FREE LIGHTING PEOPLE 1ST EDITION PDF Rossella Vanon | 9781138119888 | | | | | Blue light has a dark side - Harvard Health Lighting People 1st edition seems to be disabled in your browser. You must have JavaScript enabled in your browser to utilize the functionality of this website. The history of the light bulb is filled with rivalry, failures and great achievements. The electric light bulb has been called the most important invention since man-made fire. The light bulb helped to establish social order after sundown, extended the workday well into the night, and allowed us to navigate and travel safely in the dark. Without the light bulb, there would be no nightlife. However, creating a steady and affordable source of illumination was not as easy as many history textbooks suggest. The modern light bulb is the result of many innovators' work and Lighting People 1st edition improvements over years. The First Artificial Sources of Light. Before the arrival of electric lighting, people used a variety of tricks for navigating their neighborhoods at night. In The Downs, an area near the English Channel, patches of chalky soil were used as beacons known as down lanterns. In wooded areas, bark was strategically cut from trees to expose the lighter wood underneath. However, on most clear nights, the moon and starlight were strong enough to navigate at night. In the 18th century, candles and oil lamps illuminated many light fixtures in most homes and businesses. These early sources of illumination emitted a weak light, smoked, and gave off foul odors. They were also dangerous and required constant attention. Wealthy aristocrats used beeswax and spermaceti candles to light up their lavish households. The middle Lighting People 1st edition used cheap tallow candles while the poor used rushlights, makeshift candles made from reeds dipped in animal or vegetable fat and ignited, which burned Lighting People 1st edition a short time. During the 19th century, gas lighting Lighting People 1st edition candles and oil lamps in many homes, businesses, and streets. Gas lamps produced a brighter and more efficient illumination. They also cost 75 percent less than candles or oil lamps, and were easier and safer to operate. By the s, most city streets in the United States and Europe were illuminated by gas lamps. Gas lighting is credited with reducing crime rates and increasing literacy in many areas. As electricity became more widespread during the turn of the century, gas lamps were replaced by incandescent lamps in streets, businesses, and theaters. The First Electric Lights. InSir Humphry Davy, an English physician, created the first electric light by passing a current through a Lighting People 1st edition strip. InDavy demonstrated the first carbon arc lamp at the Royal Institute in London by connecting two wires to a battery and attaching a charcoal strip between the other ends of the wires. While the scientific community and the public raved about the demonstration, the arc lamp burned too brightly and consumed a large amount of current, which quickly drained the battery and rendered the lamp impractical for commercial development and production. Several decades passed before electric generators made arc lamps practical for street and theater lighting. InPavel Nikolayevich Yablochkov, a Russian electrical engineer and inventor, developed the first practical arc lamp known as the "Yablochkov Candle. Arc lamps produced an intense, bright light that was ideal for illuminating streets and outdoor spaces, but the dazzling lights were not suitable for indoor use. Lighting People 1st edition the late s, Thomas A. Edison and many other inventors began to experiment with incandescent lamps in search for a reliable and economical form of indoor lighting. Arc lamps were used for searchlights, lighthouses, stadium lights, film production lights, film projector lamps, and other high-intensity lighting applications until the s when advancements in short-arc lamps made them obsolete. The First Incandescent Light Bulbs. Incandescent light bulbs use electricity to heat Lighting People 1st edition carbon or metal base filament inside a glass bulb until it becomes hot and emits a radiant glow. A vacuum keeps the filament from burning up too quickly and blackening the interior of the glass bulb. However, these early experiments were pivotal in the development of the first commercially viable incandescent light bulb. InFrederick de Moleyns received the first patent for an incandescent lamp in England. The lamp used a glass bulb, a partial vacuum and powdered charcoal between two platinum filaments to emit light. However, the lamp was not efficient enough for commercial use. The vacuum's poor design caused the bulb to darken at the top and block light output, and the platinum filaments were too expensive. Inventors developing incandescent lamps quickly adopted the invention because it helped to preserve the filament inside the bulb. InHenry Woodward and Mathew Evans filed a patent for an incandescent light bulb with a carbon filament in Canada and the United States. The light bulbs, although they worked properly, sold poorly. They sold their patent to Thomas Edison in Lighting People 1st edition InWilliam E. Sawyer and Albion Man received the first U. The first Westinghouse light bulbs were based on the Sawyer-Man incandescent lamps. In many textbooks, Thomas A. Edison, an undisputed visionary, was not the only one competing to develop the first commercial incandescent bulb. Countless chemists, physicists, and inventors clamored for the honor and substantial payoff. Lighting People 1st editiona young Edison stated that he could create a safer, cheaper, and more reliable incandescent light to replace existing gas lights in just six weeks. The announcement caused gas company stocks to plummet. To prevent the filament from overheating and burning out, a problem that plagued earlier inventors, he created a regulating system that intermittently diverted the current away from the filament, permitting it to cool. The system was difficult to manufacture and operate, and the light bulb itself would shut off every few minutes, rendering the lamp impractical for commercial development. At the same time, Sir Joseph Wilson Swan, an English chemist and physicist, was independently working on an incandescent light bulb with a carbon filament. Swan began working on the incandescent bulb three decades earlier, but like other early inventors, he lacked a reliable vacuum and a suitable electric source to create a practical light bulb. In latehe reported to the Newcastle Chemical Society that he had created a working incandescent lamp and he received a UK patent that same year. In FebruarySwan demonstrated a working lamp during a lecture at the Newcastle Literary and Philosophical Society. His lamp design included an enclosed bulb with the air removed, platinum lead wires, and light-emitting carbon Lighting People 1st edition. The carbon rod had low electrical resistance and required a large amount of current to heat up and make the filament glow, which meant that the electric conductors to the lamp had to be short or unreasonably thick. The rod also released gasses when the lamp was turned on and dark soot quickly accumulated inside the glass, blocking light output. Swan improved his design and eventually established his own electric lighting company, The Swan Electric Light Company, in InEdison and his team discovered that a thin filament with high electrical resistance was more efficient. This meant that only a small amount of Lighting People 1st edition and reasonably sized copper cables were needed to make the filament glow. The team also experimented with carbonized filaments made from baywood, boxwood, cedar, cotton, hickory, and flax. InEdison's team improved the light bulb with a bamboo filament that burned for 1, hours. The carbonized bamboo filament became the standard filament for the next ten years. The same year, Edison received a second U. Representatives of the Edison Electric Light Company promoted the new incandescent lamps by holding demonstrations at the Menlo Park lab and attending trade shows and expositions all around the Lighting People 1st edition. The demonstrations were designed to associate Edision's name with the new lighting technology. During this time, Edison pursued legal action after Swan after mutual allegations of patent infringement. Edison bought Swan out of the company after a few years. Thomas Edison did not invent the first light bulb; however, he did improve the design and performance of the earliest incandescent lamps to create the first commercially viable Lighting People 1st edition bulb. He also developed other inventions that made the light bulb practical to for everyday use. The Edison Screw, a system of screw mounts that ensures compatibility between a light bulb and the base of a light fixture, and a complete electrical lighting system including feeders, switches and meters not only capitalized on his light bulb design, but it also made him a household name and secured his name in the history books. Edison's light bulb remained unaltered for several decades. InWilliam D. Coolidge, an American physicist at General Electric GEdeveloped tungsten filaments that lasted longer and burned brighter than carbon filaments. GE overhauled their bulb-making equipment and began selling light bulbs with tungsten filaments, replacing the carbonize bamboo filaments. InMarvin Pipkin, a American chemist and inventor, developed the frosted incandescent light bulb. Pipkin also devised a silica coating process that helped diffuse light, reduce glare, and minimize loss of light output. The halogen light bulb was first introduced in by GE. These light bulbs, while an adaptation of incandescent light bulbs, reduced the uneven evaporation of the filament and darkening of the envelope by filling the lamp with halogen gas rather than an inert gas. Halogen bulbs also lasted longer with an average life of 1, hours, and consumed 15 percent less energy. Despite numerous improvements over the years, modern incandescent bulbs remained inefficient.