Lighting

Ancient Lighting

Lamps have existed from ancient times. An example is the Inuit oil lamps, admired for their wide range of heat and light, a by-product of the relationship between hunter and prey that provided critical fuel for heat and light for people living beyond the Arctic Circle year-round.

As early as 5,000 years ago, architecture became formalized for a significant section of cities, and the desire and need for rooms to have lighting after nightfall led to a market for early candle factories. This also extended to fine oils for lamps. Resources for these lighting products are examples of early biofuel use and came from cattle and other animals as tallow, a waxy fat, and from certain plants from which burnable oils were pressed. Waxes were learned about over time and incorporated as the major component by many candle makers, along with scents and specialty wicks from certain fibers.

Candles can be made in sizes that burn in tens of days, or are gone in minutes, and, while ancient [Page 475]in technology, are still preferred for the atmosphere they deliver as they illuminate for an intimate meal or other gathering.

Industrial Age

Candles were not very practical for the steam-powered Industrial Age. Cities have long been susceptible to fires that spread catastrophically. The Industrial Age brought new fuels, including gases, and also brought many refinements. These improvements came in the form of woven wicks, reflectors, glass globes and lamps with control of both oil and air, and, most important, with lenses, a practical way to control beams of light. Light physics is tied to lighting and illumination, and lenses became a way to amplify the effectiveness of the lumens by defining the focal length and shape for a desired purpose.

Early Industrial Age light physics produced focusing and diffusing lenses and mirrors, then the Fresnel lens design. This lens is so efficient in the parallelization of light from an oil lamp or candle that it quickly became a standard in lighthouses to extend their feeble flame into the night. Good use can be made with this design today in solar collectors, concentrating the light and producing 1,315 degrees Celsius/2,400 degrees Fahrenheit temperatures on a clear day from a thin plastic lens of 2 square meters, with output about 750 watts at the focal point, 2.5 cm in diameter.

With early direct current (DC) came the solution lab battery, then a damp mixture called a “dry-cell,” a self-contained battery in a casing common as a 6-volt size, so reliable and efficient that even today they are used globally. These early batteries, and others that ended up powering the electric hand torch in sizes from AAA to D, supplied an eager, growing industrial society where electric lighting allowed processes to continue through the night. But these needed a bulb.

Thomas Alva Edison is a name still known for electricity, and his development of the incandescent light bulb was the major event in modern lighting. His lightbulbs soon became widespread for a variety of uses, from room lights to street lights, replacing the gas lamps of the era, and then made into small hand torches.

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