Candle: Encyclopedia - Candle

Candle

A candle is a light source usually consisting of an internal wick which rises through the center of a column of solid fuel. Typically the fuel is some form of wax - paraffin wax being the most common. However in recent years new soy and vegetable candles have become popular.

Prior to the candle being ignited, the wick is saturated with the fuel in its solid form. The heat of the match or other flame being used to light the candle first melts and then vaporizes a small amount of the fuel. Once vaporized, the fuel combines with oxygen in the atmosphere to form a flame. This flame then provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel, the liquified fuel then moves upward through the wick via capillary action, and the liquified fuel is then vaporized to burn within the candle's flame.

The burning of the fuel takes place in several distinct regions (as evidenced by the various colors that can be seen within the candle's flame). Within the bluer, hotter regions, hydrogen is being separated from the fuel and burned to form water vapor. The brighter, yellower part of the flame is the remaining carbon soot being oxidized to form carbon dioxide.

As the mass of the solid fuel is melted and consumed, the candle grows shorter. Portions of the wick that are not evaporating the liquid fuel are themselves consumed in the flame, limiting the exposed length of the wick.

Candle - Usage

Prior to the domestication of electricity, candles were a common source of lighting, before, and later in addition to, the oil lamp. Due to local availability and the cost of resources, for several centuries up to the 19th century candles were more common in northern Europe, and olive oil lamps more common in southern Europe and around the Mediterranean Sea. Makers of candles were known as chandlers.

Today, candles are usually used for their aesthetic value, particularly to set a soft, warm, or romantic ambience, and for emergency lighting during electrical power failures. Scented candles are common in aromatherapy. Small candles are often placed on birthday cakes.

Candle - Religion

Candles are used in religious ceremonies.

See Ubon Ratchathani Candle Festival

In Christianity, they typically represent the light of God, or specificially the light of Christ, and are often placed on the altar. Votive candles may be lit as an accompaniment to prayer. Candles are lit by worshippers in front of icons in Orthodox and other churches. See also Paschal candle and Dikiri and trikiri.

Candlemas marks the end of the season of Epiphany.

Candles were traditionally used to light up Christmas trees before the advent of electric lights. They are still, even today, commonly used to decorate Christmas trees in Denmark and other European countries. They are also used in Advent wreaths.

In Sweden (and other Scandinavian countries), St. Lucia Day is celebrated on December 13 with the crowning of a young girl with a ring of candles.

In Judaism, candles are traditionally lit on Friday evening at the start of the weekly Sabbath celebration. The Jewish holiday of Hanukkah, also known as the Festival of Lights, is celebrated by lighting a candle in a special candelabrum (menorah) each night during the eight-day holiday to commemorate the dedication of the altar in the Temple in Jerusalem. Candles are also used in remembering a deceased loved one, especially on their Yahrzeit, the anniversary of their death according to the Hebrew calendar, when a 24-hour candle is lit.

Candles are also used in celebrations of Kwanzaa, which is an African American holiday which runs from December 26 to January 1.

For Humanists, skeptics, and nontheists (and particularly secular humanists), candles have become a symbol of the light of reason or rationality. This association was inspired by Carl Sagan, who subtitled his 1997 book The Demon-Haunted World with Science as a Candle in the Dark. The Humanist festival of HumanLight often features a candle-lighting ceremony.

In Wicca and related forms of Neopaganism, candles are frequently used on the altar to represent the presence of the God and Goddess, and in the four corners of a ritual circle to represent the presence of the four elements. When used in this manner, lighting and extinguishing the candles marks the opening and closing of the ritual. Candles are also frequently used by Wiccans and other Neopagans for magical and meditative purposes.

Candle - Measurement

With the fairly consistent and measurable burning of a candle a common use was to tell the time, though the accuracy is debatable. Some candles have these measurements, usually in hours, marked along the wax.

In the days leading to Christmas some people burn a set amount to represent each day, as marked on the candle. Candles used in this way are called Advent candles.

Candle - Fuel and candle holders

Candles can be made of paraffin (a byproduct of petroleum refining), stearin (now produced almost exclusively from palm waxes), beeswax (a byproduct of honey collection), gel (a mixture of resin and mineral oil), some plant waxes (generally palm, carnauba, bayberry, or soy), or tallow (a rarely used byproduct of beef fat rendering). Candles are produced in various colors, shapes, sizes and scents. The most basic production method generally entails the liquification of the solid fuel by the controlled application of heat. This liquid is then poured into a mold to produce pillar candles, a fireproof jar to produce container candles, or a wick is repeatedly immersed in the liquid to create a dipped taper. Often, fragrance oils are added to the liquid wax prior to pouring. Natural scents, in the form of essential oils, can be used, but these are usually only found in premium, small-run candles. Candles may also be colored by the addition of some sort of coloring agent. In practical terms this is almost always an aniline-based dye, although pigments can be used in some circumstances.

A candle typically produces about 12.6 lumens of visible light and 40 watts of heat [1], although this can vary depending primarily on the characteristics of the candle wick. For comparison, note that a 40 watt incandescent light bulb produces approximately 500 lumens for the same amount of power. The unit candela was originally defined to indicate the 'brightness' of a naked candle flame.

It is commonly believed candles made of beeswax and/or soy burn more cleanly than petroleum based paraffin waxes. The amount of soot produced by a candle, independent of what kind of wax is used, is generally more dependent on environmental conditions (drafts will often cause sooting) and the type of wick used (a poorly sized wick will lead to sooting). The inclusion of any scents and/or dyes will increase the amount of particulates put into the air by any candle regardless of construction materials. The cleanest burning candles will therefore be unscented, undyed, and well constructed candles burning in a draft free area.

Decorative candle holders, especially those shaped as a pedestal, are called candlesticks; if multiple candles are held, the term candelabrum is also used. The root form of chandelier is from the word for candle, though candles are rarely raised and hung today.

Candle - Hazards

Candles are a major cause of damaging fire in households.

A former worry regarding the safety of candles was that a lead core is used in the wicks in order to keep the wicks upright in container candles. Without a stiff core, the wicks of container candles would sag and drown in the deep wax pool formed. The fear was that the lead in these wicks would vaporize during the burning process and release lead vapours - a known health and developmental hazard. While this was true at one time, lead-cored wicks have not been in common use since the 1970s. While some very small percentage of candles might still be found to have lead cored wicks, these are extremely rare. Most metal-cored wicks use zinc or a zinc alloy. Wicks made from specially treated paper and cotton are also used to replace metal-cored wicks of any type. Still, caution should be used with candles fabricated in countries without regulations regarding lead-cored wicks.

See also

• Rushlight
• Timeline of lighting technology
• History of candle making
• The candela (symbol: cd, Latin for candle) is one of the seven SI base units measuring the luminous intensity. it supersedes the former candlepower.

Adapted from the Wikipedia article "Candle", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki