Lampshade

A lampshade is a fixture that covers the lightbulb on a lamp to diffuse the light it emits. Conical, cylindrical and other forms on floor-, desk- or table top-mounted as well as suspended lamp models are the most common and are made in a wide range of materials. The term can also apply to the glass hung under many designs of ceiling lamp. Beyond its practical purpose, significant emphasis is also usually given to decorative and aesthetic features.

In the late 17th-century in Paris the first public lanterns made their appearance in the centre of the streets. They lit the road during the night. In 1763, the réverbères made their appearance. These were oil lamps with reflectors which were hung above the center of streets. The first public oil lamps in Milan, financed by revenues from a lottery, date from 1785. These were lanterns containing an oil lamp with a number of wicks. A semi-spherical reflector above the flame projected the light downwards, while another reflector, slightly concave and near the flame, served to direct the light latterly.

Friedrich Albert Winsor first had the idea of industrialising lighting by producing gas in a factory and distributing it through a pipeline. In the first decades of the 19th century, competing gas companies laid the first gas mains in major cities. But there were fears of explosion and toxicity.

The flame fed by the gas coming out of the nozzle was intense, uniform and adjustable, white and brilliant instead of the reddish or orange of oil lamps or candles.

The drawbacks of gas lighting were overheating of the air and extremely high oxygen consumption, making it necessary to ventilate the room or isolate the flame by separating the room where the combustion took place from the room being lit. Theatre audiences regularly suffered from headaches and the sulphur and ammonia formed during combustion of the gas ruined furniture.

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