Algebra.—The discoverer or the first user of algebra is unknown. It is said that Diophantus wrote it in 170 A. D., and he may have been its inventor. It was brought into Spain in about 900. Its signs are said to have been used first in 1544, but algebra did not come into common use until 1590. Descartes applied algebra to geometry in 1637.
Almanacs.—The word "almanac" is of Saxon origin, and probably the first almanac was published in 1470, and the first in English in 1673.
Amazons.—An ancient body of warlike women, ruled by a queen, who allowed no man to live with them. They were opposed to marriage and resolved to form a female state. They burned off their right breasts that they might better use the bow and javelin. This custom is the origin of the name "Amazons" or "breastless ones."
Apostles' Creed.—Considered by most Biblical students as the earliest form of Christian creed. It is attributed directly to the Apostles. It is doubtless the formula of belief that existed in all the early Latin churches. It was made a part of public worship of the Christian church at Antioch, and introduced into the Roman Catholic Church in the eleventh century, and subsequently into the Church of England.
April Fool's Day.—Its origin is unknown, but it is supposed to follow an ancient pageant custom of playing tricks on the first day of April.
Arbor Day.—A few years ago the United States and Canada officially set apart one day in the year for the planting of trees, shrubs, etc. It was the intention to have this day observed chiefly by the children of the public schools. Its observance has resulted in the planting of millions of trees.
Arithmetic.—While the inventor or discoverer of arithmetic is unknown, it is said that it was brought from Egypt into Greece in 600 B. C. Euclid is the author of the oldest treatise upon arithmetic and wrote it about 300 B. C. The arithmetic of decimals began in 1482, and the first arithmetic in English was printed in 1522.
Artesian Wells.—An artesian well is one made by boring perpendicularly into the earth. The oldest known well of this kind was sunk in Europe in 1126. Probably the most famous one is near Paris, which was bored in 1833, bringing water from a depth of 1792 feet. From this well 516 gallons of water flow per minute. In Missouri there is one well 2197 feet deep, and another nearly 4000 feet deep. The invention of the artesian well is undoubtedly due to the Chinese.
Artificial Ice.—The artificial manufacture of ice is of somewhat recent origin, and there are over 2,000 ice-making plants in the United States, exclusive of those used by breweries, packers, and others for the making of their own ice. Artificial ice-making showed an increase of 81 per cent. during the last few years.