Pietro Vassena is often referred to as a genius. Best known in the motorcycle world for the flat-twins which powered Carniti and the 125cc horizontal singles (and later twins) fitted to Moto Rumi, he began to make his mark on the world in the early 1920s developing tools for mechanical workshops in his home town of Lecco, on Lake Como. He is credited with many advancements for marine engines, developed what was later known as the jet ski, and built a submarine which plunged to the bottom of Lake Como to establish a world's record. Pietro was photographed waving to John F. Kennedy whilst "walking on water" with his paddle-powered ski boots.
In 1939 he developed a system named the "Autargas Vassena". It was tested using an 85 HP Isotta Fraschini on the Lecco-Rome route, at a cost of L.150 for the petrol. The usual cost would have been L.1000.
During the war he developed a system to power internal combustion engines using wood and charcoal. It is understood that it became widely used.
In 1954 he built a motorcycle with a cast aluminium frame and cardan drive. That year he also developed a system to allow a Beretta pistol to discharge 20 rounds in a single burst, and sold a patent to MV Agusta for an ignition component.
Like many others of enormous talent, he was unburdened by societal norms, making him at times rather frustrating to work with. The Germans apparently did not much like him - in 1944 his wife was sent a list of those in the Lecco area to be eliminated. His name was high on the list.
Pietro died in 1967, his main regret being that he had not been successful in developing something which few had heard of at the time - a hydrogen engine which he began working on in 1963.
His name appears numerous times in these pages: Search Vassena
Some of the above is a bit garbled and possibly not 100% accurate, but it appears to be largely correct.
Sources: panorama.it/pietro-vassena-leonardo-del-lago-lecco, et al