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have been founded largely on the observations of Dr Beaumont in the celebrated case of Alexis St Martin, are only valuable within certain limits when applied to the treatment of dyspepsia. It must be borne in mind that idiosyncrasy often plays an important part in digestion, some persons being unable to partake without injury of substances which are generally regarded as wholesome and digestible. Difficulty, too, is often experienced in dealing with dyspeptics from their aversion to, or want of appetite for, those forms of diet which appear most suitable for them. Experience has shown that in this complaint no particular kind of food is absolutely to be relied on, but that in general the best diet is one of a mixed animal and vegetable kind simply but well cooked. The partaking of many dishes, of highly seasoned or salted meats, raw vegetables, newly baked bread, pastry, and confectionery, are all well known common causes of dyspepsia, and should be avoided. When even the simple diet usually taken is found to disagree, it may be necessary to change it temporarily for a still lighter form, such as a milk diet, and that even in very moderate quantity.

General hygienic measures are highly important, since whatever improves the state of the health will have a favourable influence on digestion. Hence regular exercise in the open air, early rising, and the cold bath are to be strongly recommended.

The medicinal remedies for dyspepsia are exceedingly numerous, and a few only of them can be mentioned. Attacks brought on by errors in diet are generally relieved by small doses of rhubarb and bismuth, and by the use of small quantities of light and bland food. In chronic dyspepsia the treatment must depend on the cause of the disorder, so far as that can be ascertained. When the dyspepsia is of the atonic form without much irritability of stomach, bitter tonics such as nux vomica, calumba, gentian, or quassia, along with some of the mineral acids taken before, with, or immediately after a meal will be found highly serviceable; while on the other hand, when there is gastric irritation with acid eructations, sickness, and pain, the medicinal hydrocyanic acid along with bismuth, and antacids taken after food will often afford relief. Pepsine is a remedy of undoubted value in many cases of dyspepsia, and appears to supply the place of that ingredi ent of the gastric juice when it is deficient in amount. It may be given along with a meal, alone, or in conjunction with diluted hydrochloric acid, which also is a remedy of great efficacy in indigestion. Strict attention must ever be paid to the regular action of the bowels, and where laxatives are required an aloetic dinner pill, or, what is often better, one of the mineral bitter waters (such as that of Frederickshall) which are now so commonly used, should be had recourse to.

The employment of alcoholic stimulants to assist digestion is largely resorted to both with and without medical advice. While it seems probable that in certain cases of atonic dyspepsia, particularly in the feeble and aged, the moderate administration of alcohol has the effect of stimulating the secretion of gastric juice, and is an important adjuvant to other remedies, the advantages of its habitual use as an aid to digestion by the young and otherwise healthy is more than questionable, and it will generally be found that among them those are least troubled with indigestion who abstain from it. See PHYSIOLOGY and DIETETICS (3.0.A.)

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DYVEKE, in German often Düveke, and in the Latin chronicles Columbella, the "Little Dove," the name by which the mistress of Christian II. of Denmark is invariably designated. Her father was a certain Sigbrit Villums, who had been obliged for political reasons to leave his native country of Holland. Settling at Bergen; he opened an inn, which soon became known for something more than the hospitality of the host or the excellence of his cheer: his daughter's beauty was bush enough for his weakest wine. Valkendorp, the chancellor, did not think it unbecoming of his priestly character to sound her praise in the ears of the young crown-prince; and accordingly, when he visited Bergen in 1507, the prince made a point of seeing the "Little Dove" for himself. In matters of this sort there is unquestionably a royal road; and so having danced with her at a ball or two, he had little difficulty in getting her to leave the inn for a house of her own at Oslo. She followed him to Copenhagen on his accession in 1513, and both her father and mother obtained unusual influence at court. In 1515 the young king, indeed, was constrained from reasons of state to marry Isabella, the sister of Charles V.; but in spite of the emperor's remonstrance, his relations with Dyveke and her parents underwent no real alteration till her sudden death in 1517. That she had been poisoned was the natural verdict of the popular feeling; and the royal suspicion fell on Torben Oxa, warden of the castle of Copenhagen, who was known to have made love to the girl before she was carried off by the prince; and was it not true that two days before her death he had sent her a present of cherries? It mattered not that the culprit was declared innocent by the royal council: "though his neck were as thick as the neck of a bull it should not save his head," raged the king; and he kept his word. Such is the story, not altogether authenticated, which has furnished a favourite theme to dramatist and novelist, Samsoë the Danish poet, published his well-known tragedy "Dyveke " in the close of the 18th century, and it was translated by Manthey into German in 1798. Münch treated the subject in a semi-historical manner in his Biograph.-histor. Studien; Hermann Marggraff's tragedy of Das Taübchen von Amster dam appeared in 1839, Rickhoff's Duveke in 1842, Hauch's Wilhelm Zabern in 1834, Ida Frick's Sybrecht Willums in 1843, and Mosenthal's Düveke in 1860.

DZUNGARIA, DSONGARIA, or SONGARIA, a former Mongolian kingdom of Central Asia, raised to its highest pitch by Kaldan or Bushtu Khan in the latter half of the 17th century, but completely destroyed by Chinese invasion about 1757-59. It derived its name from the Dsongars, or Songars, who were so called because they formed the left wing (dson, left; gar, hand) of the Mongolian army. Its widest limit included Kashgar, Yarkand Khotan, the whole region of the Thian Shan Mountains, and in short the greater proportion of that part of Central Asia which extends from 35° to 50° N. lat. and from 72° to 97° E. long. The name, however, is more properly applied only to the present Chinese province of Thian-Shanpe-lu and the country watered by the Ili. As a political or geographical term it has practically disappeared from the map; but the range of mountains stretching north-east along the southern frontier of the Land of the Seven Streams-as the district to the south-east of the Balkhash Lake is called-preserves the name of the Dzungarian Range,

588

is the second vowel-symbol and the fifth letter in our

E

original work. Eachard attributed the contempt into which

E the act. Lite original form among the Phoenicians the clergy had fallen to their imperfect education, their

it represented the rough breathing-our h: we have seen that A represented the smooth breathing. As the Greeks had the sound h at a very early period, it might have been expected that this symbol would have been taken by them with its original value. But the want of symbols to denote the vowels was apparently felt to be more imperative; therefore all the Phoenician symbols (corresponding to the Hebrew aleph, he, ayin) were taken to denote the vowelsounds a, e, o respectively. The form of the symbol E has varied little from the earliest Greek times to our own. In old Latin it is sometimes, but rarely, found in the form. The typical sound of E in almost all languages is one of those which we denote generally by a in English, e.g., in the word fate-that is, one of the simple sounds between A (English ah) and I (English ee), which are produced by raising the tongue gradually from its lowest position (at A) to its highest position (at I): in this scale of sounds the lips are not employed. The most clearly distinguished of these sounds are (1) that in men, (2) that in fair, (3) that in fate. It will be observed that these sounds have here different symbols; and if these were consistently employed in English we should not have much reason to complain of our spelling; but e has also the Isound in here and see; ai in wait has the same sound as a in fate; and a has many sounds. Other languages employ diacritical marks to distinguish these sounds; thus in Italian we have è and é, called " open " and "close" e respectively; these correspond very nearly to (2) and (3) mentioned above. It is probable that the same distinction of sound was given in Latin by employing ae to express the open e at least open e is commonly found in Italian words which were written in Latin with ue, or with e short. It is possible that in Greece a similar distinction of close open e was expressed in early times by the symbols (epsilon) and (eta); but in Attica, at least after 403 B.C., the distinction seems to have been rather quantitative than qualitative. For the history of eta see article H. It is clear that in a perfect alphabet we ought to have at least three distinct symbols between A and I: we ought not to be compelled to distinguish the simple sounds by diphthongs or other modifications. Indeed yet more symbols would be desirable, for there are other sounds in this scale, which, however, are not easily distinguished from the above except by a practised ear.

η

It is probable that ee in English of the 16th and 17th centuries had the sound still heard in Scotland in words like ell, i.e., the simple e in our men pronounced long: this is not unlike the open e, but the back of the tongue is lower. But ee had acquired its present I sound in the last century.

EACHARD, JOHN (1636-1697), an English divine, was born in Suffolk in 1636, and was educated at Catherine Hall, Cambridge, of which he became master in 1675 in succession to Lightfoot. He was created a doctor of divinity in 1676 by royal mandate, and was twice (in 1679 and 1695) vice-chancellor of the university. He died on the 7th July 1697. In 1670 he had published anonymously a humorous satire entitled The Ground and Occasions of the Contempt of the Clergy enquired into in a letter to R. I., which excited much attention and provoked several replies, one of them being from John Owen. These were met by Some Observations, etc., in a second letter to R. L. (1671), written in the same bantering tone as the

insufficient incomes, and the want of a true vocation. He gave amusing illustrations of the absurdity and poverty of the current pulpit oratory of his day, some of them being taken from the sermons of his own father. He attacked the philosophy of Hobbes in his Mr Hobbs's State of Nature considered; in a dialogue between Philautus and Timothy (1672), and in his Some Opinions of Mr Hobbs considered in a second dialogue (1673). These were written in their author's chosen vein of light satire, and Dryden praised them as highly effective within their own range. It is noteworthy that Eachard's own sermons were not superior to those he satirized. Swift alludes to him as a signal instance of a successful humorist who entirely failed as a serious writer. A collected edition of his works in three volumes, with a notice of his life, was published in 1774.

EADIE, JOHN (1810-1876), theologian and biblical critic, was born at Alva, in Stirlingshire, on the 9th May 1810. Having manifested unusual ability at school, he was sent to the university of Glasgow, where he passed through the usual curriculum in arts. Immediately afterwards he commenced to study for the ministry at the Divinity Hall of the Secession Church, a dissenting body which, on its union a few years later with the Relief Church, adopted the denomination United Presbyterian. In 1835 he was ordained to the pastoral charge of the Cambridge Street Secession church in Glasgow. Here he speedily attained a position of great eminence and usefulness, and for many years before the close of his life he was generally regarded as the leading representative of his denomination in the city which has always been its stronghold. Though he had little claim to be called eloquent, and his style was often slovenly, he had many of the other qualities that secure the most useful and enduring kind of popularity. preacher he was distinguished by invariable good sense, frequent flashes of happy illustration, masculine piety, deep spiritual earnestness, breadth of sympathy both intellectual and emotional, and-most specifically of all-by the power he had in his expository discourses of conveying the best results of biblical criticism in an intelligible form to a general audience. Behind the carelessness and apparent indifference of his manner, it was not difficult to detect the quick sensibility and tender feeling which were eminently characteristic of the man. Though more than once invited to an important charge elsewhere, Dr Eadie refused to leave Glasgow, in which he found a sphere more exactly suited to his pastoral gifts than he could expect in any other place. In 1863 he removed with a portion of his congregation to a new and beautiful church at Lansdowne Crescent, where his influence continued unabated until his death.

As a

From his student days Eadie bore a reputation for extensive, if not profound and accurate, scholarship, which he justified and increased during the earlier years of his ministry to such an extent that in 1843 the church to which he belonged appointed him professor of biblical literature and hermeneutics in its Divinity Hall. He held this appointment along with his ministerial charge till the close of his life, and discharged its duties with an efficiency that was universally acknowledged. While his scholarship was not minute or thorough, he was surpassed by few biblical commentators of his day in range of learning, and by still fewer in the soundness of judgment with which his learning was applied. As a critic he was acute and painstaking;

In the

as an interpreter he was eminently fair-minded. professor's chair, as in the pulpit, his strength lay in the tact with which he selected the soundest results of biblical criticism, whether his own or that of others, and presented them in a clear and connected form, with a constant view to their practical bearing. If this last fact gave a nonacademic aspect to some portions of his lectures, it rendered them not less interesting and probably not less useful to his auditors. Eadies merits as a scholar were early acknowledged by the usual honorary university distinctions. He received the degree of LL.D. from Glasgow in 1844, and that of D.D. from St Andrews in 1850. Busily engaged as he was in two distinct offices, either of which might well of itself have employed all his energies, Eadie nevertheless found time for an amount of work in a third sphere, of which the same thing might be said. His labours as an author would have been more than creditable to one who had no other occupation. Most of his works were connected with biblical criticism and interpretation, some of them being designed for popular use and others being more strictly scientific. To the former class belong the Biblical Cyclopædia, his edition of Cruden's Concordance, his Early Oriental History, and his discourses on The Divine Love and on Paul the Preacher; to the latter belong his commentaries on the Greek text of St Paul's epistles to the Ephesians, Colossians, Philippians, and Galatians, published at intervals in four volumes, which take a high rank among exegetical works. His Life of Dr Kitto obtained a deserved popularity. His last work, the History of the English Bible (2 vols. 1876), will probably be the most enduring memorial of his ability as an author. Though not unimpeachable in point of arrangement and style, it contains a fuller and more accurate account of the subject than is to be found anywhere else, and almost every page bears marks of the life-long interest and loving research of the author. His almost unrivalled knowledge of the various English versions, as well as his ability as a critic and interpreter of the original, led to his being selected as one of the company for the revision of the authorized version of the New Testament, and in this capacity it is understood that he rendered excellent service. Dr Eadie died at Glasgow on the 3d June 1876.

EADMER, or EDMER (in Latin Eadmerus, and by mistake Edimerus and Edinerus), an English ecclesiastic and historian of the Norman period, probably, as his name suggests, of English as opposed to Norman parentage. At an early age he was sent to the Benedictine monastery at Canterbury; and there he became acquainted with Anselm, at the time of the latter's first visit to England as abbot of Bec. The intimacy was renewed when Anselm was raised to the episcopal see; and thenceforward Eadmer was not so much the archbishop's disciple and follower as his friend and director, and that at last not only by Anselm's private recognition, but by the formal appointment of Pope Urban II. So complete, indeed, was the obedience shown by the great scholastic philosopher and head of the English Church to his self-elected tutor, that-according to William of Malmesbury, De gestis pontificum Anglorum, lib. i.-he is said to have waited for his express permission before he rose from his bed, or even turned from one side to the other. After Anselm's death Eadmer accompanied Radulph, the new archbishop, to Rome in 1119; and on their return in 1120 he was nominated to the see of St Andrews in Scotland. Owing, however, to the refusal of the Scotch to recognize the claims put forward by Eadmer and his patron in support of the episcopal authority of the see of Canterbury, he was never formally inducted into the office. He was at Canterbury in 1121, and he spent the latter part of his life as prior of the monastery there. His death is variously assigned to the year 1123 and 1137.

Eadmer has left a large number of works, of which a list is given in Wharton's Anglia Sacra, part ii. Most important are his the death of Radulph in 1122, and his Vita Anselmi, which Historia Novorum, in six books treating of his own times down to ranks as one of the chief authorities in regard to the primate. The former was first published by Selden in 1623, the latter at Antwerp in 1551; and both have since been several times reprinted. Of less mark are his lives of Odo, Bregwin, and Dunstan, and of Oswald and Wilfrid of York, and his treatises-formerly ascribed to Anselm-De quatuor virtutibus quæ fuerunt in beata Maria virgine, and De Similitudinibus S. Anselmi. Nearly all his works are to be found in an early MS. in the library of Corpus Christi been reprinted as an appendix to Anselm's Opera by Gerberon, fol. College, Cambridge (C.C.C.C., No 371), and most of them have 1675, and by the Benedictine monks of St Maure, fol. Paris, 1721. A number of his letters are preserved in MSS. Cotton., Otho, A. xii. Charma, Saint Anselm, 1853, pp. 186, 187; Burton, History of Scotland, vol. I. pp. See especially Wright, Biographia Brit. Lit, Anglo-Norman Period, 1846;

422-424.

EAGLE (French Aigle, from the Latin Aquila), the name generally given to the larger Diurnal Birds-of-prey which are not Vultures; but the limits of the subfamily Aquiline have been very variously assigned by different writers on systematic ornithology, and, as before observed (BJZZARD, vol. iv. p. 603), there are Eagles smaller than certain Buzzards. By some authorities the Lammergeier of the Alps, and other high mountains of Europe, North Africa, and Asia, is accounted an Eagle, but by others the genus Gypaetus is placed with the Vulturida, as its common English name (Bearded Vulture) shows. There are also other forms, such as the South-American Harpyia and its allies, which though generally called Eagles have been ranked as Buzzards. In the absence of any truly scientific definition of the family Aquiline it is best to leave these and many other more or less questionable members of the group-such as the genera Spizaetus, Circaetus, Spilornis, Helotarsus, and so forth-and, so far as space will allow, to treat here of those whose position cannot be gainsaid.

True Eagles inhabit all the Regions of the world, and some seven or eight species at least are found in Europe, of which two are resident in the British Islands. In England and in the Lowlands of Scotland Eagles only exist as stragglers; but in the Hebrides and some parts of the Highlands a good many may yet be found, and their numbers appear to have rather increased of late years than diminished; for the foresters and shepherds, finding that a high price can be got for their eggs, take care to protect the owners of the eyries, which are nearly all well known, and to keep up the stock by allowing them at times to rear their young. There are also now not a few occupiers of Scottish forests who interfere so far as they can to protect the king of birds. But hardly twenty years ago trapping, poisoning, and other destructive devices were resorted to without stint, and there was then every probability that before long not an Eagle would be left to add the wild majesty of its appearance to the associations of the mountain or the lake. In Ireland the extirpation of Eagles seems to have been carried on almost unaffected by the prudent considerations which in the northern kingdom have operated so favourably for the race, and except in the wildest parts of Donegal, Mayo, and Kerry, Eagles in the sister-island are said to be almost birds of the past. Of the two British species the Erne (Icel. Ern) or Sea

1 The late Lord Breadalbane was perhaps the first large landowner On his who set the example that has been since followed by others. unrivalled forest of Black Mount, Eagles-elsewhere persecuted to the death-were by him ordered to be unmolested so long as they were not numerous enough to cause considerable depredations on the farmers' flocks. He thought, and all who have an eye for the harmonies of nature will agree with him, that the spectacle of a soaring Eagle was a fitting adjunct to the grandeur of his Argyllshire mountainscenery, and a good equivalent for the occasional loss of a lamb, or the slight deduction from the rent paid by his tenantry in consequence. How faithfully his wishes were carried out by his head-forester, Mr Peter Robertson, the present writer has abundant means of knowing,

[merged small][merged small][graphic][graphic]

FIG. 1.-Sea-Eagle.

yearly do, and appear in England. The adults (fig. 1) are distinguished by their prevalent greyish-brown colour, their pale head, yellow beak, and white tail-characters, however, wanting in the immature, which do not assume the perfect plumage for some three or four years. The eyry is commonly placed in a high cliff or on an island in a lake sometimes on the ground, at others in a tree-and consists of a vast mass of sticks, in the midst of which is formed a hollow lined with Luzula sylvatica (as first observed by the late Mr John Wolley) or some similar grass, and here are laid the two or three white eggs. In former days the SeaEagle seems to have bred in several parts of England-as the Lake district, and possibly even in the Isle of Wight and on Dartmoor. This species inhabits all the northern part of the Old World from Iceland to Kamchatka, and breeds in Europe so far to the southward as Albania. the New World, however, it is only found in Greenland, being elsewhere replaced by the White-headed or Bald Eagle, H. leucocephalus, a bird of similar habits, and the chosen emblem of the United States of America. In the far east of Asia occurs a still larger and finer Sea-Eagle, H. pelagicus, remarkable for its white thighs and upper wing Coverts. South-eastern Europe and India furnish a much smaller species, H. leucoryphus, which has its representative, H. leucogaster, in the Malay Archipelago and Australia, and, as allies in South Africa and Madagascar, H. vocifer and H. vociferoides respectively. All these Eagles may be distinguished by their scaly tarsi, while the group next to be treated of have the tarsi feathered to the toes.

In

The Golden or Mountain-Eagle, Aquila chrysaetus, is the second British species. This also formerly inhabited England, and a nest, found in 1668 in the Peak of Derby

FIG. 2.-Golden Eagle.

neighbourhood of water is not requisite. The eggs, from two to four in number, vary from a pure white to a mottled, and often highly-coloured, surface, on which appear dif ferent shades of red and purple. The adult bird (fig. 2) is of a rich, dark brown, with the elongated feathers of the neck, especially on the nape, light tawny, in which imagination sees a "golden" hue, and the tail marbled with brown and ashy-grey. In the young the tail is white at the base, and the neck has scarcely any tawny tint. The Golden Eagle does not occur in Iceland, but occupies suitable situations over the rest of the Palearctic Region and a considerable portion of the Nearctic-though the American bird has been, by some, considered a distinct species. Domesticated, it has many times been trained to take prey for its master in Europe, and to this species is thought to belong an Eagle habitually used by the Kirgiz Tartars, who call it Bergut or Bearcoot, for the capture of antelopes, foxes, and wolves. It is carried hooded on horseback or on a perch between two men, and released when the quarry is in sight. Such a bird, when well trained, is valued, says Pallas, at the price of two camels. It is quite possible, however, that more than one kind of Eagle is thus used, and the services of A. hebiaca (which is the Imperial Eagle of some writers) and of A. mogilnik

1 As already stated, the site chosen varies greatly. Occasionally placed in a niche in what passes for a perpendicular cliff to which access could only be gained by a skilful cragsman with a rope, the writer has known a nest to within ten or fifteen yards of which he rode on a pony. Two beautiful views of as many Golden Eagle's nests drawn on the spot by Mr Wolf, are given in the Ootheca Welleyana, and a fine series of eggs is also figured in the same work.

Which species may have been the traditional emblem of Roman power, and the Ales Jovis, is very uncertain.

both of which are found in Central Asia, as well as in South-eastern Europe-may also be employed.

Of the other more or less nearly allied species or races want of room forbids the consideration, but there is a smaller form on which a few words may be said. This has usually gone under the name of A. navia, but is now thought by the best authorities to include three local races, or, in the eyes of some, species. They inhabit Europe, North Africa, and Western Asia to India, and two examples of one of them-A. clanga, the form which is somewhat plentiful in North-eastern Germany-have occurred in Cornwall. The smallest true Eagle is A. pennata, which inhabits Southern Europe, Africa, and India. Differing from other Eagles, of their genus by its wedgeshaped tail, though otherwise greatly resembling them, is the A. audax of Australia. Lastly may be noticed here a small group of Eagles, characterized by their long legs, forming the genus Nisaetus, of which one species, N. fasciatus, is found in Europe. The Osprey (Pandion), though placed by many among the Aquilina, certainly does not belong to that subfamily. (A. N.)

2. Transmission in Middle Ear.-The middle ear is a small cavity, the walls of which are rigid with the exception of the portions consisting of the membrana tympani, and the membrane of the round window and of the apparatus filling the oval window. This cavity communicates with the pharynx by the Eustachian tube, which forms a kind of air-tube between the pharynx and the tympanum for the purpose of regulating pressure on the membrana tympani. It is generally supposed that during rest the tube is open, and that it is closed during the act of deglutition. As this action is frequently taking place, not only when food or drink is introduced, but when saliva is swallowed, it is evident that the pressure of the air in the tympanum will be kept in a state of equilibrium with that of the external air on the outer surface of the membrana tympani, and that thus the membrana tympani will be rendered independent of variations of atmospheric pressure such as may occur within certain limits, as when we descend in a diving bell or ascend in a balloon. By a forcible expiration, the oral and nasal cavities being closed, air may be driven into the tympanum, while a forcible inspiration (Valsalva's experi ment) will draw air from that cavity. In the first case, the membrana tympani will bulge outwards, in the second case inwards, and in both, from excessive stretching of the membrane, there will be partial deafness, especially for one of the most common causes of deafness.

EAR. The simplest form of the organ of hearing is a small sac containing fluid, with the auditory nerve expanded upon it. Sonorous vibrations are communicated to this sac either directly through the hard parts of the head, or at the same time by a membrane exposed to the surround-sounds of high pitch. Permanent occlusion of the tube is ing medium. Such is the form of ear found in many of the Crustacea and in the Cephalopoda. In the Vertebrata,. there is a progressive development and increasing complexity from the fishes up to Mammalia. For details as to the structure of the ear in the different subdivisions of the Vertebrata, reference is made to the articles treating of these, such as AMPHIBIA, BIRDS, &c.; and the structure of the human ear will be found fully described in the article ANATOMY, Vol. i. p. 891. It is the object of this article to describe the phenomena of auditory sensation from the physiological point of view.

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I-1. Transmission in External Ear. The external ear consists of the pinna, or auricle, and the external auditory meatus, or canal, at the bottom of which we find the membrana tympani, or drum head. In many animals the auricle is trumpet-shaped, and, being freely movable by muscles, serves to collect sonorous waves coming from various directions. The auricle of the human ear presents many irregularities of surface. If these irregularities are abolished by filling them up with a soft material such as wax or oil, leaving the entrance to the canal free, experiment shows that the intensity of sounds is weakened, and that there is more difficulty in judging of their direction. When waves of sound strike the auricle, they are partly reflected outwards, while the remainder, impinging at various angles, undergo a number of reflections so as to be directed into the auditory canal. Vibrations are transmitted along the auditory canal, partly by the air it contains and partly by its walls, to the membrana tympani. The absence of the auricle, as the result of accident or injury, has not caused diminution of hearing. In the auditory canal, waves of sound are reflected from side to side until they reach the membrana tympani. From the obliquity in position and peculiar curvature of this membrane, most of the waves must strike it nearly perpendicularly, and in the most advantageous direction.

The membrana tympani is capable of being set into vibration by a sound of any pitch included in the range of perceptible sounds. It responds exactly as to number of vibrations (pitch), intensity of vibrations (intensity), and complexity of vibration (quality or timbre). Consequently we can hear a sound of any given pitch, of a certain intensity, and in its own specific timbre or quality. Generally speaking, very high tones are heard more easily than low tones of the same intensity. As the membrana tympani is not only fixed by its margin to a ring or tube of bone, but is also adherent to the handle of the malleus, which follows its movements, its vibrations meet with considerable resistance. This diminishes the intensity of its vibrations, and prevents also the continued vibration of the membrane after an external vibration has ceased, so that a sound is not heard much longer than it lasts. The tension of the membrane may be affected (1) by differences of pressure on the two surfaces of the membrana tympani, as may occur during forcible expiration or inspiration, or in a pathological condition, and (2) by muscular action, due to contraction of the tensor tympani muscle. This small muscle arises from the apex of the petrous temporal and the cartilage of the Eustachian tube, enters the tympanum at its anterior wall, and is inserted into the malleus near its root. The handle of the malleus is inserted between the layers of the membrana tympani, and, as the malleus and incus prove round an axis passing through the neck of the malleus from before backwards, the action of the muscle is to pull the membrana tympani inwards towards the tympanic cavity in the form of a cone, the meridians of which, according to Helmholtz, are not straight but curved, with convexity outwards. When the muscle contracts, the handle of the malleus is drawn still farther inwards, and thus a greater tension of the tympanic membrane is produced. On relaxation of the muscle, the membrane returns to its position of equilibrium by its own elasticity and by the elasticity of the chain of bones. This power of varying the tension of the membrane is a kind of accommodating mechanism for receiving and transmitting sounds of different pitch. With different degrees of tension, it will respond more readily to sounds of different pitch. Thus, when the membrane is tense, it will readily respond to high sounds, while relaxation will be the condition most

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