This cast was part of the Phrenological Museum of Fowler & Wells, which opened in New York City in 1842. Brothers Orson Squire Fowler (1809-1887) and Lorenzo Niles Fowler (1811-1896) and their business associate Samuel Roberts Wells (1820-1875) were noted phrenologists who read heads to understand the subject's "temperament." Their Phrenological Cabinet displaying casts, skulls, and charts became a popular fixture in the city.

With this small plaster John Rogers burst onto both the art world and the political scene in New York in the months leading up to the Civil War. He boldly depicted a slave auction in progress, illustrating the tragedy of a family about to be torn apart. The father stands defiantly, with arms crossed, and his wife stands on the other side of the podium. Rogers noted that he portrayed her with Caucasian features to suggest that she was of mixed race, alluding to the sexual abuse of female slaves by their masters. She tenderly holds her baby, while her other child, a toddler, hides fearfully behind her skirt. The auctioneer presides over a rostrum with a sign that describes the sale with chilling dispassion: "Great Sale/of/Horses, Cattle/Negroes & Other/Farm Stock/This Day at/Public Auction." Rogers made clear the evil being perpetrated by the auctioneer: his hair forms two curls that resemble the horns of a devil, and what appears to be a tail peeks out from the back of his coat. Rogers himself described the work most vividly: "I have got a magnificent Negro on the stand. He fairly makes a chill run over me when I look at him. . . . The auctioneer I have rather idealized . . . two little quirks of hair give the impression of horns. The woman will be more clearly white and she and the children will come in gracefully. I am entirely satisfied to stake my reputation on it." Rogers modeled the sculpture while he was working as a draftsman for the city surveyor in Chicago. He had high hopes for the work, expecting it would be "the most powerful group I have ever made." The acclaim it earned in the Midwest inspired him to move to New York to establish himself as a professional artist. Rogers first offered it for sale at a pivotal moment, just two weeks after John Brown was executed for attempting to capture the federal arsenal at Harper's Ferry in a plan to liberate slaves. Rogers tried soliciting subscriptions for his sculpture, but apparently with little success. He wrote home in dismay, "I find the times have quite headed me off, for the Slave Auction tells such a strong story that none of the stores will receive it to sell for fear of offending their Southern customers." Rogers had misjudged his audience; he was familiar with the fervent abolitionism of his New England home, and he had not counted on New York's strong commercial ties to the South, which divided the city's sympathies. Undaunted, he hired a black man to sell the group in the streets, a common means of marketing small sculpture usually practiced by Italian artisans. He attracted the attention of the abolitionist Lewis Tappan, who brought Rogers sales in antislavery circles. The abolitionist George B. Cheever wrote a flattering notice in the Independent. The plaster was acclaimed by other abolitionist publications like the National Anti-Slavery Standard and the New York Daily Tribune. Meanwhile, Rogers developed a companion piece called The Farmer's Home (no versions are extant). Intended as a stark contrast to The Slave Auction, the group was described as follows: "The hearty, happy father, after his day's work, or on his return from the field, is seated beside his wife, with a laughing baby astride his foot [which he holds] by both hands to be tossed up and down to a tune which the father is whistling. Another frolicking fat urchin is climbing on his shoulder." A dog and kitten complete the contented image. The representation of the Northern family highlighted the injustices visited on the slave family. Rogers tried to promote the two sculptures as a pendant pair, taking them to a partner at the New York jeweler Ball and Black. The gentleman "praised them both up to the skies" but admitted that he preferred The Farmer's Home for its "more pleasing subject." In later years The Slave Auction became an icon of Rogers' patriotism, but it was never a popular work of art. It remained in his sales catalogue until 1866, but the great rarity of surviving examples suggests that few were sold. The group has enjoyed much better fortunes in its afterlife as an image and an idea in public memory and popular culture. Ironically, the image of The Slave Auction was distributed far more widely than the work itself in the form of album photographs, stereo views, and cartes-de-visite. During Rogers' lifetime The Slave Auction was said to launch his career, and he was praised for his moral courage. By 1893 the group was legendary, as one account recalled that it "infuriated" Southerners. It was often called "Uncle Tom's Cabin in plaster," a reference to Harriet Beecher Stowe's literary indictment of slavery.

Erdmann graduated from the New York University-Bellevue Hospital Medical College in 1887 and thereafter specialized in surgery and taught on the faculty of the N.Y.U. Medical School. His death mask was a gift to the Society from his daughter.

Rogers sometimes created sculptures that formed natural pairs or series, such as his three Rip Van Winkle groups of 1871 and the large-scale lawn sculptures Hide and Seek and Hide and Seek: Whoop! which he introduced a few years later. However, The Photographer and The Sitter are the only related sculptures that were sold as a pair and were compositionally dependent on one another to complete their shared narrative. The pair depicts a young woman (modeled after Roger's wife, Hattie) having her son's photograph taken. The toddler (modeled after the artist's two-year-old son, David) sits on a small table in the arms of his fashionably dressed mother. Across from him the photographer leans over his apparatus and dangles a jumping jack to focus the boy's attention. Though the two sculptures complement and complete one another, Rogers gave each an individual character. The Sitter is elaborately decorated with an eye to the sensibilities of its female and youthful subjects; the surface is embellished with varied textures, such as the lace and tasseled trim of the woman's dress, and the pedestal of the table features small concavities surrounded by greenery and inhabited by woodland creatures. In contrast, The Photographer is sparer and more masculine. The man's costume, though dapper, lacks fine texture, and the pedestal of his apparatus is decorated with simple geometric patterns. Rogers chose an experience familiar to most Americans of the period. Having one's photograph taken was a relatively inexpensive and common practice compared to having one's portrait painted. Rogers himself had had his photograph taken several times by this point, both as a private person with members of his family and as the celebrity artist he had become. The sculptural medium points up another aspect of the photographic process in the late nineteenth century: Rogers' figures are frozen in motion, and contemporary viewers would have had vivid memories of how hard it is to sit still for a photograph, since cameras were not yet able to take snapshots and required a long exposure time. Photography studios were outfitted with braces that kept the sitters firmly (if perhaps painfully) in position, but keeping a child still represented a particular challenge. Rogers himself faced the same difficulty in having his son sit quietly when posing for this sculpture of a boy who is in turn having his photo taken; perhaps Rogers resorted to photos of his son as an aid. Though the two works are now usually exhibited in close proximity to one another, they were originally intended to be placed far apart, on the opposite ends of a mantel. In this way, Rogers expanded the space covered by his narrative, but he left it up to the owner to decide just how far apart the two sculptures would sit. Rogers created a witty play between his groups, praised for their wealth of realistic detail and their naturalness, and the objects that surrounded them in a parlor setting. In their intended positions across a mantel, the mother and photographer would gaze intently at one another, trying to judge the right moment for the picture to be taken, and the boy would look at the camera, anticipating the bird that was rigged to pop out for his amusement just as the shutter clicked. These gazes would travel down a mantel that might be filled with candlesticks, vases, or other decorative objects that would seem gigantic by comparison. By allowing his groups to communicate to one another across a room, Rogers opened the space that they inhabited to include other objects, thereby pointing out their status as works of art at a time when he was most highly praised for his sculptures' fidelity to life.

Du Nouy was born in Paris and studied at the Sorbonne, specializing in biology and physiochemistry. He was the author of "Biological Time" (1937) and "Human Destiny" (1947). He joined the Rockefeller Institute in New York in the mid-1920s, then returned to Paris to work at the Pasteur Institute, where he remained until 1937, when he became director of Ecole des Hautes Etudes at the Sorbonne. He escaped from Nazi-occupied Paris and came to the U.S. in 1942.

When Rogers created this group, the sport of polo was still new or even unknown to most Americans. It was imported from India to Britain in the mid-nineteenth century, and the first polo match in the United States took place in 1876, organized by the publisher James Gordon Bennett at Dickel's Riding Academy at Thirty-ninth Street and Fifth Avenue in New York. Rogers lived nearby on West Forty-third Street. Given his interest in horses, Rogers was probably familiar with the place, and he may well have been present at the match. Polo clubs sprang up quickly thereafter in the New York area. Rogers created this group just three years later. The sculptor had already taken horses as his subject several times before, in We Boys (1936.711, 1936.661, 1929.96), Going for the Cows (1936.650, 1939.98), and The Peddler at the Fair (1947.145, 1929.85), but he had never before depicted them in motion. Polo is an astonishing technical achievement. The artist assumed the formidable challenge of depicting two horses racing toward each other, posed in very different stances, with one rearing and the other in mid-gallop. The players are dressed in the standard garb of the period, wearing the flat fezes that were a legacy of the game's Eastern origins. Rogers' well-known mastery of equine anatomy made the horses seem more alive and intensely engaged than their riders: their muscles flex and their eyes bulge. Most remarkably, the galloping horse has all four feet off the ground and is supported by a metal rod that joins his form to that of the other horse. Rogers modeled delicate parts, such as the flag and the mallets, from metal, to minimize breakage. Rogers was acclaimed for his painstaking realism, and in Polo he was careful to depict the costumes and equipment accurately. However, he apparently did not realize that the most important element of the group was in error. His virtuoso achievement of rendering a horse in three dimensions with all four feet extended off the ground had been proven physically impossible the year before. The photographer Eadweard Muybridge took a series of photographs called The Horse in Motion showing that at the moment all four of the horse's feet leave the ground they are not extended, as they are in Rogers' sculpture, but curled inward. Muybridge's experiment took place in California, so it is possible that the news, along with the photographs, had not yet reached the artist. It is not surprising that Rogers was attracted to the sport of polo, but it was a pastime of the well-to-do, and his middle-class audience did not share his interest. Polo has been called Rogers' greatest technical achievement, but it was also one of his greatest commercial failures. It disappeared from his catalogue just nine years later and is now one of his rarest groups.

This cast was part of the Phrenological Museum of Fowler & Wells, which opened in New York City in 1842. Brothers Orson Squire Fowler (1809-1887) and Lorenzo Niles Fowler (1811-1896) and their business associate Samuel Roberts Wells (1820-1875) were noted phrenologists who read heads to understand the subject's "temperament." Their Phrenological Cabinet displaying casts, skulls, and charts became a popular fixture in the city.