
support the map. The map was washed in a tray of water to remove the varnish
layer and any other impurities. The map was supported on a cut piece of PeCap
(a woven polyester monofilament) fabric laid on the screen during washing
(figure 4). Varnish removal was aided by the use of swabs, blotters, and soft
brushes. After two preliminary washes, the cloth backing was peeled off (figure
5) and the map was given a final wash. The map was then ready for its new
backing.
A large table was covered with a layer of Terylene (a polyester release
material). To this, heavy linen and Japanese paper were applied with wheat
starch paste. The map was rolled up on a cardboard carpet tube and supported
above the table on photographic light stands on casters (figure 6 ). A thin
film of paste was spread over the surface of the Japanese paper backing. The
light stands were moved along beside the table as the map was unrolled onto the
new backing (figure 7) using large, dry paste brushes to assure smooth
application and good contact (figure 8). Once the map was completely dry, the
holes and damaged areas were infilled with Aiko's old gold #331 Japanese paper.
Pieces were cut to shape and applied to the edges of the map with wheat starch
paste (figure 9). The same Japanese paper was disintegrated in a blender for
pulp fills in small cracks and missing areas within the map. To improve the
aesthetic appearance, watercolour paints were used to inpaint the areas that
were cracked or skinned. The map was then trimmed and black tape was sewn along
the right and left edges. The Furniture and Wooden Objects Section of CCI made
a replica of the missing dowel, which was painted with a black latex paint. The
top and bottom dowels were attached to the map through cloth tape using a
series of brass cup washers and screws.
A ridged support for mounting the map was constructed using 3 mm Luan
Mahogany plywood door skins fastened to a pine frame. A layer of Marvelseal 360
(a foil composed of nylon, aluminum, and polyethylene) was ironed onto all the
surfaces of the support, making it impervious to degradative acids, vapours,
and moisture. Linen fabric was washed thoroughly and, while slightly damp, was
stretched onto the support over an inner layer of polyester batting and stapled
in place). The map was mounted onto the support by attaching woven binding tape
to the top rod and elastic to the bottom rod and then fastening them to the
pine frame (figure 2). The elastic attachment will allow some movement if the
map expands or contracts while on display. A pine frame was constructed to
house the Map of Five Counties so that it could be incorporated into a
partition wall in the Chesterville Museum.
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