According to mythology, the first person to actually see an image of himself was the Greek hunter, Narcissus. Narcissus was widely known for being one of the handsomest lads in the kingdom, and caught the attention of many an amorous maid, including an ardent wood spirit named, Echo. Echo pursued Narcissus, but he had seen a himself in a still pond, and fell in love with his own reflection. The long and short of the story is that Narcissus refused to leave his reflection even to eat, so starved to death. Grief-stricken Echo pined away until only her voice remained.
Fast forward around 8000 years (to 6000 BC) to Anatolia (modern-day Turkey.) Upper crust women of the period gazed at their likenesses using mirrors made from a volcanic glass called, obsidian. A couple of thousand years later, in Mesopotamia, polished copper made its appearance, and about a thousand years after that Egyptians began using many different types of highly polished metal, including silver.
These stone and metal mirrors could be made in very large sizes, but were difficult to polish and get perfectly flat; a process that became more difficult as size increased, so they often produced warped or blurred images. Stone mirrors often had poor reflectivity compared to metals, yet metals scratch or tarnish easily, so they frequently needed polishing. Depending upon the color, both often yielded reflections with poor color rendering. The poor image quality of ancient mirrors explains Paul’s comment in Corinthians “…we see through a glass darkly.”
Historians think that sometime during the first century AD glass mirrors appeared, eventually spreading throughout the Roman Empire. Mirrors began to be better reflectors after the Romans started finishing them with a metal layer. The earliest glass made mirrors were only about three inches in diameter and mirrors manufactured from metal were still preferable by many people due to the fact that glass mirrors still did not have a very good reflection. They became more popular after the invention of a technique which allowed glass manufacturers to make flat thin glass and spread hot metal onto the glass without breaking it. The first mirrors were used almost exclusively by the ruling classes.
In China, people began making mirrors by coating metallic objects with silver-mercury amalgams as early as 500 AD. This was accomplished by coating the mirror with the amalgam, and then heating it until the mercury boiled away, leaving only the silver behind.
The problems of making metal-coated, glass mirrors was due to the difficulties in making glass that was very clear, as most ancient glass was tinted green from iron. This was overcome when people began mixing soda, limestone, potash, manganese, and fern ashes with the glass. There was also no way for the ancients to make flat panes of glass with uniform thicknesses. The earliest methods for producing glass panes began in France, when people began blowing glass bubbles, and then spinning them rapidly to flatten them out into plates from which pieces could be cut. However, these pieces were still not uniform in thickness, so produced distorted images as well. A better method was to blow a cylinder of glass, cut off the ends, slice it down the center, and unroll it onto a flat hearth. This method produced the first mirror-quality glass panes, but it was very difficult and resulted in a lot of breakage. Even windows were primarily made of oiled paper or stained glass, until the mid-nineteenth century, due to the high cost of making clear, flat panes of glass.
Making flat panes of clear glass from blown cylinders began in Germany and evolved through the Middle Ages, until being perfected by the Venetians in the sixteenth century. The Venetians began using lead glass for its crystal-clarity and its easier workability. Some time during the early Renaissance, European manufacturers perfected a superior method of coating glass with a tin-mercury amalgam, producing an amorphous coating with better reflectivity than crystalline metals and causing little thermal shock to the glass. The exact date and location of the discovery is unknown, but in the sixteenth century, Venice, a city famed for its glass-making expertise, became a center of mirror production using this new technique. Glass mirrors from this period were extremely expensive luxuries. For example, in the late seventeenth century, a French Countess was reported to have traded an entire wheat farm for a mirror, considering it a bargain. These Venetian mirrors were limited in size to a maximum area of around 40 square inches, until modern glass panes began to be produced during the Industrial Revolution.
The invention of the silvered-glass mirror is credited to German chemist Justus von Liebig in 1835. His process involved the deposition of a thin layer of metallic silver onto glass through the chemical reduction of silver nitrate. This silvering process was adaptable to mass manufacturing, and led to the greater availability of affordable mirrors.
By the way, the word “mirror” comes from the Latin word, mirari, meaning to admire. The Romans called theirs a speculum, meaning to look.
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