LIKE many other 19th-century American artists, Eastman Johnson (1824-1906) began as a portraitist: before the invention of the camera, even an artist without training or reputation could earn his bread and butter by painting likenesses, and Johnson was more than usually talented. But he was also ambitious. Portraiture seemed to be little more than hackwork, and Johnson aspired to paint pictures that would show country people and occupations in a realistic and yet pleasing way. He studied in Europe from 1849 to 1855, and almost as soon as he returned home began trying for a European-style masterpiece on an American theme. His first subject could hardly have been more native: He sketched Chippewa Indians on two summer visits to Wisconsin. As the years passed, Johnson became a highly regarded painter of everyday life, but the masterpiece he longed for continued to elude him until 1880, when he completed ``The Cranberry Harvest, Island of Nantucket.''
Johnson has pictorially identified the island by including a windmill. Nantucket was one of the few places in New England where windmills existed as late as 1880. At upper left are sailing ships and a lighthouse, which refer to the town's prosperous past as a whaling port. The spires of real churches can be recognized in the painting.
Many viewers must have en- joyed the subject alone: Work hardly different from play, set against a background of historic New England. Nostalgia for the rural past was as salable then as it is now. But it was form, not subject, that made ``The Cranberry Harvest'' Eastman Johnson's crowning achievement.
The painting includes more than 40 figures, most of them stooped over to gather cranberries. One woman stands and looks to the right: She is the picture's center of interest, but we have no idea what she is looking at or waiting for. The cranberry pickers seem almost accidentally grouped, as if they were real workers rather than an artist's models. Johnson labored for months to make the final composition exactly right without being too obviously artful.
`THE Cranberry Harvest'' is remarkable for its quality of light. The afternoon sun creates brilliant splashes of color, together with areas of deep shadow. We know Johnson did almost 20 studies for ``The Cranberry Pickers'' and that he wrestled with it through the autumn and winter of 1879, but it looks as if it had been painted rapidly in the open air.
This combination of effort and spontaneity, together with Johnson's desire to create a grand composition that would bring together many human figures, may be traced in part to his study with Thomas Couture in Paris. Couture was himself a successful painter of large-scale, multifigured compositions. Although he taught his students to emulate classical art in form, he also advised them to use subject matter presented by daily life: ``Be Parisians, as they of Athens were Athenians,'' he would say, and Johnson adapted that precept to his own situation as a resident of Nantucket.
At a time when fastidious surface effects were highly valued, Couture developed a technique in which a quick oil sketch could be incorporated into a finished work of art; the result was seemingly spontaneous painting in well-arranged compositions.
JOHNSON took these principles home with him and applied them to the American scene. After his abortive studies of the Chippewa, he went to Maine five times to gather material for a large-scale painting of maple-sugaring. Successful as he was with smaller paintings, he seems never to have been fully satisfied with his attempts at the monumental until ``The Cranberry Pickers.''
With that painting his self-appointed task was finished. For the rest of his active career he painted portraits, and never again tried the multifigured outdoor scenes that appear to have obsessed him for the preceding two decades.
Johnson was a transitional artist, and ``The Cranberry Harvest'' is a transitional work. It looks back to the academic training and sentimental subjects that were popular in Johnson's youth, but also forward to the spontaneous treatment of light and color pioneered by the Impressionists and other modern artists. In 1880, it was hung in the place of honor at the annual show of the National Academy of Design. More than a century later it is still considered one of the outstanding achievements of American painting.
An exhibition that includes ``The Cranberry Harvest, Island of Nantucket'' and 13 related paintings and oil sketches by Eastman Johnson can be seen at the Yale University Art Gallery, in New Haven, Conn., from Sept. 29 through Dec. 9. It was organized by the Timken Art Gallery, in San Diego.