Part 11

The effects of high pressure are seen in divers, caisson workers, miners. The effects of low pressure are seen in balloonists, airmen. The effect of sudden return to normal from high pressure is seen in cases of caisson disease (q.v.). The effects of low pressure were first applied to the human body in 1835 by V.T. Junot. He contrived a hollow copper ball, 4 yards in diameter, capable of containing a man, and by pumping out air gradually, produced the effects of low pressure. This principle was then applied by him locally by cupping-glasses similar in shape to the upper part of a wineglass. There are two types of cupping:

(a) In _wet cupping_ an incision is made in the skin of the part to be treated. The air inside the glass is exhausted by introducing a lighted match, then the open end of the glass is immediately applied to the surface of the skin.

(b) In _dry cupping_ the treatment is similarly carried out, but no incision is made.

The low pressure (partial vacuum) draws blood to the part. Cupping is used in congestion of internal organs, e.g. lungs, kidneys.

The artificial application of air to lungs at varying pressure is carried out by inspiring rarefied air or compressed air and expiring into rarefied air or into compressed air. Only inspiring compressed air, or expiring into rarefied air, can be practically applied. There are many kinds of apparatus for this. The best is the compressed-air bath (seen at Brompton Hospital, London), consisting of three parts--the engine, receiver, and air-chamber.

The patient is placed in this air-chamber, where he remains for two hours, during which time the pressure is usually raised from half again to double normal. For the first half-hour the pressure is gradually raised, and is maintained at the same abnormal height for one hour; for the last half-hour it is reduced again gradually to normal. The patient first experiences an unpleasant sensation in the throat. This is relieved by swallowing or by drinking water; then pain in the ear-drums; the voice becomes shriller. These are early signs of the effects of high pressure, and are seen to a more marked degree in cases where a man has descended suddenly into a mine, caisson, &c. Compressed air-baths are used in cases of asthma, bronchitis, emphysema, anaemia.

Respiratory gymnastics are of value for defective breathing due to badly formed chests or injury and disease of the lungs. There are various forms of artificial breathing exercises and many ways of using artificial aids, e.g. breathing into bottles connected together by tubes and partly filled with water. The water is forced from one bottle to another by the respiratory effort of the patient.

AERSCHOT, town in Belgium, province of Brabant, on the Demer, a tributary of the Dyle. It was occupied by the Germans in Aug., 1914. Pop. 7800.

AESCHINES (es'ki-n[=e]z), a celebrated Athenian orator, the rival and opponent of Demosthenes, was born in 389 B.C. and died in 314. He headed the Macedonian party in Greece, or those in favour of an alliance with Philip, while Demosthenes took the opposite side. Having failed in 330 B.C. in a prosecution against Ctesiphon for proposing to bestow a crown of gold upon Demosthenes for his services to the State (whence the oration of Demosthenes 'On the Crown') he left Athens, and subsequently established a school of eloquence at Rhodes. Three of his orations are extant. Aeschines should not be confounded with his namesake, the Athenian philosopher and intimate friend of Socrates.

AESCHYLUS (es'ki-lus), the first in time of the three great tragic poets of Greece, born at Eleusis, in Attica, 525 B.C., died in Sicily 456. Before he gained distinction as a dramatist he had fought at the battle of Marathon (490), as he afterwards did at Artemisium, Salamis, and Plataea. He first gained the prize for tragedy in 484 B.C. _The Persians_, the earliest of his extant pieces, formed part of a trilogy which gained the prize in 472 B.C. In 468 B.C. he was defeated by Sophocles, and then is said to have gone to the Court of Hiero, King of Syracuse. Altogether he is reputed to have composed ninety plays and gained thirteen triumphs. Only seven of his tragedies are extant: _The Persians_, _Seven against Thebes_, _Suppliants_, _Prometheus_, _Agamemnon_, _Choephori_, and _Eumenides_, the last three forming a trilogy on the story of Orestes, represented in 458 B.C. Aeschylus may be called the creator of Greek tragedy, both from the splendour of his dramatic writings and from the scenic improvements and accessories he introduced. Till his time only one actor had appeared on the stage at a time, and by bringing on a second he was really the founder of dramatic dialogue. His style was grand, daring, and full of energy, and his choruses, though difficult, are among the noblest pieces of poetry in the world. His plays have little or no plot, and his characters are drawn by a few powerful strokes. There are English poetical translations of his plays by Blackie, Plumptre, Swanwick, Campbell, Robert Browning, and Elizabeth Barrett Browning.--BIBLIOGRAPHY: Bishop Copleston, _Aeschylus_, in English Classics for Modern Readers Series (Blackwood & Son); Miss J. Case, Translation of _Prometheus Vinctus_ (Dent).

AESCULA'PIUS (Gr. _Askl[=e]pios_), the god of medicine among the Greeks and afterwards adopted by the Romans, usually said to have been a son of Apollo and the nymph Coronis. He was worshipped in particular at Epidaurus, in the Peloponnesus, where a temple with a grove was dedicated to him. The sick who visited his temple had to spend one or more nights in the sanctuary, after which the remedies to be used were revealed in a dream. Those who were cured offered a sacrifice to Aesculapius, commonly a cock. He is often represented with a large beard, holding a knotty staff, round which is entwined a serpent, the serpent being specially his symbol. The staff and serpent have been adopted as a badge by the Royal Army Medical Corps. Sometimes Aesculapius is represented under the image of a serpent only.--BIBLIOGRAPHY: L. Dyer, _The Gods of Greece_; W. H. D. Rouse, _Greek Votive Offerings_.

AES'CULUS, the genus of plants to which belongs the horse-chestnut.

AESIR, in Scandinavian mythology, the eleven chief gods, besides Odin. They are: Thor, Balder, Ty or Tyr, Bragi, Heimdal, Hod, Vidar, Vali, Ull, Forseti, and Loki or Lopt. See _Scandinavian Mythology_.

AE'SOP, the Greek fabulist, is said to have been a contemporary of Croesus and Solon, and thus probably lived about the middle of the sixth century (620-550) B.C. But so little is known of his life that his existence has been called in question. He is said to have been originally a slave, and to have received his freedom from a Samian master, Iadmon. He then visited the court of Croesus, and is also said to have visited Pisistratus at Athens. Finally he was sent by Croesus to Delphi to distribute a sum of money to each of the citizens. For some reason he refused to distribute the money, whereupon the Delphians, enraged, threw him from a precipice and killed him. No works of Aesop are extant, and it is doubtful whether he wrote any. Bentley inclined to the supposition that his fables were delivered orally and perpetuated by repetition. Such fables are spoken of both by Aristophanes and Plato. Phaedrus turned into Latin verse the Aesopian fables current in his day, with additions of his own. In modern times several collections claiming to be Aesop's fables have been published. Cf. J. Jacobs, _The Fables of Aesop_.

AESTHET'ICS (Gr. _aisth[=e]tikos_, pertaining to perception), the philosophy of the beautiful; the name given to the branch of philosophy or of science which is concerned with that class of emotions, or with those attributes, real or apparent, of objects generally comprehended under the term _beauty_, and other related expressions. The term aesthetics first received this application from Baumgarten (1714-62), a German philosopher, who was the first modern writer to deal systematically with the subject, though the beautiful had received attention at the hands of philosophers from early times. Socrates, according to Xenophon, regarded the beautiful as coincident with the good, and both as resolvable into the useful. Plato, in accordance with his idealistic theory, held the existence of an absolute beauty, which is the ground of beauty in all things. He also asserted the intimate union of the good, the beautiful, and the true. Aristotle treated of the subject in much more detail than Plato, but chiefly from the scientific or critical point of view. In his treatises on _Poetics_ and _Rhetoric_ he lays down a theory of art, and establishes principles of beauty. His philosophical views were in many respects opposed to those of Plato. He does not admit an absolute conception of the beautiful; but he distinguishes beauty from the good, the useful, the fit, and the necessary. He resolves beauty into certain elements, as order, symmetry, definiteness. A distinction of beauty, according to him, is the absence of lust or desire in the pleasure it excites. Beauty has no utilitarian or ethical object; the aim of art is merely to give immediate pleasure; its essence is imitation. Plotinus agrees with Plato, and disagrees with Aristotle, in holding that beauty may subsist in single and simple objects, and consequently in restoring the absolute conception of beauty. He differs from Plato and Aristotle in raising art above nature. Baumgarten's treatment of aesthetics is essentially Platonic. He made the division of philosophy into logic, ethics, and aesthetics; the first dealing with knowledge, the second with action (will and desire), the third with beauty. He limits aesthetics to the conceptions derived from the senses, and makes them consist in confused or obscured conceptions, in contradistinction to logical knowledge, which consists in clear conceptions. Kant, in his _Critique of the Power of Judgment_, defines beauty in reference to his four categories, quantity, quality, relation, and modality. In accordance with the subjective character of his system he denies an absolute conception of beauty, but his detailed treatment of the subject is inconsistent with the denial. Thus he attributes a beauty to single colours and tones, not on any plea of complexity, but on the ground of purity. He holds also that the highest meaning of beauty is to symbolize moral good, and arbitrarily attaches moral characters to the seven primary colours. The value of art is mediate, and the beauty of art is inferior to that of nature. The treatment of beauty in the systems of Schelling and Hegel could with difficulty be made comprehensible without a detailed reference to the principles of these remarkable speculations. English writers on beauty are numerous, but they rarely ascend to the heights of German speculation. Shaftesbury adopted the notion that beauty is perceived by a special internal sense; in which he was followed by Hutcheson, who held that beauty existed only in the perceiving mind, and not in the object. Numerous English writers, among whom the principal are Alison and Jeffrey, have supported the theory that the source of beauty is to be found in association--a theory analogous to that which places morality in sympathy. The ability of its supporters gave this view a temporary popularity, but its baselessness has been effectively exposed by successive critics. Dugald Stewart attempted to show that there is no common quality in the beautiful beyond that of producing a certain refined pleasure; and Bain agrees with this criticism, but endeavours to restrict the beautiful within a group of emotions chiefly excited by association or combination of simpler elementary feelings. Herbert Spencer has a theory of beauty which is subservient to the theory of evolution. He makes beauty consist in the play of the higher powers of perception and emotion, defined as an activity not directly subservient to any processes conducive to life, but being gratifications sought for themselves alone. He classifies aesthetic pleasures according to the complexity of the emotions excited, or the number of powers duly exercised; and he attributes the depth and apparent vagueness of musical emotions to associations with vocal tones built up during vast ages. Among numerous writers who have made valuable contributions to the scientific discussion of aesthetics may be mentioned Winckelmann, Lessing, Richter, the Schlegels, Gervinus, Helmholtz, Ruskin, Home, Hogarth, Burke, Taine, and others.--BIBLIOGRAPHY: Herbert Spencer, _Principles of Psychology_; Grant Allen, _Physiological Aesthetics_; A. Bain, _Emotions and Will_; B. Bosanquet, _History of Aesthetics_; W. Knight, _Philosophy of the Beautiful_.

AESTIVA'TION, a botanical term applied to the arrangement of the parts of a flower in the flower-bud previous to the opening of the bud.--The term is also applied to the summer sleep of animals. See _Dormant State_.

AETH'ELING. See _Atheling_.

AE'THER. See _Ether_.

AETHIO'PIA. See _Ethiopia_.

AE'THRIOSCOPE (Gr. _aithrios_, clear, cloudless), an instrument (devised by Sir John Leslie) for measuring radiation towards a clear sky, consisting of a metallic cup with a highly-polished interior of paraboloid shape, in the focus of which is placed one bulb of a differential thermometer, the other being outside. The inside bulb at once begins to radiate heat when exposed to a clear sky, and the extent to which this takes place is shown by the scale of the thermometer. The aethrioscope also indicates the presence of invisible aqueous vapour in the atmosphere, radiation being less than when the air is dry.

AETHU'SA, a genus of umbelliferous plants. See _Fool's Parsley_.

AETIOLOGY (Gr. _aitia_, cause, and _logos_, discourse), the theory of the physical causes of any class of phenomena, or the science of causation. It is, however, mainly used in medicine, and deals with the causes and origin of disease.

AE'TIUS, a general of the western Roman Empire, born A.D. 396; murdered 454. As commander in the reign of Valentinian III he defended the empire against the Huns, Visigoths, Franks, Burgundians, &c., completely defeating the Huns under Attila in a great battle at Chalons in 451. For twenty years he was at the head of public affairs, and in the end was murdered by Valentinian, who was jealous of his power.

AET'NA. See _Etna_.

AETO'LIA, a western division of northern Greece, separated on the west by the Achelous from Acarnania and washed by the Corinthian Gulf on the south. The inhabitants are little heard of in Greek history till the Peloponnesian war, at which time they were notorious among the Greeks for the rudeness of their manners. Aetolia, in conjunction with Acarnania, now forms a nomarchy of the kingdom of Greece.

AFANASIEV, Alexander Nicolaievitsh, Russian folklorist, born in 1826. Besides numerous articles and essays he wrote several monumental works: _The Ancient Slav's Poetic View of Nature_ (3 vols., 1866-9), _Russian Tales and Fables for Children_ (3 vols., 1870), &c. He died in 1871.

AFFIDA'VIT, a written statement of facts upon oath or affirmation. Affidavits are generally made use of when evidence is to be laid before a judge or a court, while evidence brought before a jury is delivered orally. The person making the affidavit signs his name at the bottom of it, and swears that the statements contained in it are true. The affidavit may be sworn to in open court, or before a magistrate or other duly qualified person; it may be made abroad before a qualified British state official.

AFFIN'ITY, in chemistry, the force by which unlike kinds of matter combine so intimately that the properties of the constituents are lost, and a compound with new properties is produced. Of the force itself we know little or nothing. It is not the same under all conditions, being very much modified by circumstances, especially temperature. The usual effect of increase of temperature is to diminish affinity and ultimately to cause the separation of a compound into its constituents; and there is probably for every compound a temperature above which it could not exist, but would be broken up. Where two elements combine to form a compound, heat is almost always evolved, and the amount evolved serves as a measure of the affinity. In order that chemical affinity may come into play it is necessary that the substances should be in contact, and usually one of them at least is a fluid or a gas. The results produced by chemical combination are endlessly varied. Colour, taste, and smell are changed, destroyed, or created; harmless constituents produce strong poisons, strong poisons produce harmless compounds.

AFFINITY, in law, is that degree of connection which subsists between one of two married persons and the blood relations of the other. It is no real kindred (consanguinity). A person cannot, by legal succession, receive an inheritance from a relation by affinity; neither does it extend to the nearest relations of husband and wife so as to create a mutual relation between them. The degrees of affinity are computed in the same way as those of consanguinity or blood. All legal impediments arising from affinity cease upon the death of the husband or wife, excepting those which relate to the marriage of the survivor.

AFFIRMA'TION, a solemn declaration by Quakers, Moravians, Dunkers, and others, who object to taking an oath, in confirmation of their testimony in courts of law, or of their statements on other occasions on which the sanction of an oath is required of other persons. In England the form for Quakers is, 'I do solemnly, sincerely, and truly declare and affirm'. Affirmation is generally allowed to be substituted for an oath in all cases where a person refuses to take an oath from conscientious motives, if the judge is satisfied that the motives are conscientious. False affirmation is subjected to the same penalties as perjury.

AFFREIGHTMENT means the contract of carriage of goods by sea, by which the shipowner undertakes to carry goods in his ship for hire or _freight_. Unless otherwise stipulated, the merchant or freighter is only bound to pay the freight upon delivery of the goods at the agreed destination. If the voyage is abandoned, the merchant may claim his goods without any payment. The merchant must load and discharge his cargo within the _lay-days_ or stipulated time, if any; otherwise within a reasonable time. Failure entails liability in damages--known as _demurrage_--for undue detention of the ship. The merchant will also be liable in damages--known as _dead-freight_--if he fails to furnish the full cargo promised. The shipowner has a lien on the goods for their own freight and charges, but not for a general balance. Nor has he any lien for dead-freight or demurrage. All such liens may be validly stipulated for in the contract. They are purely possessory as contrasted with the so-called maritime liens for seamen's and shipmasters' wages, which are valid without possession. There is no lien for _advance freight_, which in Scotland is repayable if the cargo is lost at sea or delivery otherwise prevented, but not so in England. In Scotland, accordingly, the burden of insuring advance freight falls upon the shipowner, in England upon the merchant.

The main obligations upon the shipowner are to provide a seaworthy vessel, carry without undue delay, and deliver the goods in the same condition as they were shipped. Unless otherwise agreed, he is liable for damage or loss through negligence, and if he be a common carrier, as he frequently is, even the absence of negligence may not save him. There is nothing in British law, however, to prevent him from contracting out of all responsibility for the safety of goods committed to his care, and he generally does so, either by inserting what is known as an 'exception clause' in the document evidencing the contract, viz. the Bill of Lading, or by giving public notice that he only accepts goods upon that footing. In this respect the position of shipowners is more favourable than that of railway companies and other land carriers, whose freedom of contract is curtailed by statute.--BIBLIOGRAPHY: T. G. Carver, _Carriage by Sea_; Sir T. E. Scrutton, _Contract of Affreightment_.

AFFRIQUE ([.a]f-r[=e]k), St., a town of southern France, department of Aveyron.

AFGHANISTAN ([.a]f-g[:a]n'i-st[:a]n), that is, the land of the Afghans, a country in Asia, bounded on the east by the N. W. Frontier Province, &c., on the south by Baluchistan, on the west by the Persian province of Khorasan, and on the north by Bukhara and Russian Turkestan. The eastern and southern boundaries were settled in 1893, whilst the boundary towards Persia was demarcated between March, 1903, and May, 1905. The area may be set down at about 250,000 sq. miles. The population is estimated at 6,000,000. Afghanistan consists chiefly of lofty, bare, uninhabited tablelands, sandy barren plains, ranges of snow-covered mountains, offsets of the Hindu Kush or the Himalaya, and deep ravines and valleys. Many of the last are well watered and very fertile, but about four-fifths of the whole surface is rocky, mountainous, and unproductive. The surface on the north-east is covered with lofty ranges belonging to the Hindu Kush, whose heights are often 18,000 and sometimes reach perhaps 25,000 feet. The whole north-eastern portion of the country has a general elevation of over 6000 feet; but towards the south-west, in which direction the principal mountain chains of the interior run, the general elevation declines to not more than 1600 feet. In the interior the mountains sometimes reach the height of 15,000 feet. Great part of the frontier towards India consists of the Suleiman range, 12,000 feet high. There are numerous practicable avenues of communication between Afghanistan and India, among the most extensively used being the famous Khyber Pass, by which the River Kabul enters the Punjab; the Gomul Pass, also leading to the Punjab; and the Bolan Pass on the south, through which the route passes to Sind. Of the rivers the largest is the Helmund, which flows in a south-westerly direction more than 400 miles, till it enters the Hamoon or Seistan swamp. It receives the Arghandab, a considerable stream. Next in importance are the Kabul in the north-east, which drains to the Indus, and the Hari Rud in the north-west, which, like other Afghan streams, loses itself in the sand. The climate is extremely cold in the higher, and intensely hot in the lower regions, yet on the whole it is salubrious. The most common trees are the pine, oak, birch, and walnut. In the valleys fruits, in the greatest variety and abundance, grow wild. The principal crops are wheat (forming the staple food of the people), barley, rice, and maize. Other crops are tobacco, sugar-cane, and cotton. The chief domestic animals are the dromedary, the horse, ass, and mule, the ox, sheep with large fine fleeces and enormous fat tails, and goats; of wild animals there are the tiger, bears, leopards, wolves, jackal, hyena, foxes, &c. The chief towns are Kabul (the capital), Kandahar, Ghuzni, and Herat. The inhabitants belong to different races, but the Afghans proper form the great mass of the people. They are allied in blood to the Persians, and are divided into a number of tribes, among which the Duranis and Ghiljis are the most important. The Afghans, claiming descent from King Saul, are called by their own ancient chroniclers Beni-Israel. They are bold, hardy, and warlike, fond of freedom and resolute in maintaining it, but of a restless, turbulent temper, and much given to plunder. Tribal dissensions are constantly in existence, and seldom or never do all the Afghans pay allegiance to the nominal ruler of their country. Their language (Pushtu) is distinct from the Persian, though it contains a great number of Persian words, and is written, like the Persian, with the Arabic characters. In religion they are Mahommedans of the Sunnite sect.