After an oil painting is thoroughly dry the surface can be covered with a layer of varnish. Varnish gives the painting a protective layer as well as restores the wet richness to the colors (most paints tend to dull or turn matt as they dry). Traditional varnishes are made from natural tree resins such as dammar or mastic (there is a bottle labeled “MASTIC” in The Fox Chase). The resins are mixed with a solvent such as turpentine and applied to the painting. When the solvents evaporate, a thin layer of glossy resin remains on top. Natural resins have a slight yellow appearance, which certain schools of art appreciate as it adds to the tone and makes the paintings look somewhat aged. Today, crystal clear varnishes are available. These are made from acrylic resins, which act like a plastic.

“NOTICE !! UNDER NO CIRCUMSTANCES should VARNISH or other mediums be applied to this canvas — as they will change certain ‘values’ — and thereby ruin it.”

~ Artist Willard Metcalf on the back of his painting
Benediction (1920), currently in a private collection

To varnish or not to varnish a finished painting was a major ideological difference between the Tonalists and the Impressionists, both in Old Lyme and elsewhere. Ranger knew that a final coat of varnish locked in all the colors, offered a protective surface, and made his paint shimmer like stained glass. It also made a connection with the tradition of the Old Masters, who were known to finish their paintings with a coat of varnish—much of which yellowed and darkened over the centuries changing their appearance entirely. He felt so strongly about this that he offered this warning in one of his Art-Talks: “If any one at any future time uses a solvent on one of my pictures, and dares to remove a glaze without knowing how to put it back, he will be committing an unpardonable violence against me and my wishes.”

The Impressionists on the other hand did not want that final layer of gloss that might yellow with time. Instead, it was believed that they wanted their canvases to look modern, fresh, and new—the antithesis to the Old Masters. Willard Metcalf printed warnings on the reverse of some of his canvases. He begins somewhat agitated on a painting from 1917-18 with “DO NOT VARNISH W L M” but several years and several canvases later rachets up to “NOTICE !! UNDER NO CIRCUMSTANCES should VARNISH or other mediums be applied to this canvas—as they will change certain ‘values’—and thereby  ruin it. / W.L.M.”

More recently, however, art conservators Lance Mayer and Gay Myers have been able to study the actual layers of pigment and varnish in both French and American paintings to discover that most artists either varnished or didn’t varnish on a case by case basis. How they wanted their final product to look determined how they treated the finished painting. Although many American Impressionist paintings hang in museums unvarnished, there are many with glossy, dazzling surfaces. Indeed, all of the panels in the Griswold dining room were varnished at regular intervals by the artists themselves, including those along the top which were painted first by artists affiliated with the Tonalists, as well as those along the bottom painted by Impressionists. Childe Hassam, who was the leading proponent of Impressionism in America wrote to his dealer about his famous flag paintings: “I will not let them go anywhere until I have varnished them all this fall or early winter.”

During the mid 1980s, the art conservators Lance Mayer and Gay Myers reviewed each of the panels in the dining room to determine their condition. Their analysis provides insight into both the working methods of the artists and the changes the panels have undergone over time.

According to the examination report for the Woodhall Adams panel: “The support is a 1.3 cm (1/2”) thick piece of softwood, which has been coated with a thin paint and resin layer on the reverse. On the front, the panel has been coated with a dark mahogany stain, followed by layers of an oil-type paint, freely applied with much low impasto. There is a thin natural resin varnish coating. Some areas, especially in the foreground, which look at first like abrasion, actually appear to be the result of dark glazes which are applied very thinly and allow textures beneath to party show through. The varnish has discolored to a dark yellow color, and has attracted dark grime particles. Removing the discolored varnish and grime will make the painting dramatically brighter.” The panels were each treated in the manner suggested by the art conservators.

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