Who invented the automatic gear shift and the supercharge system for internal combustion engines?

Ferdinand Porsche invented the first supercharged Mercedes-Benz SS & SSK sports cars in Stuttgart, Germany in 1923. In 1832, W. H. James invented a rudimentary three-speed transmission. Panhard and Levassor are credited with the invention of the modern transmission - installed in their 1895 Panhard. On April 28, 1908, Leonard Dyer obtained one of the earliest patents for an automobile transmission. The first Automatic transmission in an American car was Oldsmobile.