common-law marriage: see under husband and wife.

common-ion effect, decrease in solubility of an ionic salt, i.e., one that dissociates in solution into its ions, caused by the presence in solution of another solute that contains one of the same ions as the salt. The common-ion effect is an example of chemical equilibrium. For example, silver chloride, AgCl, is a slightly soluble salt that in solution dissociates into the ions Ag⁺ and Cl^-, the equilibrium state being represented by the equation AgCl_solid ⇌Ag⁺+Cl^-. According to Le Châtelier's principle, when a stress is placed on a system in equilibrium, the system responds by tending to reduce that stress. In the system taken as an example, if another solute containing one of those ions is added, e.g., sodium chloride, NaCl, which supplies Cl^- ions, the solubility equilibrium of the solution will be shifted to remove more Cl^- from the solution, so that at the new equilibrium point there will be fewer Ag⁺ ions in solution and more AgCl precipitated out as a solid.

common law, system of law that prevails in England and in countries colonized by England. The name is derived from the medieval theory that the law administered by the king's courts represented the common custom of the realm, as opposed to the custom of local jurisdiction that was applied in local or manorial courts. In its early development common law was largely a product of three English courts—King's Bench, Exchequer, and the Court of Common Pleas—which competed successfully against other courts for jurisdiction and developed a distinctive body of doctrine. The term "common law" is also used to mean the traditional, precedent-based element in the law of any common-law jurisdiction, as opposed to its statutory law or legislation (see statute), and also to signify that part of the legal system that did not develop out of equity, maritime law, or other special branches of practice.

All Canada except Quebec and all of the United States except Louisiana follow common law. U.S. state statutes usually provide that the common law, equity, and statutes in effect in England in 1603, the first year of the reign of James I, shall be deemed part of the law of the jurisdiction. Later decisions of English courts have only persuasive authority.

Characteristic Features of Common Law

The distinctive feature of common law is that it represents the law of the courts as expressed in judicial decisions. The grounds for deciding cases are found in precedents provided by past decisions, as contrasted to the civil law system, which is based on statutes and prescribed texts. Besides the system of judicial precedents, other characteristics of common law are trial by jury and the doctrine of the supremacy of the law. Originally, supremacy of the law meant that not even the king was above the law; today it means that acts of governmental agencies are subject to scrutiny in ordinary legal proceedings.

Judicial precedents derive their force from the doctrine of stare decisis [Lat.,=stand by the decided matter], i.e., that the previous decisions of the highest court in the jurisdiction are binding on all other courts in the jurisdiction. Changing conditions, however, soon make most decisions inapplicable except as a basis for analogy, and a court must therefore often look to the judicial experience of the rest of the English-speaking world. This gives the system flexibility, while general acceptance of certain authoritative materials provides a degree of stability. Nevertheless, in many instances, the courts have failed to keep pace with social developments and it has become necessary to enact statutes to bring about needed changes; indeed, in recent years statutes have superseded much of common law, notably in the fields of commercial, administrative, and criminal law. Typically, however, in statutory interpretation the courts have recourse to the doctrines of common law. Thus increased legislation has limited but has not ended judicial supremacy.

Development of Common Law

Early common law was somewhat inflexible; it would not adjudicate a case that did not fall precisely under the purview of a particular writ and had an unwieldy set of procedural rules. Except for a few types of lawsuits in which the object was to recover real or personal property, the only remedy provided was money damages; the body of legal principles known as equity evolved partly to overcome these deficiencies. Until comparatively recent times there was a sharp division between common law (or legal jurisprudence) and equity (or equitable jurisprudence). In 1848 the state of New York enacted a code of civil procedure (drafted by David Dudley Field) that merged law and equity into one jurisdiction. Thenceforth, actions at law and suits in equity were to be administered in the same courts and under the same procedure. The Field code reforms were adopted by most states of the United States, by the federal government, and by Great Britain (in the Judicature Act of 1873).

cold, common, acute viral infection of the mucous membranes of the nose and throat, often involving the sinuses. The typical sore throat, sneezing, and fatigue may be accompanied by body aches, headache, low fever, and chills. The congested and discharging mucous membrane may become a fertile ground for a secondary bacterial invasion that can spread to the larynx, bronchi, lungs, or ears. Uncomplicated infections usually last from three to ten days.

The cold is the most common human ailment. Most adult Americans suffer from one to four colds per year, but children ages one to five—who are the most susceptible—typically may contract as many as eight. Colds are spread by respiratory droplets or by contaminated hands or objects. Although the incidence of colds is higher in winter, exposure to chilling or dampness is considered to be of little significance.

Any one of up to 200 viruses (such as the rhinoviruses, coronaviruses, or respiratory syncytial virus [RSV]) can cause colds, to which it seems almost no one is immune. Infection with a viral strain confers only temporary immunity to that strain. Colds in infants and young children caused by RSV can progress to pneumonia and other complications, especially in those under a year old who were born prematurely or have chronic lung disease; RSV causes an estimated 4,500 deaths yearly in these groups in the United States.

There is no treatment for the common cold other than that aimed at relieving symptoms and keeping the body well-rested, -fed, and -hydrated. Because of the growing problem of drug resistance, doctors are being discouraged from prescribing antibiotics (which do not affect viruses) for colds unless secondary bacterial infection makes them necessary. There is no convincing evidence that vitamin C megadoses can prevent the common cold.

Researchers have reported reduction or prevention of cold symptoms in human tests of an experimental drug against rhinoviruses, which cause nearly half of all colds. The drug acts by imitating a molecule in the body called ICAM-1, to which the rhinovirus attaches to produce colds. As rhinoviruses attach to the decoy molecules instead, the likelihood or severity of infection is decreased.

Southern Common Market: see Mercosur.

Prayer, Book of Common: see Book of Common Prayer.

Solid	Volume1
cube	l3
right rectangular parallelepiped	lwh
prism	Bh
right circular cylinder	πr2h
pyramid	1/3Bh
right circular cone	1/3πr2h
sphere	4/3πr3

1 Abbreviations: B = area of base; h = height; r = radius; l = length; w = width.

Length

Metric System

1 millimeter = 1/1,000 meter

1 centimeter = 1/100 meter

1 decimeter = 1/10 meter

1 meter (basic unit of length)

1 dekameter = 10 meters

1 kilometer = 1,000 meters

American and British Units

1 inch = 1/36 yard = 1/12 foot

1 foot = 1/3 yard

1 yard (basic unit of length)

1 rod = 51/2 yards

1 furlong = 220 yards = 40 rods

1 mile = 1,760 yards = 5,280 feet

1 fathom = 6 feet

1 nautical mile = 6,076.1 feet

Conversion Factors

1 centimeter = 0.39 inch

1 inch = 2.54 centimeters

1 meter = 39.37 inches

1 foot = 0.305 meter

1 meter = 3.28 feet

1 yard = 0.914 meter

1 meter = 1.094 yards

1 kilometer = 0.62 mile

1 mile = 1.609 kilometers

Area

Metric System

1 square centimeter = 1/10,000 square meter

1 square decimeter = 1/100 square meter

1 square meter (basic unit of area)

1 are = 100 square meters

1 hectare = 10,000 square meters = 100 ares

1 square kilometer = 1,000,000 square meters

American and British Units

1 square inch = 1/1,296 square yard = 1/144 square foot

1 square foot = 1/9 square yard

1 square yard (basic unit of area)

1 square rod = 301/4 square yards

1 acre = 4,840 square yards = 160 square rods

1 square mile = 3,097,600 square yards = 640 acres

Conversion Factors

1 square centimeter = 0.155 square inch

1 square inch = 6.45 square centimeters

1 acre = 0.405 hectare

1 hectare = 2.47 acres

1 square kilometer = 0.386 square mile

1 square mile = 2.59 square kilometers

Volume and Capacity (Liquid and Dry)

Metric System

1 cubic centimeter = 1/1,000,000 cubic meter

1 cubic decimeter = 1/1,000 cubic meter

1 cubic meter = 1 stere (basic unit of volume)

1 milliliter = 1/1,000 liter = 1 cubic centimeter

1 centiliter = 1/100 liter

1 deciliter = 1/10 liter

1 liter = 1 cubic decimeter (basic unit of capacity)

1 dekaliter = 10 liters

1 hectoliter = 100 liters = 1/10 cubic meter

American and British Units

1 cubic inch = 1/46,656 cubic yard = 1/1,728 cubic foot

1 cubic foot = 1/27 cubic yard

1 cubic yard (basic unit of volume)

1 U.S. fluid ounce = 1/128 U.S. gallon = 1/16 U.S. pint

1 British imperial fluid ounce = 1/160 imperial gallon = 1/20 imperial pint

1 pint = 1/8 gallon = 1/2 quart

1 quart = 1/4 gallon

1 U.S. gallon (basic unit of liquid capacity in the United States) = 231 cubic inches

1 imperial gallon (basic unit of liquid capacity in some Commonwealth nations) = 277.4 cubic inches

1 dry pint = 1/64 bushel = 1/2 dry quart

1 dry quart = 1/32 bushel = 1/8 peck

1 peck = 1/4 bushel

1 U.S. bushel (basic unit of dry capacity in the United States) = 2,150.4 cubic inches

1 imperial bushel (basic unit of dry capacity in some Commonwealth nations) = 2,219.4 cubic inches

Conversion Factors

1 cubic centimeter = 0.06 cubic inch

1 cubic inch = 16.4 cubic centimeters

1 cubic yard = 0.765 cubic meter

1 cubic meter = 1.3 cubic yards

1 milliliter = 0.034 fluid ounce

1 fluid ounce = 29.6 milliliters

1 U.S. quart = 0.946 liter

1 liter = 1.06 U.S. quarts

1 U.S. gallon = 3.8 liters

1 imperial gallon = 1.2 U.S. gallons = 4.5 liters

1 liter = 0.9 dry quart

1 dry quart = 1.1 liters

1 dekaliter = 0.28 U.S. bushel

1 U.S. bushel = 0.97 imperial bushel = 3.5 dekaliters

Weight (Mass)

Metric System

1 milligram = 1/1,000,000 kilogram = 1/1,000 gram

1 centigram = 1/100,000 kilogram = 1/100 gram

1 decigram = 1/10,000 kilogram = 1/10 gram

1 gram = 1/1,000 kilogram

1 dekagram = 1/100 kilogram = 10 grams

1 hectogram = 1/10 kilogram = 100 grams

1 kilogram (basic unit of weight or mass)

1 metric ton = 1,000 kilograms

American and British Units: Avoirdupois

1 grain = 1/7,000 pound = 1/437.5 ounce

1 dram = 1/256 pound = 1/16 ounce

1 ounce = 1/16 pound

1 pound (basic unit of weight or mass)

1 short hundredweight = 100 pounds

1 long hundredweight = 112 pounds

1 short ton = 2,000 pounds

1 long ton = 2,240 pounds

American and British Units: Troy and Apothecaries'

1 grain = 1/7,000 avoirdupois pound = 1/5,760 troy or apothecaries' pound

1 apothecaries' scruple = 20 grains = 1/3 dram

1 pennyweight = 24 grains = 1/20 troy ounce

1 apothecaries' dram = 60 grains = 1/8 apothecaries' ounce

1 troy or apothecaries' ounce = 480 grains = 1/12 troy or apothecaries' pound

1 troy or apothecaries' pound = 5,760 grains = 5,760/7,000 avoirdupois pound

Conversion Factors

1 milligram = 0.015 grain

1 grain = 64.8 milligrams

1 gram = 0.035 avoirdupois ounce

1 avoirdupois ounce = 28.35 grams

1 troy or apothecaries' pound = 0.82 avoirdupois pound = 0.37 kilogram

1 avoirdupois pound = 1.2 troy or apothecaries' pounds = 0.45 kilogram

1 kilogram = 2.205 avoirdupois pounds

1 short ton = 0.9 metric ton

1 metric ton = 1.1 short tons

Common Market of the South: see Mercosur.

Common Market: see European Economic Community.

Common Cause, U.S. organization that seeks a "reordering of national priorities and revitalization of the public process to make our political and governmental institutions more responsive to the needs of the nation and its citizens." Established in 1970 by John W. Gardner, it succeeded the Urban Coalition Action Council, founded in 1968. Common Cause supports a large number of political reforms, including campaign finance reform, government ethics and accountability, and nuclear control agreements. It has sponsored voter registration drives nation-wide and has worked for a liberalization of voting registration. Common Cause has used ads, computerized Federal Election Commission records, lobbying, media outreach and especially litigation to promote reform. Its legal actions helped force disclosure of individuals and corporations that had anonymously contributed money to the 1972 presidential campaign. In 1991 its ad campaign, aimed at toughening a campaign finance bill containing no aggregate limit on PAC money for Congressmen, criticized Democratic Congressmen for collecting special interest money for campaigns. Located in Washington, D.C., the group has about 200,000 members.

Central American Common Market (CACM), trade organization envisioned by a 1960 treaty between Guatemala, Honduras, Nicaragua, and El Salvador. The treaty established (1961) a secretariat for Central American economic integration, which Costa Rica joined in 1963; Panama now has observer status in some areas. By 1970 trade between member nations had risen more than tenfold over 1960 levels, and imports doubled and a common tariff was established for 98% of the trade with nonmember countries. However, the 1969 war between El Salvador and Honduras led to the latter's effective withdrawal, and the political turmoil in Central America during the 1970s and 80s left the organization moribund. The 1990s saw a revival of the organization, but its ultimate place with respect to the Central American Free Trade Agreement (signed 2004, and including the Dominican Republic and the United States) and the proposed (2001) Free Trade Area of the Americas is unclear.

Caribbean Community and Common Market (CARICOM), organization founded by the Treaty of Chaguaramas (Trinidad; 1973, revised 2001) and including Antigua and Barbuda, Bahamas, Barbados, Belize, Dominica, Grenada, Guyana, Haiti (suspended 2004-6), Jamaica, Montserrat, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Suriname, and Trinidad and Tobago. Anguilla, Bermuda, the British Virgin Islands, the Cayman Islands, and the Turks and Caicos Islands are associate members. Its purpose is to promote economic integration and development, especially in less-developed areas of the region. Besides managing a common market, CARICOM formulates policies regarding health, education, labor, science and technology, tourism, foreign policy, and the environment. CARICOM's headquarters are in Georgetown, Guyana. In 2005 the organization established the Caribbean Court of Justice, which functions for participating nations as a final court of appeals and as a court of original jurisdiction for settling disputes among CARICOM nations. In 2006 Caricom inaugurated its single market and economy when six of its members participated in the establishment of a CARICOM single market. The establishment of a single economy for participating nations is planned for 2008. Other affiliated institutions include the Caribbean Development Bank, the Univ. of Guyana, and the Univ. of the West Indies.

Brothers of the Common Life: see Groote, Gerard.

Book of Common Prayer, title given to the service book used in the Church of England and in other churches of the Anglican Communion. The first complete English Book of Common Prayer was produced, mainly by Thomas Cranmer, in 1549 under Edward VI. Essentially it was a selection and translation from the breviary and the missal, with some additions from other sources. It was made compulsory by the Act of Uniformity (1549). Revision, undertaken by Cranmer, resulted in the Prayer Book of 1552, which showed the influence of foreign reformers then resident in England, for it made possible a wide diversity of views regarding the Eucharist, all justified by this official service book. The prayer book was in use only about eight months before Queen Mary's repeal legislation restored Roman Catholicism in England. In 1559, under Elizabeth I, the Prayer Book of 1552 was restored in a slightly altered version. From 1645 to 1660, under the Commonwealth and Protectorate, the prayer book was suppressed. In a new revision after the Restoration, it was again declared the only legal service book for use in England by an Act of Uniformity (1662). Alterations in the 1662 revision were largely those making for liturgical improvement. In 1927 a revised form was submitted to Parliament, whose approval was (and is) still required, and passed by the House of Lords but rejected by the Commons; it was resubmitted (with certain modifications) in 1928 and again rejected. Nonetheless, the revised prayer book was quite widely adopted in the Church of England with episcopal approval. This situation was finally legalized by the Prayer Book Measure, passed by Parliament in 1965. In addition to authorizing revisions already in use, the act approved the experimental use of new forms of worship drawn up by a liturgical commission; the Alternative Service Book (ASB) was adopted in 1980 and authorized for use alongside the Book of Common Prayer until the end of 2000. Revision of ASB is underway and under the general title Common Worship some revisions have already been authorized and published. In 1789, when the first General Convention of the Episcopal Church in the United States met, a revised version of the Book of Common Prayer was adopted; it embodied such changes as were required by the new conditions. In the U.S. Episcopal Church, as in other churches of the Anglican Communion over which the British Parliament has no control, there has been greater freedom in liturgical revision; the last U.S. revision of the Book of Common Prayer was in 1979.

Marriage that is without a civil or religious ceremony and is based on the parties' agreement to consider themselves married and usually also on their cohabitation for a period of time. Most jurisdictions no longer allow this type of marriage to be formed, though they may recognize such marriages formed before a certain date or formed in a jurisdiction that permits such marriages.

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Nonmigratory, earless seal (Phoca vitulina) found throughout the Northern Hemisphere. Harbour seals are whitish or grayish at birth, generally gray with black spots as adults. The adult male may reach a length of about 6 ft (1.8 m) and a weight of almost 300 lb (130 kg); the female is somewhat smaller. Found along coastlines and in a few freshwater lakes in Canada and Alaska, the harbour seal is a gregarious animal that feeds on fish, squid, and crustaceans. It is of little economic value and in some areas is considered a nuisance by fishermen.

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Aromatic perennial herb (Salvia officinalis) of the mint family, native to the Mediterranean. Its leaves are used fresh or dried as a flavouring in many foods. The stems, 2 ft (60 cm) tall, have rough or wrinkled, downy, gray-green or whitish green oval leaves. The flowers may be purple, pink, white, or red. Since the Middle Ages, sage tea has been brewed as a spring tonic and a stimulant believed to strengthen the memory and promote wisdom. Seealso salvia.

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(born Aug. 4, 1816, Shenandoah, N.Y., U.S.—died July 22, 1906, Lawrence Beach, N.Y.) U.S. financier. He worked as an errand boy, studying arithmetic and bookkeeping in his spare time, and in 1839 he started a wholesale grocery business, which earned him enough money to start a Hudson River shipping trade. He served in Congress (1853–57). Sage invested successfully in the La Crosse Railroad in Wisconsin, and he eventually acquired an interest in more than 40 railroads, serving as director or president of 20. He helped organize the Atlantic & Pacific Telegraph Co. In 1872 he originated stock-market puts and calls (options to buy or sell a set amount of stock at a set price and within a given time limit), but he stopped dealing in them after losing $7 million in the panic of 1884. His wife, Margaret Olivia Sage, established the Russell Sage Foundation and Russell Sage College (Troy, N.Y.) after his death.

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or finback whale or razorback whale or common rorqual

Swift, slender-bodied baleen whale (Balaenoptera physalus) named for the ridge on its back. It is 59–89 ft (18–27 m) long, with a triangular dorsal fin, short baleen, and several dozen grooves along its throat and chest. It is gray, with white on the underparts and on the right side of the lower jaw. It is found in oceans worldwide, in groups of a few to several hundred. It lives in polar waters in summer, feeding on crustaceans and small fishes, and moves to warmer waters in winter to breed. Once commercially valuable, it has been substantially reduced in numbers by overhunting and is now listed as an endangered species.

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Body of law based on custom and general principles and that, embodied in case law, serves as precedent or is applied to situations not covered by statute. Under the common-law system, when a court decides and reports its decision concerning a particular case, the case becomes part of the body of law and can be used in later cases involving similar matters. This use of precedents is known as stare decisis. Common law has been administered in the courts of England since the Middle Ages; it is also found in the U.S. and in most of the British Commonwealth. It is distinguished from civil law.

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Any plant of the genus Ficus, in the mulberry family, especially Ficus carica, the common fig. Yielding the well-known figs of commerce, F. carica is native to an area from Asiatic Turkey to northern India, but natural seedlings grow in most Mediterranean countries, where figs are used extensively, both fresh and dried. It is a bush or small tree with broad, rough, deciduous leaves (see deciduous tree). Hundreds of different varieties are grown in various parts of the world. The fig was one of the first fruit trees to come under cultivation. Its fruit contains significant amounts of calcium, potassium, phosphorus, and iron.

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Viral infection of the upper and sometimes the lower respiratory tract. Symptoms, which are relatively mild, include sneezing, fatigue, sore throat, and stuffy or runny nose (but not fever); they usually last only a few days. About 200 different strains of virus can produce colds; they are spread by direct or indirect contact. The cold is the most common of all illnesses; the average person gets several every year. Incidence peaks in the fall. Treatment involves rest, adequate fluid intake, and over-the-counter remedies for the symptoms. Antibiotics do not combat the virus but may be given if secondary infections develop.

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Large European beetle (Melolontha melolontha) that damages foliage, flowers, and fruit as an adult and plant roots as a larva. In Britain, the name refers more broadly to any of the beetles in this subfamily (Melolonthinae), which are known in North America as June beetles. Seealso chafer, scarab beetle.

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Hardy, greenish brown fish (Cyprinus carpio, family Cyprinidae) native to Asia but introduced into Europe, North America, and elsewhere. Large-scaled, with two barbels (fleshy, whiskerlike feelers) on each side of its upper jaw, the carp lives alone or in small schools in quiet, weedy, mud-bottomed ponds, lakes, and rivers. An omnivore, it often stirs up sediment while rooting about for food, adversely affecting many plants and animals. Carp grow to an average length of about 14 in. (35 cm); some grow to 40 in. (100 cm) and 49 lbs (22 kg). In captivity they may live more than 40 years.

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later European Community (EC) known as the Common Market

Association of European countries designed to promote European economic unity. It was established by the Treaty of Rome in 1957 to develop the economies of the member states into a single common market and to build a political union of the states of western Europe. The EEC also sought to establish a single commercial policy toward nonmember countries, to coordinate transportation systems, agricultural policies, and general economic policies, to remove measures restricting free competition, and to assure the mobility of labour, capital, and entrepreneurship among member states. The liberalized trade policies it sponsored from the 1950s were highly successful in increasing trade and economic prosperity in western Europe. In 1967 its governing bodies were merged into the European Community. In 1993 the EEC was renamed the European Community (EC); it is now the principal organization within the European Union.

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