For comparison, Carl Benz, who is generally recognised as the inventor of the modern automobile, built his first working motorcar in 1885, and unveiled it to the public in 1886.
The rear wheel was directly driven by a 5/8hp (466W) 600 cc (40 in3; 2¼×5-inch {57×127-mm})[2] flat twin four-stroke engine (with magneto ignition replaced by coil and battery),[2] equipped with rotary valves and a float-fed carburettor (five years before Maybach),[2] and Ackermann steering,[3] all of which were state of the art at the time.
[4] Butler improved the specifications of his vehicle over the years, but was prevented from adequately testing it due to the Locomotives Act 1865 (the Red Flag Act), which legislated a maximum speed for self-propelled road vehicles of 2 mph (3.2 km/h) in built up areas and 4 mph (6.4 km/h) in rural areas.
[citation needed] Butler wrote in the magazine The English Mechanic in 1890, "The authorities do not countenance its use on the roads, and I have abandoned in consequence any further development of it.
"[4] Due to general lack of interest, Butler broke up his machine for scrap in 1896, and sold the patent rights to Harry J. Lawson who continued manufacture of the engine for use in motorboats.