Imagine the heated discussions that took place among the Weir family of artists as they walked along the hills and stone walls at Weir Farm around the turn of the century. The Impressionist movement was looming on the horizon, a revolutionary new approach to art, and J. Alden Weir, owner of the farm at Nod Hill Road, was repelled at first.

After viewing an exhibit of French Impressionists in Paris in 1877, J. Alden Weir wrote to his family, "I never in my life saw more horrible things ... They do not observe drawing nor form but give you an impression of what they call nature. It was worse than the Chamber of Horrors."

J. Alden Weir would later become one of the first and most influential American impressionists.

His evolution, and the work of his father, Robert, and his brother, John Ferguson Weir, are the subjects of the first major exhibition of their work, "The Weir Family: 1820-1920: Expanding the Traditions of American Art," on view at the New Britain Museum of American Art until Sept. 30. The exhibition displays 74 paintings by the Weirs and is curated by Marian Wardle, curator of American art at Brigham Young University Museum of Art.

"We at Weir Farm Art Center are thrilled to have this concentrated focus on the Weir family and their many artistic accomplishments," said Janice Hess, executive director of Weir Farm Art Center.

The 60-acre farm in Wilton where the Weirs lived and painted is Connecticut's only national park, and the only national historic site dedicated to an American painter.

Linda Cook, superintendent of Weir Farm, said J. Alden Weir's first artistic allegiance was to "the precision drawing of the Academic style, as well as the romantic plein-air work of the Hudson River School as practiced by American artists such as Thomas Moran and Albert Bierstadt."

The landscapes of Weir Farm helped inspire the dramatic shift in his style, according to the farm's website.

"His artistic views changed over time, particularly as he developed an intense relationship with the 153 acres of land in Branchville that he purchased in 1882," according to the website. "As he designed his own property to create a pleasing variety of attractive views, he increasingly drew upon Impressionist-style techniques to capture these scenes on canvas."

Like the famous French Impressionist Claude Monet, "Weir endeavored to surround himself with the color and beauty that he desired to celebrate in his paintings."

"The park is known for its varied landscape, the combination of color, stone, bedrock, trees, orchards, fields and pond," Ms. Cook said. "J. Alden Weir loved to paint in the changing dappled light created by the canopy of sugar maples. As he perfected his Impressionist style, he used brighter colors and quick brush strokes to capture the rural scenes."

Ms. Cook described the exhibit at the New Britain Museum of American Art as "stunning. As a body of work, the art draws the visitor in to the amazing skill and talent that the Weirs had at their command. This family legacy of art is a defining moment for Connecticut, as a defining contribution to the national arts arena. For J. Alden Weir, it extols his abilities as a master of the Impressionist Art movement."

Ms. Cook said many of the paintings "could have once hung in the Weir House, or were painted of the property or in the Weir Studio."

For example, one of J. Alden Weir's paintings in the exhibit, Sunlight, Connecticut, captures the lush landscape at Weir Farm.

The first teacher of the two younger Weirs was their father, Robert. His most famous painting, Embarkation of the Pilgrims, hangs in the Capitol Rotunda in Washington, D.C., and a reproduction of this work is included in the exhibit at the New Britain Museum of American Art.

By the time J. Alden Weir embraced impressionism, his father had died in 1889, but J. Alden Weir influenced his brother, John Ferguson Weir, as seen in their later floral studies.

John Ferguson Weir was a painter of landscapes and industrial scenes, and he established America's first academic art program, at Yale University.

The major change in the artistic style of J. Alden Weir may be seen in his two self-portraits, one as a young man and one as an older man.

According to the study by Ms. Wardle, J. Alden Weir's evolution also took root as he grew to appreciate the Impressionist paintings exhibited in New York in 1886. He was also inspired by early Impressionist advocates Theodore Robinson and John H. Twachtman, who painted at Weir Farm and called it "The Land of Nod." J. Alden Weir gradually adopted the feathery brushwork and outdoor subjects of the Impressionists.

"Through Sept. 30, visitors and residents of Connecticut have a rare experience to view these paintings, in conjunction with Weir Farm National Historic Site, to better enjoy and be a part of the arts that so define our history and culture," Ms. Cook said.

"The Weir Family: 1820-1920: Expanding the Traditions of American Art" will be on view at the New Britain Museum of American Art until Sept. 30. Information: 860-229-0257.