Four wheels good, two wheels bad. That's the axiom car guys go by. Of course, it's exactly opposite for motorcycle fiends. What if cars had two wheels and balanced on their own? The Schilovski Gyrocar did it in 1914.
The gyroscopic effect is one of those scientific magics which is incredibly captivating and yet not widely understood. In modern usage gyroscopes are used extensively in professional photography equipment and scientific equipment for their ability to provide a stable orientation and resist movement caused by outside forces. Once upon a time they caught the attention of one Dr. Pyotr Shilovsky, a inventor, tinkerer and Russian national who imagined a world where gyroscopes were used extensively in transportation systems.
In 1912, Shilovsky worked with engineer Louis Brennen to develop designs for a two-wheeled, narrow-body car with a a 1,344 lb gyroscope sitting in the middle of the chassis to provide a stabilizing force. Shilovsky commissioned the Wolseley Tool and Motorcar Company to build the machine and after about a year of development work they'd completed work and had a functional, self-balancing automobile.
The car featured a 16-20 HP Wolseley engine running both the flywheel and the rear drive wheel, a pair of outrigger wheels which deployed either by lever or automatically when the flywheel dropped below a set speed, three tandem rows of seating up to six passengers with a traditional steering wheel for the driver. The steering mechanism was quite ingenious, as by nature moving anything attached to a gyro is difficult. The steering wheel was hooked to a system of shafts, ratchets and 95 lb pendulums which allowed the gyro to be manipulated in such a way as to allow steering and continue stabilizing the machine.
A reporter from The New York Times was on-hand to experience the car's official demonstration in London in May 16th of 1914, and described the ride thusly:
At 3 o'clock in the afternoon the long car, with the single steering wheel set bicycle fashion in front of the shoe-shaped bonnet that covers the 16-20 horse power engine, with a dashboard form of cooler behind it and two electrical fans to induce draght of air to the radiators, came into Portman Square at a walking pace. The inventor sat beside the driver while the car made several circuits of the square, sometimes at slower than walking pace, the curves being negotiated without difficulty at that rate, and, of course, always with the vehicle on an even keel, as distinct from inclining it in the manner in which a cyclist rides around a curve. Then the car was brought to a stand, but as the gyroscope was kept in action it stood upright, and was unaffected by men stepping on to or off it or leaning against it.
At the outbreak of the first World War later that year, Shilovsky returned to Russia and Wolseley, having not heard from him over an extended time and assuming he'd been a casualty of the conflict, and not wanting to store the car or scrap it, buried it in the ground. There is stayed until 1938 when it was dug out of what became a train switching yard and the car was restored and put on display at Wolesley's company museum. Sadly, the car was broken up for scrap in 1948, never to be seen again.
[The New York Times, "How New Gyro Car Worked In London," May 17, 1914,
DSelf, Wikipedia]