EXCHEQUER AND AUDIT DEPARTMENT, a department of the English Civil Service charged with the functions of auditing the accounts of all other departments.

EXCHEQUER BILLS, bills of credit issued by authority of Parliament as a means of raising money for temporary purposes. They are of various sums--100 or any multiple--and bear interest at a rate fixed for every half-year according to the rate ruling in the money-market at the time.

These bills pa.s.s from hand to hand as money, and form part of the public unfunded debt of Great Britain. _Exchequer bonds_ are similar, but they run for a definite number of years (six at most) at a fixed rate of interest.

EXCISE', an inland duty or impost laid on commodities produced and consumed within a country, and also on licences to manufacture and deal in certain commodities. Excise duties were introduced into England by the Long Parliament in 1643, being then laid on the makers and vendors of ale, beer, cider, and perry. Being found to be a convenient and productive source of revenue, they continued to gain ground, and in 1919 yielded 59,663,000. In Britain the excise includes duties on spirits and beer, licences on dogs, guns, carriages, servants, plate, railways, game, &c. In 1917 an excise duty was laid on entertainments, matches, and table waters. Spirits and beer yield over 44,000,000.

EXCI'TO-MOTOR ACTION, the action of nerves distributed to muscular organs, the stimulation of which leads to movement. Thus, irritation of a nerve supplying a muscle will lead to contraction of the muscle by excito-motor action, and irritation of certain nerves distributed to blood-vessels will lead to contraction of the vessel by acting on its muscular coat.

EXCLUSION, BILL OF, a bill introduced into the British Parliament during the reign of Charles II for the purpose of excluding the Duke of York (afterwards James II), he being a Roman Catholic, from the throne.

EXCOMMUNICATION, the exclusion of a Christian from the communion and spiritual privileges of the Church. Excommunication was a recognized penalty among the Jews (_John_, ix, 22), and was practised early by the Christian Church. A distinction gradually arose between a lesser and a greater excommunication, the former being a suspension from Church privileges, the latter a formal expulsion excluding from all communion with the faithful. In the Middle Ages the Popes often excommunicated whole cities and kingdoms. In such a case all religious services ceased, and the grave inconveniences thus caused made excommunication a formidable weapon in the hands of the Pope, till with frequent abuse it lost its force.

Besides excommunication an extreme degree of denunciation called _anathema_, and cutting the offender off from all the hopes and consolations of the Christian faith, is used in the Roman Catholic Church.

Both Luther and Calvin were in favour of the right of excommunication by the ministers of the Church. In the Church of England both the less and the greater excommunications are recognized.--Cf. E. Taunton, _The Law of the Church_.

EXCRE'TION, in physiology, the separation and carrying off of waste matter from some organ of an animal body, a function performed by the lungs, kidneys, and the skin, besides the action of the intestinal ca.n.a.l.

[Ill.u.s.tration: Excubitorium, St. Alban's Abbey]

EXCUBITO'RIUM, in mediaeval churches, a gallery where public watch was kept at night on the eve of some festival, and from which the great shrines could be seen.

EXE, a river of England, which rises in Exmoor, in the county of Somerset, and after a southerly course of about 50 miles falls into the English Channel at Exmouth.

EXECUTION, in law, is a judicial writ grounded on a judgment of the court by which the writ is issued, and is granted for the purpose of carrying the judgment into effect, by having it executed. Execution is granted by a court only upon the judgments given by the same court, not upon those p.r.o.nounced by another. See _Elegit_; _Fieri facias_.

EXECUTIONER, the official who carries into effect a sentence of death, or inflicts capital punishment in pursuance of a legal warrant. In England the duty of executing the extreme sentence of the law devolves upon the sheriff, and in Scotland on the civic magistracy, but in practice the duty is performed by another in presence of these functionaries. In the reign of James I Gregory Brandon was the executioner of London, and hence the name Gregory has often been employed to designate executioners. In France the executioner is styled Monsieur de Paris.

EXEC'UTIVE, that branch of the government of a country by which the laws are carried into effect or the enforcement of them superintended. The term is used in distinction from the _legislative_ and the _judicial_ departments, and includes the supreme magistrate, whether emperor, king, president, or governor, his cabinet or ministers, and a host of minor officials.

EXEC'UTOR, in law, is one appointed by a man's last will to carry its provisions into execution after the testator's death. The testator may, by the English law, appoint any person of sound mind and discretion, though otherwise under some legal disabilities as to contracting and transacting business in general, such as a married woman, or a minor. The duties of executors and of administrators are, in general, the same, the difference of the two depending mostly on the mode of appointment, the executor being nominated by the testator, the administrator being appointed by the Judge of Probate. In Scotland an executor appointed by will is styled executor _nominate_, and by authority of the court executor _dative_.

EXEQUA'TUR (Lat., 'Let him accomplish'), a written recognition of a consul or commercial agent issued by the Government to which he is accredited, and authorizing him to exercise his powers.

EX'ETER, a city, river-port, parliamentary county, and munic.i.p.al borough of England, county town of Devon, on the left bank of the Exe, 10 miles north-west of its outlet in the English Channel. It is pleasantly situated on the summit and slopes of an acclivity rising from the river, and has handsome squares, terraces, and streets. The chief architectural feature is the cathedral (founded in 1112), a long, low building with fine west front, unique in having two towers forming its transepts, and only these two. The city has remains of the old castle and old walls, Guildhall, Albert Memorial College, training college, and St. Michael's Church. There are iron-foundries, works for agricultural implements and paper, and 'Honiton'

lace is made. By a ca.n.a.l vessels of 300 tons can reach the city. The largest vessels remain at Exmouth. Exeter is a place of remote antiquity, having been a British settlement long prior to the invasion of the Romans, by whom it was called _Isca d.a.m.noniorum_. It was taken by William the Conqueror in 1068. It long returned two members to Parliament, but lost one of them in 1885. Pop. 59,608.

EXETER COLLEGE, Oxford, a college, originally called Stapledon Hall, founded in 1314 by Walter de Stapledon, Bishop of Exeter, who made a foundation for a rector and twelve fellows. In 1404 Edmund Stafford, Bishop of Exeter, added two fellowships and obtained leave to give the college its present name.

EXETER HALL, a large building on the north side of the Strand, London, opened in 1831, and capable of containing over 3000 persons. In it the 'May Meetings' of the several religious societies were held. It was sold in 1907 by the Young Men's Christian a.s.sociation to a firm of caterers, who demolished it in 1908. The Strand Palace Hotel now stands on its site.

EXFOLIATION is the scaling off of dead tissues; thus there may be exfoliation of the skin, of bone, or of other parts from their living surroundings.

EXHIBITION, a fixed sum given for a term of years from the funds of a school, college, or university, generally upon the result of a compet.i.tive examination. An exhibition, no matter what its pecuniary value, is less of a distinction than a scholarship. At Cambridge an exhibitioner has no standing in his college different from that of the ordinary 'pensioner', while a scholar is on the Foundation of his college.

EXHIBITIONS. The earliest recorded 'exhibition', in the modern acceptation of the word, is that in which, for one hundred and eighty days, Ahasuerus "shewed the riches of his glorious kingdom" at Shushan (_Esther_, i, 2-4).

The first European exhibition was held at Venice in 1268; while the great fairs of Leipzig and Nijni-Novgorod partook of the same nature. But the real forerunner of the modern exhibition was that held in London by the Society of Arts in 1756, when carpets, china, and similar artistic objects were displayed. This was followed in 1761 by an exhibition of agricultural machinery. In 1797 France held a display of _objets d'art_ at St. Cloud; there was another two years later at the Louvre; while a third in 1802 is memorable for the first issue of an official catalogue, and for the presence of Montgolfier the aeronaut, and Jacquard the inventor of the loom that bears his name, among exhibitors. Besides the exhibition of Irish industries, held at Dublin (1829), and the Birmingham exhibition of metal-work (1849), numerous displays were held in both Europe and America before the first International or 'Great' Exhibition of 1851. This memorable display was under the active patronage of Prince Albert, and for its accommodation the Crystal Palace was erected in Hyde Park. Its success gave the exhibition movement an impetus which produced examples at New York and Dublin (1853), both of which proved financial failures; at Munich and Melbourne (1854); Paris (1855); and at South Kensington, where was held the second International Exhibition (1862). Five years later, after Constantinople, Oporto, and Agra had, among other places, held displays, came the great Paris Exhibition, planned on a colossal scale; though the main building in the Champ de Mars was stigmatized as 'a gasometer' by Napoleon III. Vienna had a magnificent but financially disastrous exhibition in 1873, and in 1876 Philadelphia celebrated the centenary of the Independence of the United States by a display. In 1878 Paris held another exhibition, for which the Trocadero was built. A series held at South Kensington (1871-4) had only a moderate success, but great popularity was attained by the 'Fisheries', 'Health', 'Inventions', and Colonial Exhibitions held in the years 1883-6. Edinburgh was the scene of a forestry display in 1884, and at the same time New Orleans opened an exhibition which continued till the following year. The Paris Exhibition of 1889 was notable for the 'side-shows', which included the Eiffel Tower; while the financial result of that held in 1900, which covered 550 acres of ground and admitted thirty-nine million people, was far from satisfactory.

Meanwhile Chicago had in 1893 celebrated the four hundredth anniversary of Columbus's discovery of America by a huge 'World's Fair'. The present century opened inauspiciously with the a.s.sa.s.sination of President McKinley at the Pan-American Exhibition at Buffalo (1901); Glasgow had a thoroughly successful exhibition the same year; St. Louis was the scene of another in 1904; while London organized the Franco-British Exhibition in 1908. This last owed much to the late Imre Kiralfy, who had directed many previous displays, and was the designer of the 'White City' at Shepherd's Bush, where in 1914 was held the Anglo-American Exposition. After the conclusion of the European War various plans for new exhibitions were put forward, such as the British Empire Exhibition, which is to be held in London in 1923, and which is intended to foster imperial interests.

EX'ILE, a punishment by which a person is compelled to leave the city, province, or the country where he has previously resided. It is a punishment for State criminals.

EXMOOR', a wild and hilly district of England, in the extreme south-west of Somersetshire, extending also into Devonshire, formerly a forest.

EX'MOUTH, a town of England, in Devonshire, 10 miles S.S.E. of Exeter, at the mouth of the Exe. It is picturesquely situated, and is one of the best-known sea-bathing places on the Devonshire coast. The chief industries are lace-making and the fisheries. Pop. 13,614.

EXMOUTH, Edward Pellew, Viscount, a British naval officer, born at Dover in 1757, died 23rd Jan., 1833. He went to sea at the age of thirteen, served as midshipman in the _Blonde_ frigate during the American War, and greatly distinguished himself at Lake Champlain. In 1782 he was made a post-captain for a brilliant action in the _Pelican_, and on the outbreak of the war in 1793 was appointed to the command of the frigate _La Nymphe_. From this time till the peace in 1802 he was employed on active service. In 1804, on the resumption of hostilities, he was sent to take the chief command on the East India station, in the _Culloden_, of seventy-four guns; and here he remained till 1809, when he had attained the rank of vice-admiral. His next appointment was the command of the fleet blockading the Scheldt. In 1814 he was made Baron Exmouth with a pension of 2000 per annum. In 1816 he was sent with a fleet to punish the Dey of Algiers for outrages committed, and to force him to give up his Christian captives and abolish Christian slavery. Along with some Dutch war vessels he bombarded the city for eight hours, and inflicted such damage that the Dey agreed to every demand. Three thousand Christian slaves were thus restored to liberty. Lord Exmouth was made a viscount and received honours from several of the European sovereigns, and the freedom of the City of London. In 1821 he retired into private life.

EXOASCINEae, a family of parasitic ascomycetous Fungi, distinguished by the absence of any definite fruit-body, the asci being produced in a layer on the surface of the host. The best known are _Exoascus Pruni_, the cause of the mal-formed fruits called 'bladder-plums' or 'pocket-plums', and _E.

turgidus_, which produces the abnormal tufts of branches on silver birch known as 'witches' brooms'.

EXOBASIDIINEae, a family of parasitic basidiomycetous Fungi, resembling the Exoascineae in most respects, but producing basidia in place of asci, a remarkable instance of parallel evolution. The commonest British species is _Exobasidium Vaccinii,_ which is frequent on cowberry (_Vaccinium Vitis-Idaea_) in Scotland. _E. vexans_ is the cause of a serious disease of the tea-plant called 'blister-blight', which is very destructive to the a.s.sam plantations.

EX'ODUS (Gr. _exodos_, a going out), the name given in the _Septuagint_ to the second book of the _Pentateuch_, because it describes the departure of the Israelites from Egypt. The contents of the book are partly historical, describing the departure of the Israelites from Egypt, and partly legislative, describing the promulgation of the Sinaitic law. One of the difficulties connected with this book is that, according to Scriptural chronology, the residence of the Israelites in Egypt was only 215 years, and it seems incredible that in this time "the threescore and ten souls"

who accompanied Jacob to Egypt could have become the two and a half millions who left with Moses.

EXOGAMY (Gr. _exo_, outside, and _gamos_, marriage), a term applied to the custom of allowing marriages only between members who do not belong to the same group. The study of exogamy is practically a branch of ethnology. The opposite of exogamy is endogamy, or prohibition of marriage outside the tribe. Exogamy, which among other causes may be ascribed to a desire of forming useful alliances with hostile tribes, is practised among Australian aborigines, Mongols, and American Indians, and the custom is widely distributed in various forms in all stages of civilization.--BIBLIOGRAPHY: Sir J. G. Frazer, _Totemism and Exogamy_; E. A. Westermarck, _The History of Human Marriage_.

EXOGENOUS PLANTS (_eks-oj'e-nus_), or EXOGENS, old names for Dicotyledons (q.v.).

EXOGENOUS STRUCTURES, in botany, are those which arise from superficial tissues of the parent organ, as stem-branches and leaves. Opposed to endogenous structures.

EX'ORCISM (Gr. _exorkizein_, to expel with an oath), the casting out of evil spirits by certain forms of words or ceremonies. An opinion prevailed in the ancient Church that certain persons, those particularly who were afflicted with certain diseases, especially madness and epilepsy, were possessed by evil spirits; this was called _demoniac possession._ Over such persons forms of conjuration were p.r.o.nounced, and this act was called _exorcism_. There were even certain men who made this a regular profession, and were called _exorcists_. Exorcism still forms a part of the beliefs of some Churches. In the Roman Catholic Church exorcist is one of the inferior orders of the clergy.--Cf. Sir J. G. Frazer, _The Golden Bough_.

EXOSTO'SIS, in medicine, an excrescence or growth from one of the bony structures of the body. It is generally found at the end of long bones near the joints, and in connection with the skull.

EXOTHERMIC COMPOUNDS are compounds which evolve heat during their formation; these are usually stable compounds, as they must be supplied with a corresponding amount of heat for their decomposition.

EXOT'IC, belonging to foreign countries; a term used especially of plants.

Exotic plants are such as belong to a soil and climate entirely different from the place where they are raised. They are nearly always greenhouse or hothouse plants.

EXPANSION, in physics, the increase of the dimensions of a body caused by a change of temperature. In general, bodies expand with rise of temperature, solids expanding least and gases most. This change in the dimensions of solids with temperature is expansion in length, area, and volume. These changes are referred to a unit called the coefficient of expansion, or expansion of unit length, area, or volume for 1 rise. For example, the coefficient of linear expansion of iron is .000011; that is, a yard, say, of iron rod becomes longer by this fraction of a yard for each degree centigrade that its temperature is raised. The coefficient of volume expansion of a solid is three times its linear coefficient. Crystals have different rates of expansion along the three crystalline axes. Fused silica or quartz expands so slightly that it may be plunged when red-hot into water without being cracked. Invar, a nickel-steel alloy, which also has an extremely small coefficient of expansion, is used in making clock pendulums, which are unaffected by change of temperature. The observed expansion of liquids is affected by the expansion of the vessel containing them, and the apparent expansion of a liquid is thus always less than its real expansion. The expansion of water with rise of temperature is irregular; water contracts from 0 to 4C., and thereafter expands at an increasing rate until the boiling-point is reached. The expansion of mercury and other liquids is employed in thermometry. Gases when kept at constant pressure expand by about 1/273rd part of their volume at 0C. for each degree rise.

EXPECTATION, in the doctrine of chances, the value of any prospect of prize or property depending upon the happening of some uncertain event. A sum of money in _expectation_ upon a certain event has a determinate value before that event happens. If the chances of receiving or not receiving a hundred pounds, when an event arrives, are equal, then, before the arrival of the event the expectation is worth half the money.--_Expectation of life_, the number of years which a man or woman of any age may be expected to live. To calculate this with any reasonable degree of probability, it is necessary to have particulars of a large number of individuals. The earliest observations were based upon the records of the registers of certain towns.

Out of a number of people alive at one date the numbers still living at the end of successive years were found, and an estimate of the probable duration of life was made. With increased facilities for collecting statistics of a larger number of lives, this estimate has since been modified. It is necessarily influenced by the progress of civilization, improved methods of sanitation, increased knowledge of the best methods of treating diseases, and other causes, but the collected statistics are now so numerous that the actuaries of life a.s.surance offices have been able to prepare tables of mortality from which the cost of life premiums and the price of annuities are calculated.

EXPEC'TORANTS are drugs used to increase and liquefy the secretion in the lungs and air-pa.s.sages. The most effective are ipecacuanha, squills, apomorphine, ammonium carbonate, and pota.s.sium iodide. Some of these are usually present in the many cough mixtures so widely used.

EXPER'IMENT, an operation designed to discover some unknown truth, principle, or effect, or to establish it when discovered. It differs from observation in the fact that the phenomena observed are, to a greater or less extent, controlled by human agency. Experiment distinguishes the modern method of investigating nature, and to it we owe the rapid strides made in chemistry and physics.

EXPERT' (Lat. _experiri_, to test), a person eminently skilled in any particular branch or profession; specifically, a scientific or professional witness who gives evidence on matters connected with his profession, as an a.n.a.lytical chemist or a person skilled in handwriting.

EXPLOITS', RIVER OF, a river which traverses nearly the whole of Newfoundland from S.W. to N.E., and falls into the Bay of Exploits. It is about 150 miles long, and is navigable for steamers for 12 miles.

EXPLO'SION, a sudden violent outburst accompanied by a loud noise, and giving rise to an impulsive wave which spreads outwards from the place of explosion. Generally applied to the very rapid combustion of explosive substances which, under the influence of heat or shock, are resolved with extreme rapidity into gaseous form. Substances are termed low explosives or high explosives according as they are set off by combustion or detonation.

EXPLOSIVE MECHANISM, in botany, (1) in flowers, an arrangement for the transference of pollen to an insect-visitor by a sudden movement of floral organs. (2) In fruits, an arrangement for the forcible expulsion of seeds from a fruit brought about in various ways (see _Sling-fruits_). The spores of Ferns, ascospores, and some conidia are also liberated explosively.

EXPLOSIVES. An explosive is a substance or mixture of substances which, by the action of a blow or of heat, can be converted very easily and suddenly into a more stable substance or substances, usually gaseous, with the simultaneous liberation of a large amount of heat. Explosives are divided into cla.s.ses according to the uses to which they are put, but the line of demarcation is not always very clear. The industrial and blasting powders may be either low or high explosives. A 'low' explosive explodes by the application of heat, and burns more or less uniformly and slowly, and projects neighbouring objects to a distance. A 'high' explosive explodes under a blow, and the whole of the substance is instantly transformed, and instantly exerts its maximum pressure, creating a violent disturbance in a limited area without necessarily projecting substances to any great distance. Service explosives, for naval and military purposes, are divided into propellants and high explosives. Sporting powders are specially modified propellant powders. Examples of these cla.s.ses of explosives, with notes on their composition, are given below.

_Low Explosives._--The best examples of the low explosive are gunpowder and similar mixtures. The const.i.tuents of the 'gunpowder' explosives are generally not explosive alone, but only when mixed. A 'gunpowder' mixture contains carbon or carbonaceous matter like wood-meal, hydrocarbons, starches, and sugars, &c., which burn owing to the presence of highly oxygenated substances like peroxides, chlorates and perchlorates, nitrates, permanganates, chromates and dichromates, all of which convey the necessary oxygen. In addition, there usually is present some very easily ignited substance like sulphur or sulphides, or phosphorus or phosphides, &c. As compared with other explosives, gunpowder or black-powder has certain advantages. It is cheap, easily ignited, insensitive to shock, and stable at moderately high temperature; it burns regularly, and its residue is non-corrosive. But it is weak in power, and produces much smoke. It is excellent for armour-piercing sh.e.l.l and for rings of time-fuses. Gunpowder made in different countries varies in composition, but for rifle, cannon, and sporting powders it, usually contains 74 to 75 parts of saltpetre, 9 to 14 parts of sulphur, 12 to 16 parts of charcoal. For blasting powders less saltpetre and more charcoal is used. Charcoal is made by the carbonization of wood. In England dogwood, alder, and willow woods are used; in Germany alder and willow are used; in France black alder and also white alder, poplar, aspen, birch, and hazel; in Switzerland hazel wood; in Spain oleander, yew, willow, hemp stems, and vine; in Italy hemp stems. The wood is generally carbonized in iron retorts. The product is allowed to cool out of contact with air, else it may inflame. Wood burnt for ordnance powders gives a yield of 20 to 30 per cent charcoal; that for small-arms gives a yield of 40 per cent. The charcoal contains from 68 to 85 per cent carbon, from 2.8 to 3.7 per cent hydrogen, from 12 to 27 per cent oxygen, and may have up to 5 per cent ash. The saltpetre is found naturally in Chile, India, and in other countries, and is refined by crystallization from water. It is a colourless, crystalline solid. Sulphur, a pale-yellow solid, melting-point 113 C., boiling-point 4445 C., is found in nature, and is refined to a purity of 995 per cent and over. It has a low ignition temperature of 261 C., and makes the powder burn more readily. Under the pressure of the press and the incorporating mill it flows and cements the minute particles of charcoal and saltpetre together. The three ingredients are ground, mixed, sieved, incorporated or mixed in drums or mills, broken down, and then pressed, corned or granulated, and glazed. Cannon powders receive an addition of graphite to reduce the rate of burning. The powder is then dried in a stove, finished in a reel to get rid of the last traces of dust, and blended. In the United States powder for blasting contains sodium nitrate instead of pota.s.sium nitrate. The powder is cheaper and stronger, but is hygroscopic. Sprengsaltpetre is largely used in Sta.s.sfurt salt-mines, where a mild explosive is required, and consists of 75 parts by weight of sodium nitrate, 10 parts by weight of sulphur, and 15 parts by weight of brown coal. It is cheap, and does not produce poisonous fumes.

Bobbinite is largely used in coal-mines. It is black powder with ammonium and copper sulphates, possibly also starch and paraffin wax. When gunpowder explodes, the product consists of 43 per cent gases, 56 per cent solids, and the rest water. The composition of other industrial and blasting powders is given in the sequel.