Wilmerding also presented the gallery with its first marsh painting by Martin Johnson Heade, “Sunlight and Shadow: The Newbury Marshes,” circa 1871-75.

One of the most compelling paintings on view is a full-scale oil study for Thomas Eakins’s last full-length portrait created in 1906. It is of Dr William Thomson, a distinguished eye doctor who treated the artist during his last years when he was losing his sight.

In one of the most significant donations of American art in recent memory, art historian John Wilmerding has presented the National Gallery of Art with 51 works by 26 American artists from his personal collection. With painters ranging from Bingham to Church and Homer to Eakins, the Wilmerding trove fills important gaps in the National Gallery’s American collection and adds depth in other areas.

The works are showcased in an exhilarating exhibition, “American Masters from Bingham to Eakins: The John Wilmerding Collection,” on view at the National Gallery through January 30. It is curated by Franklin Kelly, the gallery’s senior curator of American and British paintings, who also wrote major portions of the accompanying catalog.

Calling Wilmerding “one of the most respected and widely known authorities on American art,” National Gallery director Earl A. Powell III said the donation is “cause for celebration.”

After undergraduate and graduate study at Harvard, Wilmerding taught art (1977-83) and was deputy director of the National Gallery from 1983 to 1988. He is now the Christopher Binyon Sarofim professor of American art at Princeton and visiting curator at the Metropolitan Museum. Wilmerding’s teaching, writing and organization of exhibitions have had a significant impact on development of study and appreciation for the art of this country.

His most recent book, Signs of the Artists: Signatures and Self-Expression in American Paintings (Yale University Press, 2003), examines American painters who not only signed their works on a corner of the canvas, but intentionally placed their signature within the pictorial space of the painting. “These inscriptions,” writes Wilmerding, “are often fragments of autobiography, concentrated glimpses of self-portraiture, or, more properly, self-representation.”

When the National Gallery opened in 1941 it had fewer than a dozen American paintings. Wilmerding played a significant role in the growth of the collection to more than 1,000 works today.

At the gallery, Wilmerding curated the landmark exhibition, “American Light: The Luminist Movement,” which featured such artists as Frederic Church, Sanford Gifford, Martin Johnson Heade, John F. Kensett and, most notably, Fitz Hugh Lane. “Information Inside: The Still-Life Paintings of John F. Peto” introduced this extraordinary trompe l’oeil artist to a wide audience and distinguished his work from that of his contemporary, William M. Harnett.

While acquiring works for his own collection, Wilmerding had in mind that it might one day both fill gaps and build on strengths in the National Gallery’s existing holdings, which it emphatically does.

For example, George Caleb Bingham’s “Mississippi Boatman,” 1850, showing a tough-looking riverman guarding cargo on a moored flatboat, is the first work by this important painter to enter the gallery’s collection. Bingham “is the one artist the gallery needs in American art,” observed Wilmerding.

“Sparrow Hall,” circa 1881-82, is the gallery’s first Winslow Homer oil from his vital period in Cullercoats on England’s North Sea. This view of hardy fisherwomen and children gathered on the steps of a Seventeenth Century cottage presaged the profound themes of Homer’s subsequent career.

Wilmerding also presented the gallery with its first marsh painting by Heade, “Sunlight and Shadow: The Newbury Marshes,” circa 1871-75, as well as four exquisite floral still lifes from the 1860s.

The first painting Wilmerding acquired, while attending Harvard, Lane’s characteristically meditative “Stage Rocks and Western Shore of Gloucester Outer Harbor,” 1857, depicts sailing ships anchored in calm water in a rocky harbor. In pristine condition, it is, says Wilmerding, “one of the most beautiful pictures I know.” Adds Kelly, in a catalog entry, the painting “may fairly be ranked as one of Lane’s greatest performances.”

Wilmerding, whose scholarship brought Lane to the front ranks of Nineteenth Century American painters in the eyes of art historians, presented another of his celebrated works, “Brace’s Rock, Eastern Point, Gloucester,” circa 1864, a splendid Luminist canvas showing a marooned vessel on a lonely stretch of rocky coast. “The feeling of emptiness and quiet, the lengthening shadows of afternoon, and the presence of the abandoned boats…give these works a poignancy unsurpassed in… [Lane’s] oeuvre,” writes Kelly.

Kensett’s “An Ilex Tree on Lake Albano, Italy,” 1846, is a plein air oil sketch that pays homage to the cool, shaded beauty of the lake’s shoreline. Created during an extended stay in Europe, 1840-1847, it is the first European landscape by this Hudson River School painter to enter the National Gallery’s collection.

On view in the current exhibition are what will be the gallery’s first oils of a North American subject by Hudson River School titan Church, “Fog Off Mount Desert,” 1850, and “Newport Mountain, Mount Desert,” 1851. They are at once forceful and appealing. Church’s small pencil sketch of his mentor Thomas Cole, circa 1845, is a gem.

Since Wilmerding is a longtime summer resident of Maine’s Mount Desert, a number of artists of that picturesque region, in addition to Church, are in his collection. Included are Jervis McEntee’s view of the summit of Cadillac Mountain, “Mount Desert Island, Maine,” 1864; a pencil sketch by Alvan Fisher; four focused studies of rock formations, 1850s, and two delicate watercolors of Northeast Harbor, 1890s, by William Stanley Haseltine, and two John Marin watercolors of Somes Sound.

Others represented by depictions of Mount Desert: Alfred T. Bricher, F.O.C. Darley, William Trost Richards and Aaron Draper Shattuck. These are rich and rewarding additions to the gallery’s holdings.

Another first for the gallery is a watercolor by Thomas Eakins, “Drifting,” 1875, an evocative view of racing sailboats. One of the most compelling paintings on view is a full-scale oil study for Eakins’s last full-length portrait created in 1906. It is of Dr William Thomson, a distinguished eye doctor who treated the artist during his last years when he was losing his sight. In the 68- by 481/4-inch likeness, described by Wilmerding as “a sympathetic portrait of the greatest humanity and beauty,” the bearded doctor is seated and holding an ophthalmoscope while looking directly at the viewer. It is, says National Gallery curator Nancy K. Anderson, “a truly great painting.”

Equally intriguing is an Eakins oil study, “The Chaperone,” circa 1908, depicting a dignified black woman wearing a bandanna and knitting in a chair. This figure appears in the artist’s later versions of Philadelphia sculptor William Rush carving an allegorical rendering of the Schuylkill River.

Another sympathetic image of an African American is Eastman Johnson’s “Seated Man,” 1863, a small, deft pencil sketch that, in Anderson’s words, is a “skillfully drawn and expertly shaded” likeness of a freedman wearing a livery costume. Maine-born Johnson often conveyed his empathy for black Americans in his art.

Of particular interest is a classic trompe l’oeil work by Peto, whom Wilmerding restored to the artistic map. “Take Your Choice,” 1885, shows a haphazard jumble of well-worn books. “Peto’s books,” Wilmerding has written, “stand as embodiments of culture as diverse as the shapes and colors of the volumes themselves. For him, books were more than inert things lying around tables or shelves; they were unexpected but accessible incarnations of art.”

There is also a fine view of a scene near Northampton, Mass., “Mount Tom,” 1865, by British-born Pre-Raphaelite painter Thomas Charles Farrer, who is little known today. In it, a lone fisherman has dropped his line at the edge of water so smooth that the mirrored image of the mountain appears undisturbed.

All in all, this impressive exhibition contains enough fine art to stock a credible small museum. In donating his magnificent collection to the National Gallery, Wilmerding has made a notable and noble gift to the nation. It is a gesture that enhances the distinguished legacy of this respected scholar, teacher and now, philanthropist. American art aficionados can rejoice that after the show of the Wilmerding collection closes in January, the works enter the gallery’s permanent collection.

Fortuitously coinciding with the Wilmerding exhibition and gift is a new book, National Gallery of Art: Master Paintings from the Collection, that places these new additions to the collection in the context of the museum’s imposing holdings. Modeled on then-director John Walker’s classic National Gallery of Art, Washington, 1984, this sumptuous new volume features a fresh selection of works, including an impressive number acquired in the past 20 years.

The graceful commentaries of John Oliver Hand, curator of Northern Renaissance Paintings, offer interesting and enlightening insights into masterworks ranging from Giotto, Sandro Botticelli and Leonardo da Vinci to Jackson Pollock, Roy Lichtenstein and Jasper Johns.

The handsome volume documents that although the National Gallery is relatively young – it opened in 1941 – it boasts one of the great collections of art in the world. As director Powell notes in the foreword, the museum’s “collection bears a patina that belies its youthful formation…[I]t has become one of the world’s great repositories of European and American masterpieces.”

The coffee-table-size, 474-page book, with 445 illustrations, is published by the National Gallery in association with Harry N. Abrams, Inc. It is priced at $60 (hardcover).

The National Gallery of Art is on the National Mall between 3rd and 9th Streets at Constitution Avenue NW. For information, 202-737-4215 or www.nga.gov.