Gretchen Townsend's research on the centripetal armchair produced between 1850 and 1858 by the American Chair Co. of Troy, New York demonstrates how, beneath the chair's upholstered cushion, its springs and cast-iron base enabled it to swivel, flex, and recline in any direction, innovations inspired by the manufacturer's signature production of reclining railway seats. Such developments were made with an interest in a more comfortable design. Townsend argues that while these features failed to endure in the parlour setting, they were embraced by manufacturers of ergonomic office furniture who captured the market for chairs that facilitated movement and support. The dental patient shared office workers' demands for simultaneous ergonomics and comfort. Furthermore, Jennifer Pynt and Joy Higgs also describe a divide between parlour seating and patent seating in the Victorian period, attributing it to a difference between chairs intended to better a sitter's health. According to Pynt and Higgs, such patent chairs were frequently designed by medical practitioners, and Salmon might have been taking a cue from his colleagues—doctors such as chiropractors—in his decision to enter the field.
Following dentist William Morton's successful use of anaesthesia in 1846, there was an increasing need for chairs with reclining backs. In his 1866 publication, The Principles and Practice of Dental Surgery, Chapin Aaron Harris recommends lowering a patient in preparation for the administration of anaesthetic agents, something he notes requires a dentist to own an operating chair with a moveable back. This reclining feature was essential in supporting the patient's body when he or she lost consciousness. Salmon's chair boasted a reclining back. In 1867, the year after Salmon applied for a patent, a reclining back would have been a supplemental feature, given that a dental trade catalogue's standard operating chair did not have such a capacity. But by 1876, such a feature was considered essential and the same company's catalogue from that year exclusively offered reclining designs.
Because patents targeted mechanical improvements in different parts of a chair, sometimes the most advanced and thus desirable chair was not always distinguishable from the rest. The chair with the most innovative headrest may not have had an equally well-designed underbody mechanism. Distributors compensated for this unevenness by selling chairs in an almost piecemeal fashion, as when the S.S. White Dental Manufacturing Company offered Perkins' Dental Chair with 'Whitcomb's Head-rest substituted' for thirty extra dollars in 1867. For this reason, while Salmon announced his central innovation was in his chair's underbody, his patent text claims its other improvements as well. In this description, Salmon differentiates his headrest from a previously patented one that permitted only a few positions. Instead, his chair used a perfected joint that allowed the headrest to be positioned at any angle within its range of movement. In Salmon's era, advances in dental surgery made patent designs for headrests on dentists' chairs increasingly important. An 1859 treatise by Sir John Tornes on dental surgery notes that while easy chairs had previously been tolerated, improvements to professional chairs permitted operative dentists to position their patients' heads in lines both conducive to the operation and that offered better support.
While Salmon perfected D. W. Perkins's chair's underbody mechanism, he preserved its other features including its plush seat and mahogany wooden armrests, carved with swan-head terminals. These design features recall late Neo-Classical sitting room furniture such as John Finlay's 1832 sofa for Hampton's Drawing Room. This degree of grandeur might have represented Salmon's attempt to cater to a more elite clientele. But most importantly, in keeping with Salmon's interest in establishing a patient's comfort with the underbody, the upper part of the chair also would have guaranteed a patient's ease. Here, the chair's aesthetic design retained associations with the domestic sphere and would have made the dental office a less intimidating, and even familiar environment. Trade manuals such as The Dental Office and Laboratory encouraged dentists to take their patients' comfort into account, advising on the duration for which patients could easily be kept in the chair and even suggesting remedies to mask procedural smells such as placing pastilles with the pleasant odors of myrrh and nutmeg at the base of operating chairs. While the chair's metal base incorporated modern engineering, its upper section was likely intentionally anachronistic and traditional. And because patent designers were focusing their exacting modifications on the underbody mechanisms and preserving the style of the top of the chair, swan-carved armrests continued to appear in patented dentists' chairs through 1874, as in a design by George W. Archer, intended for both dentists' and barbers' shops. Like dentists, barbers in 1874 were using sharp devices such as razors and scissors, making the comfort of their clients as important as that of the dentist's patients.
While such Neo-Classical furniture features were emblematic of tradition, their materials also meant they were associated with luxury. Throughout the nineteenth century, advertisements emphasized chairs' costly materials, such as the turn-of-the-century Harvard Chair, upholstered in seal skin, which was marketed as 'one of the most ... beautiful ... dental chairs made.' Likewise, other dental objects were designed to express extravagance and status. Utilitarian objects such as gasometers, used to store and administer the sedative agent nitrous oxide during dental procedures, were sold with either nickeled or japanned ornamental bases [4]. In their design, stands for the engine bits of dentists' drills recalled cake dishes and jelly moulds with a series of concentrically layered trays, all capped by a round finial. Surviving photographs from the late nineteenth century, such as one showing the Boise City office of Dr. Pyle, capture how the decorative impulse of the Victorian era influenced dentist office design, resulting in draped, fringed curtains, flowers, and a fanciful elephant statue.
These nineteenth-century dentists' investments in ornament conformed with a long tradition of lavish dental devices: itinerant dentists kept ivory-handled tools in shagreen cases, and the first practical dental instrument case, manufactured in New York City in 1840 by John D. Chevalier, was made in the buyer's choice of rosewood, walnut, mahogany, or leather, embellished with heavy brass or German silver mountings and silk velvet lining, and held mother-of-pearl-handled, bejewelled instruments. The valuable materials used in dentists' instruments would have been especially meaningful to patients at a time when commissions for gold fillings and ivory and porcelain teeth demanded that dentists have access to quality suppliers. An 1867 dental trade catalogue demonstrates the significant price differential between the cheapest standard model of dentists' chairs, unadorned beyond a stain used to imitate elegant woods, for $85, and the most costly design by J. O. Whicomb which featured an upholstered tilt seat and footrest and carved rosewood feet and arms. Likewise, the velvet and carved walnut in Salmon's chair made claims of professionalism by suggesting its owner's commercial success; a dentist using a Salmon chair was one who could afford to elegantly outfit his dental office.
Historically, dentists made their claims of authority in public spaces through spectacle, as dentists at fairs often worked on an elevated stage. In some instances, these stages included wings and were explicitly intended for entertainment purposes; jugglers, clowns, and conjurers drew attention prior to dental surgeries. Engravings from France and Britain in the eighteenth and nineteenth centuries show how this carnivalesque practice endured [5]. Itinerant dentists were also a trope in depictions of nineteenth-century rural life, and scenes emphasized locals' fascination following this novel visitor's arrival. Even when dentists' offices evolved, space constraints originally precluded separate waiting and operating rooms, and a gallery of spectators, each awaiting their own treatment, was frequently depicted in both caricatured and realistic scenes of dentists' offices. In these public settings, a dentist became as much a showman as a trade practitioner and his chair as much a stage as a professional tool. Ultimately, spectators served as sureties, giving patients confidence that their dentists were being watched and held accountable in performing honest work.
When the dental office became a private setting in the mid-1800s, the dentist's audience disappeared and the onus fell upon the patient to mind the dentist's work. The lavish decoration seen in Victorian-era dentists' offices may be a palimpsest of the industry's performative tradition, endowing patients with the power of spectators and encouraging them to be the ultimate appraisers of their dentists' work. Footstools sold in an 1867 dental trade catalogue emphasized the chair's height, making it reminiscent of a stage in a medieval market. The dentist used levers and pulls to set the chair in motion, becoming a stage master. An 1867 dental trade catalogue listed pearl handled mirrors among its standard products which were essential devices in allowing patients to watch their dentists work. These features glorified spectatorship, making a dentist's operation a practice of wonder rather than fear. Ultimately, a dentist was responsible for realizing a transformation for his watchful patient.
Like in medieval times, Salmon was working in an period that continued to prize showmanship, as shown by the theatrics of popular impresarios such as P. T. Barnum, who staged hoaxes and paraded curiosities, claiming them to be miracles for his amazed audiences. Although he was established in a permanent, professional office in Boise, the dentist J. C. Leonard was reported to have travelled through the West in the late 1800s, giving lectures on his dentistry practice and exhibiting barrels of teeth that are now in the museum of the University of Michigan. Before Salmon's death, Edgar Randolph Parker was working against the trend toward sterile, standardized dentistry offices and imagining new ways to attract clientele. Parker eventually devised a dental circus in partnership with a former employee of Barnum, pulling teeth in an apparently painless fashion in the company of a brass band, contortionists, and dancing women. While such performances were often denounced as quackery, Parker had graduated from the Philadelphia Dental College like Salmon. While Parker was working in the lineage of the medieval dentist who performed at fairgrounds, his intent was not a macabre attempt to profit off pain; instead, he sought to defy his audiences' expectations with the miracle of painlessness.
In some ways, like Leonard and Parker, Salmon himself was employed to capture an audience. Much scholarly discussion of Thomas Eakins's The Gross Clinic and The Agnew Clinic—realist paintings fourteen years apart that both capture surgeons, Samuel D. Gross and David Hayes Agnew respectively, working before an audience of students—has focused on the performative nature of the medical profession. Like Gross and Agnew, Salmon was a university lecturer, and it was his responsibility to command Harvard dentistry students' attention in the lecture halls of Massachusetts General Hospital. For Salmon and his students, dental operations were affairs to be observed as well as personally undertaken. Furthermore, Salmon was an active and dynamic presence in his professional community, serving in various positions on the Massachusetts Dental Society and frequently travelling to other states' dental association meetings to perform clinics and give papers. His side-interest in fashioning innovative patent designs, including ones for entertainment objects such as the autoharp, demonstrates he was attuned to popular interests. Salmon may have had theatrical design in mind when he endowed his chair with swan armrests and velvet upholstery. These dramatic features subtly invoke the relationship of the performer and spectator for the dentist and patient, further guaranteeing a patient's comfort by associating the dental procedure with a spectacle to be anticipated and observed rather than a dreaded operation to be feared.
This essay has sought to argue that Salmon's patent model was intended to establish his professional reputation in the industry by demonstrating his keen awareness of the needs of the dentist and the patient. In the same year as he submitted his patent model, a report about the twelfth annual American Dental Convention in the November 1866 issue of the periodical, The Dental Cosmos, describes how 'Dr. Salmon exhibited a dental chair capable of being inclined backward, laterally or obliquely, at an angle of 40 to 70 degrees.'45 In addition, Salmon presented his instrument rack and demonstrated for his peers how his automatic mallet, used to condense gold when filling a cavity, was designed so that 'a greater variety of blows ... can be obtained ... with little noise.'46 The next year, The Dental Cosmos's careful coverage of professional advances included endorsements of Salmon's mallet.