Tesla was best known for his inventions which formed the basis for alternating current power, which is the kind of electric current that powers homes today. He also invented wireless radio and was known for countless other inventions. After making numerous improvements at the Edison company, he was denied a promised bonus and raise, at which point he left to focus on his own work. Date: Unknown but prior to 1896. Artist/Photographer: Photographed by Napoleon Sarony and engraved by T. Johnson.