to be shown at the 1885 International Inventions Exhibition in London. The vehicle was built by the Merryweather Fire Engine company in Greenwich, in 1888. the Butler Petrol Cycle (first recorded use of the term) It was a three-wheeled vehicle, with the rear wheel directly driven by a 5/8hp (466W) 600 cc (40 in3; 2¼×5-inch {57×127-mm}) flat twin four stroke engine (with magneto ignition replaced by coil and battery), equipped with rotary valves and a float-fed carburettor (five years before Maybach), and Ackermann steering, all of which were state of the art at the time. Starting was by compressed air. The engine was liquid-cooled, with a radiator over the rear driving wheel. Speed was controlled by means of a throttle valve lever. No braking system was fitted; the vehicle was stopped by raising and lowering the rear driving wheel using a foot-operated lever; the weight of the machine was then borne by two small castor wheels. The driver was seated between the front wheels. It wasn't, however, a commercial success, as Butler failed to find sufficient financial backing. Another early internal combustion, petroleum fueled motorcycle was the Petroleum Reitwagen. It was designed and built by the German inventors Gottlieb Daimler and Wilhelm Maybach in Bad Cannstatt, Germany in 1885. This vehicle was unlike either the safety bicycles or the boneshaker bicycles of the era in that it had zero degrees of steering axis angle and no fork offset, and thus did not use the principles of bicycle and motorcycle dynamics developed nearly 70 years earlier. Instead, it relied on two outrigger wheels to remain upright while turning. The inventors called their invention the Reitwagen ("riding car"). It was designed as an expedient testbed for their new engine, rather than a true prototype vehicle. First commercial products In the decade from the late 1880s, dozens of designs and machines emerged, particularly in Germany and in England, and soon spread to America. During this early period of motorcycle history there were many manufacturers, since bicycle makers were adapting their designs for the new internal combustion engine. In 1894 Hildebrand & Wolfmüller became the first series production motorcycle, and the first to be called a "motorcycle" (). However, only a few hundred examples of this motorcycle were ever built. The first instance of the term "motor cycle" also appears in English the same year in materials promoting machines developed by E.J. Pennington, although