Originally introduced as the 40/50 hp, the Rolls-Royce Silver Ghost is the foundational model that established the brand's enduring reputation for building the finest motor cars in the world. Built upon a rigid ladder-frame steel chassis with solid axles and semi-elliptic leaf spring suspension, the vehicle was supplied as a rolling chassis, allowing prestigious coachbuilders including Barker, Hooper, H.J. Mulliner, and Brewster to construct bespoke bodies spanning tourers, limousines, coupés, sedans, roadsters, and convertibles. The powertrain initially consisted of a 7.0-litre side-valve inline six-cylinder petrol engine producing approximately 48 horsepower, featuring a pressurized lubrication system and a seven-bearing crankshaft for extreme smoothness. In 1909, the engine displacement was enlarged to 7.4 litres, raising output to between 60 and 80 horsepower. Transmission options evolved across production from a four-speed manual with overdrive to a three-speed gearbox and back to an advanced four-speed unit. The car achieved legendary status through non-stop long-distance reliability trials showcasing unprecedented silence and mechanical resilience. Major upgrades included standard electric lighting and starting systems in 1919, followed by the introduction of mechanical servo-assisted four-wheel brakes in 1923. Production took place in Derby, England, and Springfield, Massachusetts, until being succeeded by the New Phantom in 1925.