Some Light Reading

It is believed that early humans likely discovered how to control fire on accident. Blinded by the deepest dark in an alien world absent of street lamps, a strike of lightning could have lit a small bush and brightened the night. This serendipitous event combined with clever thinking led to an early form of technology: light. Since then, humans’ ability to harness light has progressed, and light has imbedded itself as a necessary societal tool, literally illuminating paths for humankind’s advancement. This journey contains an interesting history and fascinating trivia about light.

Early Uses of Light

Cave paintings, often deep within dark caves, offer early evidence for light usage. Some paintings were even advanced enough to confer an additional benefit for those who viewed the art with firelight. Paintings of bison and horses appear to run or dip their head in the flickering light of a torch. After the torch, which was merely fire on a stick, proved to be inadequate, light technology underwent its first progression with the advent of the lamp. These crude lamps were hollow stones or shells filled with fuel and a wick of fiber or moss. The most common fuels were animal fat (especially oily fish) or oils pressed from seeds, olives, or nuts.  It is believed that early humans also discovered how to use light reflection to their advantage. Small, artificial carvings in caves reflect light well and could be used to enhance cave drawings.

You can imagine flickering flames producing a cinematic effect.

You can imagine flickering flames producing a cinematic effect.

Early Babylon was one of the first civilizations in which there is evidence that lamps had been used. It was difficult to make lamps though. Animal fat was needed for fuel, a heat source was needed to melt the fat, and labor was needed to mold the fat and add a wick. Often, the poor would resort to animal fat or oil for sustenance, so lamps were generally seen as a luxury. Recently, economists used wage data to determine how much light cost in ancient Babylon. An entire day’s of work could purchase a mere 10 minutes of light.

Candles took longer to come about; the first candle may have appeared in China around 200 BC. These candles were made from whale fat, and many early candles were also produced with animal fat, or tallow. Wax also was used in early candles but was generally more expensive. Some plants secrete wax to keep cool in warm climates. Worker bees also produce wax to build honeycombs. One type of early wax candles was made by boiling cinnamon. Again, candle production was a costly way to provide light. It was of extremely poor quality, smelled terrible (if tallow was used), and dripped everywhere. Plus, only the rich could afford it. Now, candles are primarily a decorative item in the western world and are typically made with paraffin wax produced from petroleum.

Among these standard, well-known methods of lighting were other unorthodox attempts to harness light. Some animals produce light, a process called bioluminescence, and various societies attempted to utilize this light source. Records indicate that fireflies were commonly used by early civilizations in the West Indian Islands and in Japan. Other insects, sea creatures (famously, jellies), and some fungi can also emit light.

A bioluminescent fungus

A bioluminescent fungus

From the time of the ancient Babylonians to the 18th century, not much changed in terms of lighting technology. Lighting costs were still high, and day-to-day life was dictated by the rising and setting of the sun. Some cities attempted to defy this schedule by ordering citizens to hang lamps, and large cities like Paris and London were often well-lit at night but only at certain times of the year. In the 18th century, residents were fined if their windows did not have a lamp. However, the costs were still high, and a surging demand for lighting paved the way for new advancements.

William Murdoch and Gas Lighting

After 2000 years of nearly-stagnant light improvements, William Murdoch provided the first modern development in light technology. As a precocious youth, Murdoch excelled in mathematics and mechanics. He helped his father design bridges and developed a “wooden horse on wheels”, which was essentially a tricycle. When he was 23, he decided he wanted to work for James Watt (of steam engine fame and the namesake for how we now measure light bulb power consumption). Murdoch walked over 300 miles through the English countryside to ask for a job. It was not Murdoch’s moxie that landed him a position in the famous engineer’s factory, though. Watt’s business partner was impressed by Murdoch’s wooden hat that Murdoch had spun on a lathe he built, and Murdoch was offered a job.

Murdoch developed a reputation as an eminent inventor. He improved the steam engine, built the first working model of a steam-powered carriage (a predecessor to the car), and, most importantly, revolutionized the lighting industry. Murdoch experimented with town gas produced from heating coal. He subjected his home and family to the first experiments with gas lighting. In 1792, his home appeared ablaze from his controlled town gas lamps.

After this initial success, gas lighting proceeded to garner widespread attention. Murdoch installed 50 lights into the first gas-lit factory, which soon added 854 more lights. In less than 30 years after Murdoch’s first experiments, major cities like Paris were already implementing citywide gas lighting. Murdoch’s name might not be recognizable, even with this substantial feat. Murdoch never saw any money from his invention because he never patented his idea. He believed that gas lighting would never catch on, but that was obviously a major oversight and may be the reason he has been overlooked in history books. With the discovery of “rock gas”, or petroleum, and kerosene, lighting efficiency improved even further. Nearly 4000 years after the ancient Babylonians worked one day for 10 minutes of light, Europeans could work the same time period and get 5 hours of light.

Invention of the Light Bulb

With oil and gas also came electric power, and the invention of the light bulb was looming on the technological horizon. Many scientists at the time understood how electricity could produce light and were attempting to develop electric lamps. Electricity was being used to produce light as early as 1806. Humphrey Davy ran a current between two rods and produced a blinding light that was deemed impractical for most purposes.  Inventors of the 18th century would have to find another way to produce light.

These inventors pursued the property of incandescence. Incandescence occurs when a hot object glows, like when a blacksmith pulls iron from the furnace. Various scientists and inventors began experimenting with incandescent light bulbs. In 1882, Thomas Edison improved the technology and developed the infrastructure that demonstrated these strange “glow lamps” would be the wave of the future. Since that time period, major companies like General Electric have implemented minute changes, like replacing the filament, size, or structure. Now, light can be portable or wearable, with flashlights and glow sticks readily available. Light can be produced from wildly different sources for wildly different applications, like huge spotlights or tiny, high powered lasers.  Light efficiency has been slowly approaching a maximum, and a day’s wage can produce more than 20,000 hours of light.

He'd probably have a light bulb over his head, but he hadn't invented it yet.

He’d probably have a light bulb over his head, but he hadn’t invented it yet.

 

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One thought on “Some Light Reading

  1. Pingback: Introduction to Research: Light | Material World

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