At Home - Bill Bryson [69]
The first one was installed at the South Foreland Lighthouse, just outside Dover, and powered up on December 8, 1858.* It ran for thirteen years, and others were installed elsewhere, but arc lighting was never a huge success because it was complicated and expensive. It required an electromagnetic motor and a steam engine together weighing two tons, and needed constant attention to run smoothly.
The one thing to be said for arc lamps was that they were amazingly bright. St. Enoch’s Railway Station in Glasgow was lit with six Crompton lamps—named for R. E. Crompton, their manufacturer—that each boasted 6,000 candlepower. In Paris, a Russian-born inventor named Paul Jablochkoff developed a form of arc lights that came to be known as Jablochkoff candles. Used to light many Parisian streets and monuments in the 1870s, they became a sensation. Unfortunately, the system was expensive and didn’t work very well. The lights operated in sequence: if one failed, they all failed, like Christmas lights. Failing was something they did a lot. After just five years, the Jablochkoff Company fell into bankruptcy.
Arc lights were way too bright for domestic use. What was needed was a practical domestic filament that would burn with a steady light for long periods. The principle of incandescent lighting had been understood, and in fact conquered, for a surprisingly long time. As early as 1840, seven years before Thomas Edison was even born, Sir William Grove, a lawyer and judge who was also a brilliant amateur scientist with a particular interest in electricity, demonstrated an incandescent lamp that worked for several hours, but nobody wanted a lightbulb that cost a lot to make and only worked for a few hours, so Grove didn’t pursue its development. In Newcastle, a young pharmacist and keen inventor named Joseph Swan saw a demonstration of Grove’s light and made some successful experiments of his own, but the technology was lacking to get a really good vacuum in a bulb. Without that vacuum, any filament would burn out quickly, making a bulb a costly, short-lived indulgence. Besides, Swan was interested in other matters, in particular photography. He invented silver bromide photographic paper, which allowed the first high-quality photographic prints to be made; perfected the collodion process; and also made several refinements to photographic chemicals. Meanwhile, his pharmaceutical business, which involved manufacturing as well as retailing, was booming. In 1867, his business partner and brother-in-law John Mawson died in a freak accident while disposing of nitroglycerine on a moor outside the city. It was, in short, a complicated and distracted time for Swan, and his interests moved away from illumination for thirty years.
Then in the early 1870s, Hermann Sprengel, a German chemist working in London, invented a device that came to be called the Sprengel mercury pump. This was the crucial invention that actually made household illumination possible. Unfortunately, only one person in history thought Hermann Sprengel deserved to be better known: Hermann Sprengel. Sprengel’s pump could reduce the amount of air in a glass chamber to one-millionth of its normal volume, which would enable a filament to glow for hundreds of hours. All that was necessary now was to find a suitable material for the filament.
The most determined and well-promoted search was undertaken by Thomas Edison, America’s premier inventor. By 1877, when he started his quest to make a commercially successful light, Edison was already well on his way