spirit level, tool for determining whether a surface is horizontal. It consists essentially of a slightly bent transparent tube that is held in a frame. The tube contains some alcohol, ether, or similar fluid but is not entirely filled, so that it also contains a small bubble. The position of the bubble within the tube indicates whether the instrument is horizontal. The spirit level used by carpenters and masons has two tubes at right angles to each other, so that the device registers a vertical as well as a horizontal position. The plumb line was used to determine vertical position from ancient times until the 19th cent. At that time the spirit level, which was invented in France during the 17th cent., came into general use and replaced the plumb line in some applications.

Holy Spirit or Holy Ghost [ghost, i.e., spirit, a translation of Gr. pneuma=breath, air], in Christian doctrine, the third person of the Trinity. The Holy Spirit is sometimes defined as the aspect of God immanent in this world, in human beings, and in the church. Jesus' promise to his disciples of a Comforter (or Paraclete, i.e., advocate), in John 14, is considered his principal reference to the Holy Spirit, and the descent of the Holy Spirit on the apostles and the communication of the gift of tongues, as recounted in Acts 2, is thought to be an example of the work of the Holy Spirit in time. This incident is commemorated on Pentecost (Whitsunday). Certain Christian groups, such as the Montanists and the Society of Friends, have attributed utterances of their members to the inspiration of the Holy Spirit. The dove is the symbol of the Holy Spirit. For the controversy over the procession of the Holy Spirit, see creed.

or methyl alcohol or wood alcohol

Simplest of the alcohols, chemical formula CH₃OH. Once produced by destructive distillation of wood, it is now usually made from the methane in natural gas. Methanol is an important industrial material; its derivatives are used in great quantities for making a vast number of compounds, among them many important synthetic dyes, resins, drugs, and perfumes. It is also used in automotive antifreezes, in rocket fuels, and as a solvent. It is flammable and explosive. A clean-burning fuel, it may substitute (at least in part) for gasoline. It is also used for denaturation of ethanol. A violent poison, it causes blindness and eventually death when drunk.

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Alcoholic beverage obtained by distillation from wine or other fermented fruit juice or from various cereal grains that have first been brewed. The essential ingredient is usually a natural sugar or a starchy substance that may be easily converted into a sugar. The distillation process is based on the different boiling points of water (212 °F [100 °C]) and alcohol (173 °F [78.5 °C]). The alcohol vapours that arise while the fermented liquid boils are trapped and recondensed to create a liquid of much greater alcoholic strength. The resultant distillate is matured, often for several years, before it is packaged and sold. Seealso aquavit; brandy; gin; liqueur; rum; vodka; and whiskey.

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or Holy Ghost or Paraclete

In Christianity, the third person of the Holy Trinity. Though references to the spirit of Yahweh (God) abound in the Old Testament, Christian teaching about the Holy Spirit is derived mainly from the Gospels. The Holy Spirit descended on Jesus at his baptism, and outpourings of the Spirit are mentioned in the Acts of the Apostles, in which healing, prophecy, exorcism, and speaking in tongues are associated with its activity. The Holy Spirit also came to the disciples during Pentecost. The definition of the Holy Spirit as a divine person equal in substance to the Father and the Son was made at the Council of Constantinople (AD 381).

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