A little about it
His experiments involved the fabrication and testing of many different metal filaments, including platinum.Edison then resorted to a carbon-based, high-resistance, filament. One year later in October 1879 Edison successfully tested a filament that burned for 13.5 hours.
This is a picture of the first light bulb.
This is him studying and testing his work.
This is him writing down all the tings that he tried.
Thomas Edison's Light Bulb