heal-all: see self-heal.

All-American Canal, 80 mi (129 km) long, SE Calif.; part of the federal irrigation system of the Hoover Dam. Built between 1934 and 1940 across the Colorado Desert, the canal is entirely within the United States and replaces the Inter-California Canal, which passes through Mexico. The Imperial Dam, NE of Yuma, Ariz., diverts water from the Colorado River into the All-American Canal, which runs W to Calexico, Calif. Smaller canals move water into the Imperial Valley; the Coachella Canal branches NW to the Coachella Valley. This canal system irrigates more than 630,000 acres (254,961 hectares) and has greatly increased crop yield in the area; however, problems of drainage and salinity exist.

All Souls' Day, Nov. 2 (exceptionally, Nov. 3), feast of the Roman Catholic Church on which the church on earth prays for the souls of the faithful departed still suffering in purgatory. The proper office is of the dead, and the Mass is a requiem. General intercessions for the dead (e.g., for those of a parish, a city, or a regiment) are very ancient (2 Mac. 12.43-45); but the modern feast was probably first established by Abbot Odilo of Cluny (d. 1049) for his community and later extended throughout the church. In Catholic countries there are many customs peculiar to All Souls' Day (e.g., leaving lights in the cemeteries on the night before). These vary from region to region. They should be distinguished from the customs of Halloween, which were apparently an independent development (see All Saints' Day).

All Saints' Day, feast of the Roman Catholic and Anglican churches, and day on which churches glorify God for all God's saints, known and unknown. It is celebrated on Nov. 1 in the West, since Pope Gregory IV ordered its church-wide observance in 837. Its origin lies earlier in the common commemorations of martyrs who died in groups or whose names were unknown, which were held on various days in different parts of the Church; over time these celebrations came to include not only the martyrs but all saints. During the Reformation the Protestant churches understood "saints" in its New Testament usage as including all believers and reinterpreted the feast of All Saints as a celebration of the unity of the entire Church. In medieval England the festival was known as All Hallows, hence the name Halloween [=All Hallows' eve] for the preceding evening.

All Saints Bay, Brazil: see Todos os Santos Bay.

In the Roman Catholic church, a day commemorating all the Christians believed to be in purgatory. Celebrated on November 2, it was first established by Odilo (d. 1049), abbot of Cluny, in the 11th century, and it was widely celebrated by the 13th century. The date follows All Saints' Day, with the idea that remembering the saints in heaven should be followed by remembering the souls awaiting release from purgatory. Roman Catholic doctrine holds that the prayers of the faithful on earth will help cleanse these souls in order to prepare them for heaven.

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In Christianity, a day commemorating all the saints of the church, known and unknown. It is celebrated on November 1 in the Western churches and on the first Sunday after Pentecost in the Eastern churches. The first general observance of All Saints' Day was ordered by Pope Gregory IV in 837. In medieval England the festival was called All Hallows, and its eve is still known as Halloween.

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