JAIC 2004, Volume 43, Number 3, Article 3 (pp. 237 to 254)
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Journal of the American Institute for Conservation
JAIC 2004, Volume 43, Number 3, Article 3 (pp. 237 to 254)




There is some evidence in American artist's manuals that the writers of these treatises were beginning, by the late 19th century, to tell painters for the first time that a thin varnish looked better than a thick varnish. Early and mid-19th-century American sources tend not to comment on the recommended thickness of varnish, or, if they do, it is only to say that two or three thin coats are better than one thick coat—the implication being that a relatively heavy layer of varnish was the desired result, or at least an accepted result.2 By the second half of the 19th century, painters in Europe occasionally expressed a preference for thin varnishes. For example, Edouard Manet (1832–1883) gave instructions for one of his paintings to be varnished “very lightly” in the 1860s (Swicklick 1993, 166), and John Singer Sargent (1856–1925) had a similar opinion in favor of thin varnishes as opposed to thick ones in 1881 (Charteris 1927, 55). The Impressionist aesthetic may have augmented this trend, a thin layer of varnish perhaps being seen as a compromise between a thick varnish layer and no varnish at all. Thinner varnish layers might also have been preferred because they would allow textured paint surfaces to remain more visible, in contrast to the smooth, glossy surfaces associated with academic painters. (See, for instance, Swicklick 1993, 161, on Adolphe-William Bouguereau's [1825–1905] use of varnish as an intermediate layer and as a paint additive to achieve his famously smooth surfaces.)

An example of the new preference for thin varnish is found in the 1888 instruction book written by the American Mary Louise McLaughlin, which speaks in excited terms about the “great change” that occurred during the previous decade with the advent of Impressionism. McLaughlin wrote: “A heavy coating of varnish is neither desirable for the artistic effect nor for the preservation of the picture” (McLaughlin 1888, 109).

A decade later, in 1898, the instruction book by Daniel Burleigh Parkhurst (who, as described above, was familiar with and presumably had some sympathy toward both French and American Impressionism) stated that if a painter chose to use varnish, it “should not be flowed on” but should be “as thinly distributed as will serve the purpose” (Parkhurst 1898, 63).

Even Abendschein, the author of the previously cited quotation that criticizes “dead, dull, lackluster” surfaces, goes on to admit that “on the other hand, some of the paintings in our museums and private galleries are heavy with varnish. There is a beautiful medium between both extremes” (Abendschein [1906]1909, 63).

A later source of information is Martin Fischer's book The Permanent Palette, in which a number of artists were interviewed about their techniques. Two painters who were still working in an Impressionistic style in 1930 indicated, in their responses, that they varnished thinly. Wilson Irvine (1869–1936) said that he used “very little” mastic varnish, and Dixie Selden (1871–1935) said that she used mastic varnish “thinned half, or even more, with turpentine” (quoted in Fischer 1930, 93, 95).

The thickness or thinness of a varnish can sometimes make a surprising difference in the appearance of an Impressionist painting. For example, the authors treated a painting by Childe Hassam (Isles of Shoals, 1908, private collection) that had a recently applied, fairly thick layer of varnish (fig. 1). Both owner and conservators felt that a large dark area in the depiction of the surface of the sea looked heavy and out of balance with the rest of the picture. When the recently applied varnish was removed, the dark area was very matte compared to the rest of the picture. Since Hassam varnished at least some of his paintings (see sec. 6.1 below), the painting was revarnished, but with a much thinner coating that allowed some of the differences of gloss in the artist's paint to show more clearly. The result was that the dark area was slightly less saturated and appeared somewhat lighter in value relative to the rest of the painting, which kept the area from looking too dark and too heavy. The Hassam is a fairly unusual case, but in this instance the thinner varnish layer improved the appearance of the painting to a noticeable degree.

Fig. 1. Childe Hassam, Isles of Shoals, 1908, oil on canvas, 63.5 76.2 cm (25 30 in.). Private collection. After treatment

Copyright 2004 American Institution for Conservation of Historic & Artistic Works