This is a small square or oblong chamber in the body of the altar, in which are placed, according to the "Pontificale Romanum" (De Eccles. Consecratione) the relics of two canonized martyrs although the Cong. Sac. Rit. (16 February, 1906) decided that if the relic of only one martyr is placed in it the consecration is valid, to these may be properly added the relics of other saints, especially of those in whose honour the church of the altar is consecrated. These relics must be actual portions of the saints' bodies, not simply of their garments or of other objects which they may have used or touched; the relics must, moreover be authenticated. If the altar is a fixed or immovable altar, the relics are placed in a reliquary of lead, silver, or gold, which should be large enough to contain, besides the relics, three grains of incense and a small piece of parchment on which is written an attest of the consecration. This parchment is usually enclosed in a crystal vessel or small vial, to prevent its decomposition. The size of the cavity varies to suit the size of the reliquary. If it is a portable altar the relics and the grains of incense are placed immediately, i.e. without a reliquary, into the cavity. This cavity must be hewn in the natural stone of the altar. Hence, unless the altar be a single block of stone, a block of natural stone is inserted for the purpose in the support. The location of the cavity in a fixed altar is
APA citation. (1907). Altar Cavity. In The Catholic Encyclopedia. New York: Robert Appleton Company. http://www.newadvent.org/cathen/01351d.htm
MLA citation. "Altar Cavity." The Catholic Encyclopedia. Vol. 1. New York: Robert Appleton Company, 1907. <http://www.newadvent.org/cathen/01351d.htm>.
Transcription. This article was transcribed for New Advent by Michael C. Tinkler.
Ecclesiastical approbation. Nihil Obstat. March 1, 1907. Remy Lafort, S.T.D., Censor. Imprimatur. +John Cardinal Farley, Archbishop of New York.
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