Roberts was a noted art collector and staunch supporter of American artists who never sold or exchanged a painting after he bought it. He was considered the prototypical
New York City patron, like
Gilpin in
Philadelphia and
Harrison Gray Otis in
Boston. He "made no pretensions to connoisseurship, but was guided in his purchases simply by fancy, or with a view to assisting some needy artist." Roberts formed his collection of 335 paintings which he bought for $10,000 (at the time, an enormous sum). Roberts built an art gallery, attached to his home, 107
Fifth Avenue (at the southeast corner of
18th Street), where he displayed his collection, which included
Rembrandt Peale's
Babes in the Wood,
Daniel Huntington's
Venice,
Good Samaritan and
Old Lawyer,
Frederic Edwin Church's
Rainy Season in the Tropics and
Coast of Maine,
Régis François Gignoux's ''Hawk's Nest, West Virginia'',
Richard Caton Woodville's
War News from Mexico,
Asher Brown Durand's
Indian Rescue, Schaeffele's ''Marie de Medici's Visit to Ruben's Studio'',
Johann Georg Meyer's
First Lesson,
Constant Troyon's
After the Hunt,
Paul Falconer Poole's
Pension Agent,
Charles Verlat's
Sheep in Pasture,
Paul Delaroche's
Napoleon at Fontainbleau,
Ernest Meissonier's
The Smoker (1849)
Thomas Sidney Cooper's
Monarch of the Plain,
Édouard Frère's
Mother and Infant and
The Industrious Mother,
John Frederick Kensett's
Noon by the Sea Shore and
Franconia Notch,
Henry Peters Gray's
Rose of Fiesole and
Just Fifteen,
George A. Baker's
Love at First Sight,
Wild Flowers and
Children of the Wood,
John George Brown's
His First Cigar,
Thomas Cole's
Old Mill,
James McDougal Hart's
Old Homestead and
Morning in the Adirondacks,
William Henry Powell's
Landing of the Pilgrims,
William Sidney Mount's
Raffling for a Goose,
Robert Swain Gifford's
On The St. Lawrence and
View of Quebec,
Eugene Benson's
Thoughts in Exile,
Thomas Sully's
Woman at the Well and
A Girl Offering Flowers at a Shrine,
Seymour Joseph Guy's
A Field Daisy and
Good Sister,
Charles Loring Elliott's
Portrait of Himself, and
George Henry Boughton's
Gypsy Women,
Jean-Léon Gérôme's
The Egyptian Conscript,
James Augustus Suydam's
On the Beach,
Charles Baugniet's
Dressing for the Ball,
Benjamin Vautier's
The Letter, as well as works by
M. H. Koekkoek Édouard Detaille. In addition to the 1876
Indian Vase by his son-in-law
Ames Van Wart, Robert's collection included 1,000 different numbers in bronze, art objects and furnishings. His sculptures included
Erastus Dow Palmer's medallion base-reliefs
Night and
Morning,
Franklin Simmons's
The Promised Land, and Voso's
Cupid and Psyche. They moved to London and the collection remained in the Fifth Avenue home, which remained unoccupied other than during the winter of 1893 to 1894 when
Cornelius and
Alice Gwynne Vanderbilt leased the mansion while they were expanded their
chateau at Fifth Avenue and
57th Street. In total, $41,754 () was received for the sale of 172 pictures, $8,764 during the first night's sale and $32,990 the following night at Chickering Hall. The new building, extant today at 105 Fifth Avenue, was the original location of the
Barnes & Noble chain of bookstores from 1932 to 2014. ==Collection==