Engine – 298 Cubic Inch L-Head Inline Four-Cylinder
Transmission – 4-Speed Manual Gearbox
Horsepower – Approximately 70 HP
Wheelbase – 132 inches
Production – Undocumented; limited production within the broader Series 5 model range
“The Car for the Man Demanding Speed with Safety”

The Mercer Automobile Company emerged in the early 1910s in Trenton, New Jersey, evolving from the Walter Automobile Company and the earlier Walter and Roebling-Planche cars built in the same factory. Backed by members of the Roebling and Kuser families, Mercer entered the American market at a time when the performance-oriented “sporting” automobile was still a burgeoning concept, and quickly became associated with light, purposeful machines distinguished by minimal bodywork and an emphasis on speed and agility.

The company’s most recognizable expression, the Raceabout, became a model that came to define Mercer in the public imagination. The early T-head Raceabouts (though modest in displacement and nominal horsepower) achieved notable success through the employment of minimal weight, spartan appointments, and a focus on mechanical efficiency. Contemporary accounts credit the design and engineering of these cars to Chief Engineer Finley Robertson Porter, working from the ideas of Industrialist Washington A. Roebling II, who would later perish in the sinking of the R.M.S. Titanic. By 1911 and 1912, Mercer Raceabouts were competing regularly and achieving victories and setting class records by drivers such as Ralph De Palma and Spencer Wishart.

Despite this early prominence, Mercer’s formative period was brief, and the company soon found itself in a period of ideological uncertainty. Upon Roebling II’s aforementioned death in 1912, and Porter’s later resignation from the company in late 1914, subsequent engineering leadership shifted to Eric H. Delling, who marked a shift away from T-head construction and toward L-head engines. In addition to changes in powertrain design, Mercer placed increasing attention on comfort and enclosed coachwork. By the mid-1910s, Mercer was no longer defined by the same competitive ambition that had defined the marque’s early Raceabouts, and the Mercer Automobile Company entered a period of financial instability and ideological diversion that extended into the 1920s.

By 1920, the new Mercer Series 5 reflected a far more contemporary “conventional” approach to the marque’s identity, with a single mechanical platform offered across a range of body styles ranging from roadsters to 7-passenger touring sedans—including enclosed and sometimes formal coachwork—indicating an emphasis on versatility that contrasted with the strict purpose-built ethos of Mercer’s former Raceabouts.

Supporting documents confirm that this 1921 Mercer Series 5 Raceabout is among the most thoroughly documented examples of the marque, with a clear and continuous ownership history preserved across multiple decades. The car remained in single-family ownership from 1926 through 2010 and has long been recognized as a carefully stewarded and limited-owner example. Surviving film footage and period correspondence further document the car’s sustained public presence and operability throughout the early collector era.

Equally as significant is the car’s condition and approach to preservation. Supporting documentation indicates that this Mercer has never been comprehensively restored, with any work undertaken historically limited to care and maintenance performed as needed rather than as part of a formal restoration campaign.

Surviving film footage from 1939–1940 documents this Mercer’s presence at early Vintage Motor Car Club of America gatherings, including events held in conjunction with the 1940 World’s Fair at Raceland–Framingham. The footage confirms the car’s participation in the earliest organized vintage motoring movement in the United States, placing it among a small group of automobiles recognized and preserved well before the postwar rise of “concours culture.” Its documented appearance alongside other significant prewar automobiles of the period underscores the Mercer’s early recognition within the same preservation milieu that included cars such as the 1912 Simplex 50HP Torpedo Tourer by J.M. Quinby & Co.

The restrained stewardship has allowed the car to remain an authentic, continuously used example, distinguished by preservation through attentive use–rather than reconstruction, and this Mercer stands today as a well-documented reference point for the Series 5.