ROCKLAND, ME. -- Celebrating its 50th anniversary with the opening this summer of its Center for the Wyeth Family in Maine, the Farnsworth Art Museum in tiny Rockland has evolved into a major presence on the national art scene. Opened in 1948 with funds from a reclusive local spinster, the Farnsworth, with its fine holdings of Maine art, has long enjoyed a reputation as a jewel of a regional museum. Its expansion doubles its space and stature.

The Farnsworth's new $5 million facilities comprise enormous galleries in a converted church adjacent to the original museum building and a study center in a wing completed in June. They will eventually house 4,500 objects relating to the Maine art of N.C., Andrew and Jamie Wyeth, including 75 major paintings and hundreds of watercolors, drawings, photographs and archival materials, given by Andrew Wyeth and his wife, Betsy. The Farnsworth beat out the National Gallery of Art, among others, for the prestigious trove.

Continuous summer residents of the area since the 1920s, three generations of Wyeths have gained inspiration from the rugged coast, scenic islands, diverse landscape and resilient inhabitants of mid-coast Maine. The family has had a long and warm association with the Farnsworth, and participated actively in planning the expanded facilities.

The center will be a boon to Wyeth fans and art historians. "For scholars," says Farnsworth director Christopher Crosman, "the material...in the Center should contribute to...a much better understanding of Wyeth's art. For the general public our exhibitions...should be an eye-opener, revealing aspects of the Wyeths' art that have rarely been talked about, and never...addressed in this much depth." The museum also plans a major expansion of its art education program, especially for Maine school students.

The widely-publicized Wyeth Center opening, accompanied by a large and attractive Wyeth exhibition, have resulted in doubled attendance and an enormous increase in shop sales, according to Farnsworth officials. Meanwhile, the museum's expansion and growing reputation have attracted galleries and related shops to Rockland, encouraged a proliferation of restaurants and bed and breakfasts, and generally boosted the economy of a community of 8,000 that had slumped in recent years. Local business people marvel at the number of visitors frequenting their places wearing Farnsworth admission stickers.

That the museum exists at all verges on the miraculous. It is a testament to the vision and generosity of a frugal, astute woman who virtually shunned the community but ended up putting it on the map. Daughter of William A. Farnsworth, Rockland's leading businessman, Lucy Farnsworth parlayed proceeds from her father's will into $1.3 million by the time she died in 1935 at the age of 97. The town was astounded when it was revealed that her will directed that the money be used to build an art museum in her father's honor. She also bequeathed the Farnsworth Homestead -- a large, pristine Victorian house on the museum grounds -- which is open for tours. As Farnsworth board chairman John S. Ames III observed at 50th anniversary ceremonies, "What a great legacy, a reclusive lady who made possible a museum and home accessible and open to the public."

Thanks to careful purchases in the 1940s by an agent appointed by the Boston bank that executed Lucy Farnsworth's will, the museum had built up an admirable trove of Maine-related artwork by the time it opened its doors in 1948. In addition to early purchases of work by Andrew Wyeth and later N.C. and Jamie, astute acquisitions over the years since then have given the Farnsworth a collection of enviable breadth and, in some cases, depth in American art.

The permanent collection of 8,000 objects includes works by Gilbert Stuart, Thomas Sully, Thomas Cole, Fitz Hugh Lane, Eastman Johnson, Winslow Homer, Thomas Eakins, John Twachtman, Maurice Prendergast, Childe Hassam, Robert Henri, Marsden Hartley, John Marin, George Bellows, Edward Hopper, Rockwell Kent and Milton Avery.

After the Whitney Museum of American Art, the museum boasts the largest holdings of sculpture and paintings by Louise Nevelson, who grew up in Rockland. Among prominent contemporary Maine artists represented at the Farnsworth are Richard Estes, Robert Indiana, Alex Katz, William Wegman and Neil Welliver. The museum's holdings were significantly augmented in the last year by a major bequest of 70 Maine works from philanthropist Elizabeth B. Noyce.

In keeping with its expanded space and aspirations, the Farnsworth this summer has mounted the largest and most ambitious exhibition in its history, "Wondrous Strange; Pyle, Wyeth, Wyeth & Wyeth." Conceived by Betsy James Wyeth and selected with the help of her husband, Andrew and son Jamie, the show brings together over 100 major works of art from public and private collections all over the world. The exhibition, which closes November 8, traces the influence on all three generations of Wyeths of Howard Pyle, the so-called father of American illustration, who was N.C. Wyeth's teacher.

The show was organized jointly with the Delaware Art Museum in Wilmington, where it will be on view December 10 to February 21, 1999.

A full-color, 168-page catalogue, with essays by Farnsworth director Crosman and chief curator Susan C. Larsen, Delaware Art Museum director Stephen T. Bruni, Betsy James Wyeth, art critic Theodore R. Wolff and David Michaelis, author of a forthcoming biography of N.C. Wyeth, accompanies the exhibition.

Providing, as Crosman puts it, a "once-in-a-lifetime opportunity to focus on Pyle's relationship to all three generations of Wyeths in an expansive and in-depth manner," the show spreads throughout the museum's main floor galleries and the new Wyeth Center galleries in the former church and into the Study Center wing. As a result, little of the outstanding permanent collection is on view this summer. Those works will return to the museum's walls after November 8, along with smaller, special exhibitions that have long been features of the Farnsworth's schedule.

The museum did set aside some space this summer for a superb, focused display of some 20 Maine works by realist titan George Bellows and Impressionist master Frank W. Benson. "Bellows and Benson: Reality and the Dream" (through November 8) showcases Bellows' depictions of shipbuilding in Camden and fishermen on Maine islands, painted between 1911 and 1916, and Benson's sun-splashed views of his family at leisure at their longtime summer place on nearby North Haven Island, created between 1901 and 1923. Both are superb painters. The show offers interesting contrasts between Bellows' concentration on Mainers toiling amidst the natural beauty of sea, land and mountains and Benson's focus on the idyllic life of summer people enjoying themselves under sunny skies surrounded by water, hills and benign clouds.

Exploring how elements of fantasy and drama that infuse works of the Wyeths emanated from Pyle, a great teacher and accomplished artist in his own right, "Wondrous Strange" takes viewers through dangerous dungeons and dark forests, on storm-tossed seas and onto desert island beaches, and to familiar but somehow transformed and magical landscapes, islands and lighthouses of midcoast Maine. The common thread linking the art is a sense of wonder, mystery, emotion and excitement. (The phrase "wondrous strange," uttered by Horatio in Shakespeare's "Hamlet," is an expression of strong approval in the Wyeth family.)

The man who set these artistic, cross-generational affinities in motion, Howard Pyle (1853-1911), was a magnetic personality with a flair for instilling in his pupils concepts of dramatic action and historical accuracy. As underscored by "History and Romance: Works by Howard Pyle from the Brokaw Family Collection," an exhibition earlier this year at the Brandywine River Museum in Chadds Ford, Penn., Pyle was an artist of superb and diverse skills who believed fervently in the power and importance of illustration as a uniquely American form of art.

Illustrating books and articles on subjects ranging from the Middle Ages and American history to scenes evoking adventure, notably involving pirates, Pyle stressed accuracy, detail and composition to make texts come alive. This is exemplified by "Kidd on the Deck of the `Adventure Galley,'" a 1902 watercolor in the exhibition.

Pyle's deep commitment to educating future illustrators led to his teaching courses -- in Wilmington and summers in Chadds Ford -- that launched a number of significant illustrators. His most gifted protege, N.C. Wyeth (1882-1945), was a rugged New Englander who quickly grasped Pyle's approaches to art and adopted his romantic sensibility. Wyeth achieved early success as an illustrator and settled in Chadds Ford, with a summer place in Port Clyde, Me.

N.C. Wyeth's reputation as America's greatest illustrator rests in large part on his grand pictures for Robert Louis Stevenson's Treasure Island, the first of many classic adventure books he illustrated. "Blind Pew" (1911) for that book is often cited as the finest of all American illustrations, and "Captain Bill Bones," also in the show, is not far behind. "Black Spot" is another masterpiece from the book featured in the exhibition. It is easy to understand how N.C. Wyeth set standards by which all illustrators are measured to this day.

Under his father's tutelage, Andrew Wyeth (born 1917) blossomed into the most famous and arguably best-loved American artist of the Twentieth Century. Alternating among free-flowing watercolors -- many on view this summer in the Whitney Museum Wyeth landscape exhibition -- dry-brush work and precise temperas, his muted, probing depictions of man and land in Pennsylvania and Maine, where he maintains homes, have touched something deep in the American psyche.

"Christina's World" (1948), his portrayal of a crippled Maine woman looking from a field toward her hillside home, is perhaps the best-known painting by an American in this century. It was in the Andrew Wyeth show at the Whitney Museum of American Art this summer, and not on view at the Farnsworth, but the museum does maintain the highly evocative Olson House, backdrop for "Christina's World," in nearby Cushing, to which reverential Wyeth fans flock every year.

Andrew Wyeth's jolly but somehow foreboding "Jack Be Nimble" (1976), enigmatic "Adrift" (1982) and the wind-swept young woman in "Witches' Broom" (1990) carry on the Pyle tradition of strangeness and wonder.

Those characteristics are also prevalent in the work of Andrew's precocious son, Jamie (born 1946), who was a successful professional artist by his early twenties and continues to evolve as a painter in interesting and individualistic ways. His mocking self-portrait "Pumpkinhead" (1972) reflects both his sense of humor and the Wyeth clan's love of dressing up on Halloween. "Orca" (1990) demonstrates his affection for those who live on Maine islands, and "Guiliana and the Sunflowers" (1997) challenges viewers to figure out why the woman and child are walking through rows of dying sunflowers. The youngest Wyeth's style more closely resembles that of his grandfather than his father.

A close examination of works in "Wondrous Strange" suggests that although all four painters utilize closely observed detail and can be classified as realists, it is their creative vision evoking things whimsical, romantic and dreamlike that gives their work distinctive appeal. Their art is not always what it seems.

Pyle's penchant for placing the viewer in the middle of the action, such as in "The Fight on Lexington Common" (1898) or "The Flying Dutchman" (1902) is echoed in the work of each Wyeth. N.C.'s "Blind Pew," with the old man tapping his way toward us, or the survivor clinging to a spar in "The Wreck of the Covenant" (1913), draw us into the unfolding drama.

In Andrew Wyeth's "Trodden Weed" (1951), the viewer's vantage point in the path of the advancing boots (originally Pyle's, incidentally) prompt questions about the meaning of the imagery. In a similar vein, Jamie Wyeth practically puts us amid the birds in "The Rookery" and "Scotia Prince" (both 1977). In his masterful "Sea Star" (1986), the gull blends in with his seashore surroundings, a sense enhanced by the handsome frame of tiny seashells.

Pyle's masterful manipulation of light and shadow, particularly in nocturnal scenes like "An Attack on a Galleon" (1905) and "Vitia and the Governor" (1911) are echoed in N.C.'s "Old Pew" and "The Island Funeral" (1939), an exceptionally beautiful and moving canvas that normally hangs in the Hotel du Pont in Wilmington.

Carrying things a step further, Andrew's "Christmas Morning" (1944) has an almost surreal look, whereas his head-on moon portrait, "Moon Madness" (1982) is both beautiful and unsettling. The eerie glow from the skies adds mystery to the strange, bird-like figure in the War of 1812 tunic of Jamie Wyeth's memorable "Meteor Shower" (1993). The jacket was given by Pyle to N.C., who passed it on to Andrew, who conveyed it to Jamie, a tangible, unbroken link among all four artists.

Another element, artificial light, whether emanating from candles, a head lamp or other sources, turns up in Pyle's "Roger Bacon: (1911), N.C.'s "The Black Spot" (1911), Andrew's "Jack Be Nimble" (1976) and Jamie's "Mushroom Picker" (1963).

Pyle and N.C. Wyeth, as illustrators, had to emphasize clarity and directness in their images, whereas Andrew and Jamie have been freer to convey hidden, often ambiguous, meanings. Offering mystery rather than certainty in their art, father and son suggest the power of the unseen, as in Andrew's "Spring" (1977) and "Adrift" (1982) and Jamie's "The Lighthouse" and "The Wanderer" (both 1993).

The Wyeths, particularly Andrew and Jamie, are routinely dismissed by New York art critics as inept and outdated painters lacking depth and substance and out-of-step with the current art world. This richly rewarding exhibition should encourage objective viewers to take another look, surely a deeper look, at their work.

Those willing to spend some time will discover artwork that is skillfully created, evocative and challenging in content and rife with deeper meanings than appear on the surface. In the days ahead, scholars and serious laymen will be able to study the Wyeths in depth at the Wyeth Center, opening up all kinds of possibilities for a fairer, more positive evaluation of their achievements and place in American art history.

As "Wondrous Strange" documents, Howard Pyle's genius as artist/teacher has encouraged the Wyeths to perpetuate, in Farnsworth chief curator Larsen's words, "an American legacy from a previous century, an awareness of transcendental moments in the midst of everyday life." That legacy, along with its strong and growing permanent collection of works by other artists, suggests that the Farnsworth will increasingly be a "must-see" museum for lovers of American art.

The Farnsworth Art Museum, at 352 Main Street (on Route 1 in the heart of the Main Street Historic District) in Rockland, Me., is open year round. Telephone 207/596-6457.