of the psalm in groups of three or four verses respectively. Psalm 2 (for example) is suited to a triple chant; a quadruple chant might be used for Psalm 78. A double chant is divided into "quarters", each of which has the music for half a verse. Triple and quadruple chants may also be described as containing six or eight quarters. If the entire text (or a section of it) has an odd number of verses, the second half of the chant is usually repeated at an appropriate point, which may be marked "2nd part". Similarly, "3rd part" markings may be used for triple chants. An example of a double chant: Below are the four lines of the doxology Gloria Patri (commonly known as the "Gloria"), with the text coloured to show which words correspond to which notes in the music (pointing varies from choir to choir): Glory be to the Father, and ' to the ' Son : and ' to the ' Holy ' Ghost; As it was in the beginning, is now, and ' ever ' shall be : world without ' end A ' - - ' men. The doxology Gloria Patri, usually sung at the end of a psalm or canticle, is two verses long. Depending on the type of chant, it is sung in one of the following ways: to a single chant sung twice, to a double chant, to an appropriate 14 bars (usually specified by the composer) of a triple chant or quadruple chant. Accompaniment Psalms may be sung unaccompanied or accompanied by an organ or other instrument. Organists use a variety of registrations to mirror the changing mood of the words from verse to verse; but the organ should never be so loud that the words cannot be clearly heard. Organists may sometimes indulge in word painting, using effects such as a deep pedal note on the word "thunder", or a harsh reed tone for "darkness" contrasting with a mixture for "light". Antiphonal singing A further stylistic technique is used in cathedrals and churches which use an antiphonal style of singing. In this case, the choir is divided into two equal half-choirs, each having representation for the four musical parts, and usually facing one another. They are typically named Decani (usually the half-choir to the south side) and Cantoris (usually the half-choir to the north side). Then the choir may employ