De Dion-Bouton Model ADL

The French had the first viable motor industry, and De Dion, Bouton et Trépardoux were among the first practitioners to take part. Bouton and Trépardoux were brothers-in-law and both engineers; Comte Jules Felix Philip Albert de Dion de Malfiance (1856-1946) was of noble birth and, according to the late historian Griffith Borgeson, “clever, amusing, the life of any party and universally popular in high society.” He was also possessed of substantial means and obsessed with steam engines.

It was the latter that led him to Charles Trépardoux, who made miniature engines. The Count and M. Trépardoux formed a partnership to build a small, personal-sized self-propelled vehicle. A four-wheeled carriage with rear-wheel steering was completed by 1883 and another, quite different model the following year. Automobile production continued at a modest pace, each one of a different configuration. In 1893, finally, a series run of steam tractors was built. One of them, coupled to a horse-drawn Victoria, competed in the 1894 Paris-Rouen trial, putting in the best performance only to be disqualified for requiring two men to operate it.

By the early 1890s, de Dion was losing his enthusiasm for steam and built two advanced petrol engines. He was able to convince George Bouton of the advantages of internal combustion, but Trépardoux remained a lifelong disciple of steam. He resigned from the partnership in 1894. De Dion and Bouton then perfected a light, single-cylinder petrol powerplant, air-cooled and with electric ignition. Applied to a tube-frame tricycle, it became a popular runabout, and these were made in several sizes and in considerable quantities until 1902.

The first petrol-engine four-wheeler was completed in 1898. Basically a tricycle with two front wheels connected by a seat, it set the stage for the 1900 vis à vis, which was water-cooled. For 1903, the engine was relocated under a coal-scuttle bonnet in the front, a style that remained in production until 1912 with some 20,000 built. Also in 1903 came the first twin-cylinder car, the Type S. All vehicles since the 1893 steam tractors had the characteristic De Dion rear suspension, a novel invention that used a dead axle to carry the weight, while drive was taken to the wheels by floating half-shafts with universal joints. The dead axle, which came to be known as the “De Dion tube,” maintained the alignment of the wheels while reducing unsprung weight. Although periodically falling from favour, the De Dion design (actually the work of Trépardoux) has enjoyed periodic revivals over the last century, notably on the P6 Rover.

A four-cylinder car was seen in the summer of 1904, when the motoring press regularly reported on the long and gruelling European tours undertaken by the prototypes. Besides the engine, the Model AD featured a number of new departures for De Dion-Bouton. The chassis was of pressed steel, and the single-plate clutch was within the flywheel, rather than appearing as individual expanding clutches for each ratio in the gearbox, and a side-lever gear-change was used. Platform rear suspension was an inheritance from the smaller models, as were automatic inlet valves, but the car was up-to-date in appearance, and its five-main-bearing crankshaft was uncommonly modern for its day.

This car was auctioned off by RM Auctions in October of 2010 at the Battersea Evolution, London.

2,544 cc, inline four-cylinder engine with automatic inlet valves, rear-mounted four-speed gearbox and final-drive unit to De Dion back axle, solid front axle with semi-elliptic springs, platform leaf spring rear suspension. Wheelbase: 119.3"

Source: RM Auctions
Photo Credit: Copyright Scott Williamson/Photodesign Studios ©

De Dion-Bouton Model ADL