In the 18th century Sweden’s scientific revolution took off. Previously, technical progress had mainly come from professionals who had immigrated from mainland Europe. In 1739, the Royal Swedish Academy of Sciences was founded, with people such as Carolus Linnaeus and Anders Celsius as early members. From the 1870s, engineering companies were created at an unmatched rate and engineers became heroes of the age. Many of the companies founded by early pioneers are still internationally familiar. Gustaf Dalén founded AGA, and received the Nobel Prize for his sun valve. Alfred Nobel invented dynamite and instituted the Nobel Prizes. Lars Magnus Ericsson started the company bearing his name, Ericsson, still one of the largest telecom companies in the world. Jonas Wenström was an early pioneer in alternating current and is along with Serbian inventor Tesla credited as one of the inventors of the three-phase electrical system.