CHAPTER ONE PAPER THAT A BREATH WOULD BLOW AWAY By October 1879 the electric light had been Thomas Alva Edison’s obsession for months Day after day he worked in his laboratory The subject that occupied most of his thoughts was the filament This thin wire inside the light bulb glowed to create light Getting such a delicate object to burn brightly while also lasting a long time was a tough task indeed His earlier Edison and his assistants searched for a filament material that would burn bright and last for many hours 5
experiments had used filaments of carbon Often made from paper or cardboard carbon was cheap and burned well perhaps too well These early carbon experiments burned out quickly They lasted ten to fifteen minutes at the most Between late 1878 and October 1879 Edison focused on platinum He had better results but they came at a cost Platinum was very expensive It did however burn hot and bright Edison showed off his platinum light to reporters and they were impressed One New York Sun reporter declared The strip of platinum that acted as a burner did not burn It was incandescent It threw off a light pure and white Edison boasted of the light’s virtues to anyone who would listen Unlike those fueled by gas Edison’s light did not produce any smoke or dirt It was the first clean artificial lighting It was also the first type of lighting that did not produce a flame But Edison kept one thing secret His platinum filament light would burn out after only a few hours 6
PERSPECTIVES Dealing with Doubters Edison did not invent the concept of the electric light nor had he been the first to try it There had been many failures in the field By the 1870s other inventors had begun to believe such an invention was impossible In 1879 Dr Paget Higgs wrote that the science required for a light bulb is incompatible with the well-proven law of conservation of energy Higgs’s statement fit with the popular opinion at the time Many leading scientists had given up their work on the subject The bulb’s short life span was not practical Edison’s light needed to last for several hundred hours He experimented with ways to make the filament last longer By removing air from the bulb Edison was able to get better results His research showed that air weakened the metal as it was heating That made it melt faster Removing the air from the bulb thereby creating a vacuum prevented this But even with that effect the problem remained platinum was expensive Edison sought to find a cheaper source of the metal 7
