from the highest points of the chain. This portion of the range is crossed near its southern termination by a railway from Foligno to Ancona (which at Fabriano has a branch to Macerata and Porto Civitanova, on the Adriatic coast railway), which may perhaps be conveniently regarded as its boundary.[5] By some geographers, indeed, it is treated as a part of the central Apennines.

2. The central Apennines are the most extensive portion of the chain, and stretch as far as the valley of the Sangro (_Sangrus_). To the north are the Monti Sibillini, the highest point of which is the Monte Vettore (8128 ft.). Farther south three parallel chains may be traced, the westernmost of which (the Monti Sabini) culminates to the south in the Monte Viglio (7075 ft.), the central chain in the Monte Terminillo (7260 ft.), and farther south in the Monte Velino (8160 ft.), and the eastern in the Gran Sa.s.so d"Italia (9560 ft.), the highest summit of the Apennines, and the Maiella group (Monte Amaro, 9170 ft.). Between the western and central ranges are the plain of Rieti, the valley of the Salto (_Himella_), and the Lago Fucino; while between the central and eastern ranges are the valleys of Aquila and Sulmona. The chief rivers on the west are the Nera (_Nar_), with its tributaries the Velino (_Velinus_) and Salto, and the Anio, both of which fall into the Tiber.

On the east there is at first a succession of small rivers which flow into the Adriatic, from which the highest points of the chain are some 25 m. distant, such as the Potenza (_Flosis_), Chienti (_Cluentus_), Tenna (_Tinna_), Tronto (_Truentus_), Tordino (_Helvinus_), Vomano (_Voma.n.u.s_), &c. The Pescara (_Aternus_), which receives the Aterno from the north-west and the Gizio from the south-east, is more important; and so is the Sangro.

The central Apennines are crossed by the railway from Rome to Castelammare Adriatico via Avezzano and Sulmona: the railway from Orte to Terni (and thence to Foligno) follows the Nera valley; while from Terni a line ascends to the plain of Rieti, and thence crosses the central chain to Aquila, whence it follows the valley of the Aterno to Sulmona. In ancient times the Via Salaria, Via Caecilia and Via Valeria-Claudia all ran from Rome to the Adriatic coast. The volcanic mountains of the province of Rome are separated from the Apennines by the Tiber valley, and the Monti Lepini, or Volscian mountains, by the valleys of the Sacco and Liri.

3. In the southern Apennines, to the south of the Sangro valley, the three parallel chains are broken up into smaller groups; among them may be named the Matese, the highest point of which is the Monte Miletto (6725 ft.). The chief rivers on the south-west are the Liri or Garigliano (anc. _Liris_) with its tributary the Sacco (_Trerus_), the Volturno (_Volturnus_), Sebeto (_Sabatus_), Sarno (_Sarnus_), on the north the Trigno (_Trinius_), Biferno (_Tifernus_), and Fortore (_Frento_). The promontory of Monte Gargano, on the east, is completely isolated, and so are the volcanic groups near Naples. The district is traversed from north-west to south-east by the railway from Sulmona to Benevento and on to Avellino, and from south-west to north-east by the railways from Caianello via Isernia to Campoba.s.so and Termoli, from Caserta to Benevento and Foggia, and from Nocera and Avellino to Rocchetta S. Antonio, the junction for Foggia, Spinazzola (for Barletta, Bari, and Taranto) and Potenza. Roman roads followed the same lines as the railways: the Via Appia ran from Capua to Benevento, whence the older road went to Venosa and Taranto and so to Brindisi, while the Via Traiana ran nearly to Foggia and thence to Bari.



The valley of the Ofanto (_Aufidus_), which runs into the Adriatic close to Barletta, marks the northern termination of the first range of the Lucanian Apennines (now Basilicata), which runs from east to west, while south of the valleys of the Sele (on the west) and Basiento (on the east)-which form the line followed by the railway from Battipaglia via Potenza to Metaponto--the second range begins to run due north and south as far as the plain of Sibari (_Sybaris_). The highest point is the Monte Pollino (7325 ft.). The chief rivers are the Sele (_Silarus_)--joined by the Negro (_Tanager_) and Calore (_Calor_)--on the west, and the Bradano (_Brada.n.u.s_), Basiento (_Casuentus_), Agri (_Aciris_), Sinni (_Siris_) on the east, which flow into the gulf of Taranto; to the south of the last-named river there are only unimportant streams flowing into the sea east and west, inasmuch as here the width of the peninsula diminishes to some 40 m. The railway running south from Sicignano to Lagonegro, ascending the valley of the Negro, is planned to extend to Cosenza, along the line followed by the ancient Via Popilia, which beyond Cosenza reached the west coast at Terina and thence followed it to Reggio. The Via Herculia, a branch of the Via Traiana, ran from Aequum Tutic.u.m to the ancient Nerulum. At the narrowest point the plain of Sibari, through which the rivers Coscile (_Sybaris_) and Crati (_Crathis_) flow to the sea, occurs on the east coast, extending halfway across the peninsula. Here the limestone Apennines proper cease and the granite mountains of Calabria (anc. _Bruttii_) begin. The first group extends as far as the isthmus formed by the gulfs of S. Eufemia and Squillace; it is known as the Sila, and the highest point reached is 6330 ft. (the Botte Donato). The forests which covered it in ancient times supplied the Greeks and Sicilians with timber for shipbuilding.

The railway from S. Eufemia to Catanzaro and Catanzaro Marina crosses the isthmus, and an ancient road may have run from Squillace to Monteleone. The second group extends to the south end of the Italian peninsula, culminating in the Aspromonte (6420 ft.) to the east of Reggio di Calabria. In both groups the rivers are quite unimportant.

_Character_.--The Apennines are to some extent clothed with forests, though these were probably more extensive in cla.s.sical times (Pliny mentions especially pine, oak and beech woods, _Hist. Nat_. xvi. 177); they have indeed been greatly reduced in comparatively modern times by indiscriminate timber-felling, and though serious attempts at reafforestation have been made by the government, much remains to be done. They also furnish considerable summer pastures, especially in the Abruzzi: Pliny (_Hist. Nat_. xi. 240) praises the cheese of the Apennines. In the forests wolves were frequent, and still are found, the flocks being protected against them by large sheep-dogs; bears, however, which were known in Roman times, have almost entirely disappeared. Nor are the wild goats called _rotae_, spoken of by Varro (_R. R._ II. i.

5), which may have been either chamois or steinbock, to be found.

Brigandage appears to have been prevalent in Roman times in the remoter parts of the Apennines, as it was until recently: an inscription found near the Furlo pa.s.s was set up in A.D. 246 by an _evocatus Augusti_ (a member of a picked corps) on special police duty with a detachment of twenty men from the Ravenna fleet (G. Henzen in _Romische Mitteilungen_, 1887, 14). Snow lies on the highest peaks of the Apennines for almost the whole year. The range produces no minerals, but there are a considerable number of good mineral springs, some of which are thermal (such as Bagni di Lucca, Monte Catini, Monsummano, Porretta, Telese, &c.), while others are cool (such as Nocera, Sangemini, Cinciano, &c.), the water of which is both drunk on the spot and sold as table water elsewhere. (T. As.)

_Geology_.--The Apennines are the continuation of the Alpine chain, but the individual zones of the Alps cannot be traced into the Apennines.

The zone of the Brianconnais (see ALPS) may be followed as far as the Gulf of Genoa, but scarcely beyond, unless it is represented by the Trias and older beds of the Apuan Alps. The inner zone of crystalline and schistose rocks which forms the main chain of the Alps, is absent in the Apennines except towards the southern end. The Apennines, indeed, consist almost entirely of Mesozoic and Tertiary beds, like the outer zones of the Alps. Remnants of a former inner zone of more ancient rocks may be seen in the Apuan Alps, in the islands off the Tuscan coast; in the Catena Metallifera, Cape Circeo and the island of Zannone, as well as in the Calabrian peninsula. These remnants lie at a comparatively low level, and excepting the Apuan Alps and the Calabrian peninsula they do not now form any part of the Apennine chain. But that in Tertiary times there was a high interior zone of crystalline rocks is indicated by the character of the Eocene beds in the southern Apennines. These are formed to a large extent of thick conglomerates which are full of pebbles and boulders of granite and schist. Many of the boulders are of considerable size and they are often still angular. There is now no crystalline region from which they could reach their present position; and this and other considerations have led the followers of E. Suess to conclude that even in Tertiary times a large land ma.s.s consisting of ancient rocks occupied the s.p.a.ce which is now covered by the southern portion of the Tyrrhenian Sea. This old land ma.s.s has been called Tyrrhenis, and probably extended from Sicily into Latium and as far west as Sardinia.

On the Italian border of this land there was raised a mountain chain with an inner crystalline zone and an outer zone of Mesozoic and Tertiary beds. Subsequent faulting has caused the subsidence of the greater part of Tyrrhenis, including nearly the whole of the inner zone of the mountain chain, and has left only the outer zones standing as the present Apennines.

Be this as it may, the Apennines, excepting in Calabria, are formed chiefly of Tria.s.sic, Jura.s.sic, Cretaceous, Eocene and Miocene beds. In the south the deposits, from the Trias to the middle Eocene, consist mainly of limestones, and were laid down, with a few slight interruptions, upon a quietly subsiding sea-floor. In the later part of the Eocene period began the folding which gave rise to the existing chain. The sea grew shallow, the deposits became conglomeratic and shaly, volcanic eruptions began, and the present folds of the Apennines were initiated. The folding and consequent elevation went on until the close of the Miocene period when a considerable subsidence took place and the Pliocene sea overspread the lower portions of the range.

Subsequent elevation, without folding, has raised these Pliocene deposits to a considerable height--in some cases over 3000 ft. and they now lie almost undisturbed upon the older folded beds. This last elevation led to the formation of numerous lakes which are now filled up by Pleistocene deposits. Both volcanic eruptions and movements of elevation and depression continue to the present day on the sh.o.r.es of the Tyrrhenian Sea. In the northern Apennines the elevation of the sea floor appears to have begun at an earlier period, for the Upper Cretaceous of that part of the chain consists largely of sandstones and conglomerates. In Calabria the chain consists chiefly of crystalline and schistose rocks; it is the Mesozoic and Tertiary zone which has here been sunk beneath the sea. Similar rocks are found beneath the Trias farther north, in some of the valleys of Basilicata. Glaciers no longer exist in the Apennines, but Post-Pliocene moraines have been observed in Basilicata.

REFERENCES.--G. de Lorenzo, "Studi di geologia nell" Appennino Meridionale," _Atti d. R. Accad. d. Sci, Fis. e Mat._, Napoli, ser. 2, vol. viii., no. 7 (1896); F. Sacco, "L" Appennino settentrionale,"

_Boll. Soc. geol. Ital._ (1893-1899). (P. La.)

FOOTNOTES:

[1] The ancient Via Aemilia, built in 109 B.C., led over this pa.s.s, but originally turned east to Dertona (mod. _Tortona_).

[2] There are two separate lines from Sampierdarena to Ronco.

[3] This pa.s.s was also traversed by a nameless Roman road.

[4] This river (anc. Aesis) was the boundary of Italy proper in the 3rd and 2nd centuries B.C.

[5] The Monte Conero, to the south of Ancona, was originally an island of the Pliocene sea.

APENRADE, a town of Germany in the Prussian province of Schleswig, beautifully situated on the Apenrade Fjord, an arm of the Little Belt, 38 m. N. of the town of Schleswig. Pop. (1900) 5952. It is connected by a branch line with the main railway of Schleswig, and possesses a good harbour, which affords shelter for a large carrying trade. Fishing, shipbuilding and various small factories provide occupation for the population. The town is a bathing resort, as is Elisenlund close by.

APERTURE (from Lat. _aperire_, to open), an opening. In optics, it is that portion of the diameter of an object-gla.s.s or mirror through which light can pa.s.s free from obstruction. It is equal to the actual diameter of the cylinder of rays admitted by a telescope.

APEX, the Latin word (pl. _apices_) for the top, tip or peak of anything. A diminutive "apiculus" is used in botany.

APHANITE, a name given (from the Gr. [Greek: aphanes], invisible) to certain dark-coloured igneous rocks which are so fine-grained that their component minerals are not detected by the unaided eye. They consist essentially of plagioclase felspar, with hornblende or augite, and may contain also biot.i.te, quartz and a limited amount of orthoclase.

Although a few authorities still recognize the aphanites as a distinct cla.s.s, most systematic petrologists, at the present time, have discarded it, and regard these rocks as merely structural facies of other species.

Those which contain hornblende are uniform, fine-grained diorites, vogesites, &c., while when pyroxene predominates they are ascribed to the dolerites, quartz-dolerites, &c. Hence, any rock which is compact, crystalline and fine grained, is frequently said to be _aphanitic_, without implying exactly to which of the princ.i.p.al rock groups it really belongs.

APHASIA[1] (from Gr. [Greek: a], privative, and [Greek: phasis], speech), a term which means literally inability to speak, and is used to denote various defects in the comprehension and expression of both spoken and written language which result from lesions of the brain.

Aphasic disorders may be cla.s.sed in two groups:--first, receptive or sensory aphasia, which comprises (a) inability to understand spoken language (auditory aphasia), and (b) inability to read (visual aphasia, or _alexia_); second, emissive or motor aphasia, under which category are included (a) inability to speak (motor vocal aphasia, or _aphemia_), and (b) inability to write (motor graphic aphasia, or _agraphia_). It has been shown that each of these defects is produced by destruction of a special region of the cortex of the brain. These regions, which are termed the speech centres, are, in right-handed people, situated in the left cerebral hemisphere; this is the reason why aphasia is so commonly a.s.sociated with paralysis of the right side of the body.

A study of the acquisition of the faculty of speech throws light upon the education of the speech centres, and helps to elucidate their physiological interaction and the phenomena of aphasia. The auditory speech centre is the first to show signs of functional activity, for within a few months of birth the child begins to _understand_ spoken language. Some months later the motor vocal speech centre begins to functionate. The memories of the auditory word images which are stored up in the auditory speech centre play a most important part in the process of learning to speak. The child born deaf grows up mute. The visual speech centre comes into activity when the child is taught to read. Again, when he learns to write and thus begins to educate his graphic centre, he is constantly calling upon his visual speech centre for the visual images of the words he wishes to produce. From these remarks it will be seen that there is a very intimate a.s.sociation between the auditory speech centre and the motor vocal speech centre, also between the visual speech centre and the graphic centre.

_Auditory Aphasia._--The auditory speech centre is situated in the posterior part of the first and second temporo-sphenoidal convolutions on the left side of the brain. Destruction of this centre causes "auditory aphasia." Hearing is unimpaired but spoken language is quite unintelligible. The subject of auditory aphasia may be compared to an individual who is listening to a foreign language of which he does not understand a word. Word deafness, a term often used as synonymous with auditory aphasia, is misleading and should be abandoned. Auditory aphasia commonly interferes with vocal expression, for the majority of people when they speak do so by recalling the auditory memories of words stored up in the auditory speech centre. _Amnesia verbalis_ is employed to designate failure to call up in the memory the images of words which are needed for purposes of vocal expression or silent thought.

_Visual Aphasia or Alexia._--The visual speech centre, which is located in the left angular gyrus, is connected with the two centres for vision which are situated one in either occipital lobe. Destruction of the visual speech centre produces visual aphasia or alexia. Word blindness, sometimes used as the equivalent of visual aphasia, is, like word deafness, a misleading term. The individual is not blind, he sees the words and letters perfectly, but they appear to him as unintelligible cyphers. When the visual speech centre is destroyed, the memories of the visual images of words are obliterated and interference with writing, a consequence of _amnesia verbalis_, results. On the other hand, when the lesion is situated deeply in the occipital lobe, and does not implicate the cortex, but merely cuts off the connexions of the angular gyrus with both visual centres, agraphia is not produced, for the visual word centre and its connexion with the graphic centre are still intact (pure, or sub-cortical word blindness).

_Motor Vocal Aphasia or Aphemia._--The centre for motor vocal speech is situated in the posterior part of the third left frontal convolution and extends on to the foot of the left ascending frontal convolution (Broca"s convolution). Complete destruction of this region produces loss of speech, although it often happens that a few words, such as "yes" and "no," and, it may be, emotional exclamations such as "Oh! dear!" and the like are retained. The utterance of unintelligible sounds is still possible, however, and there is neither defective voice production (_aphonia_) nor paralysis of the mechanism of articulation. The individual can recall the auditory and visual images of the words which he wishes to use, but his memory for the complicated, co-ordinated movements which he acquired in the process of learning to speak, and which are necessary for vocal expression, has been blotted out. In the great majority of cases of motor vocal aphasia there is a.s.sociated agraphia, a circ.u.mstance which is perhaps to be accounted for by the proximity of the graphic centre. When the lesion is situated below the cortex of Broca"s convolution but destroys the fibres which pa.s.s from it towards the internal capsule, agraphia is not produced (sub-cortical or pure motor vocal aphasia). Destruction of the auditory speech centre is, as we have seen, commonly accompanied by more or less interference with vocal speech, a consequence of _amnesia verbalis_.

_Agraphia._--Discussion still rages as to the presence of a special writing centre. Those who favour the separate existence of a graphic centre locate it in the second left frontal convolution. It may be that the want of unanimity as to the graphic centre is to be explained by an anatomical relationship so close between the graphic centre and that for the fine movement of the hand that a lesion in this situation which produces agraphia must at the same time cause a paralysis of the hand.

Destruction of the visual speech centre by obliterating the visual memories of words (_amnesia verbalis_) produces agraphia. Further, several instances are on record in which agraphia has followed destruction of the commissure between the visual speech centre and the graphic centre. As already mentioned, agraphia is very often a.s.sociated with motor vocal aphasia.

A number of aphasic defects are met with in addition to those already mentioned. Thus _paraphasia_ is a condition in which the patient makes use of words other than those he intends. He may mix up his words so that his conversation is quite unintelligible. In the most p.r.o.nounced forms he gabbles away, employing unrecognizable sounds in place of words (_jargon and gibberish aphasia_). _Paragraphia_ is a similar defect which occurs in writing. Both paraphasia and paragraphia may be produced by partial lesions of the sensory speech centres or of the commissures which connect these with the motor centres. _Object blindness_ (syn.

mind-blindness) refers to an inability to recognize an object or its uses by the aid of sight alone. The probable explanation would seem to be that the ordinary centre for vision has been isolated from the other sensory centres with which it is connected. Not uncommonly there is a.s.sociated visual aphasia. _Optic aphasia_ was introduced to designate a somewhat similar state in which, although the uses of an object are recognized, the patient cannot name it at sight, yet, if it is of such a nature that it appeals directly to one of the other senses, he may at once be able to name it. _Tactile aphasia_, is a rare defect in which there exists an inability to recognize an object by touch alone although the qualities which, under normal circ.u.mstances, suffice for its detection can be accurately described. _Amusia_, or loss of the musical faculty, may occur in a.s.sociation with or independent of aphasia. There is reason for believing that special receptive and emissive centres exist for the musical sense exactly a.n.a.logous to those for speech.

The speech centres are all supplied by the left middle cerebral artery.

When this artery is blocked close to its origin by an _embolus_ or _thrombus_, total aphasia results. It may be, however, that only one of the smaller branches of the artery is obstructed, and, according to the region of the brain to which this branch is distributed, one or more of the speech centres may be destroyed. Occlusion of the left posterior cerebral artery causes extensive softening of the occipital lobe and produces pure word blindness. Further, a tumour, abscess, haemorrhage or meningitis may be so situated as to damage or destroy the individual speech centres or their connecting commissures. The amount of recovery to be expected in any given case depends upon the nature, situation and extent of the lesion, and upon the age of the patient. Even after complete destruction of the speech centres, perfect recovery may take place, for the centres in the right hemisphere of the brain are capable of education. This is only possible in young individuals. In the great majority of instances the nature of the lesion is such as to render futile all treatment directed towards its removal. In suitable cases, however, the education of the right side of the brain may be very greatly a.s.sisted by an intelligent application of scientific methods.

BIBLIOGRAPHY.--Broca, _Bulletin de la Societe anatomique_ (1861); Wernicke, _Der Aphasische Symptomen-complex_ (Breslau, 1874); Kussmaul, _Ziemssen"s Cyclopaedia_, vol. xiv. p. 759; Wyllie, _The Disorders of Speech_ (1895); Elder, _Aphasia and the Cerebral Speech Mechanism_ (1897); Collins, _The Faculty of Speech_ (1897); Bastian, _Aphasia and other Speech Defects_ (1898); Byrom Bramwell, "Will-making and Aphasia," _British Medical Journal_ (1897); "The Morison Lectures on Aphasia," _The Lancet_ (1906). See also the works of Charcot, Hughlings Jackson, Dejerine, Lichtheim, Pitres, Gra.s.set, Ross, Broadbent, Mills, Bateman, Mirallie, Exner, Marie and others.

(J. B. T.)

FOOTNOTE:

[1] In 1906 Pierre Marie of Paris expressed views (_La Semaine medicale_, May 23 and October 17, and elsewhere) upon the question of aphasia which have given rise to much animated controversy, since they are in many respects at complete variance with the cla.s.sical conception which has been represented in the present article. Marie holds that Broca"s convolution plays no special role in the function of speech. He admits that a lesion in the region of the lenticular nucleus is followed by inability to speak, but this defect is, in his opinion, to be regarded as an anarthria. He further admits the production of sensory aphasia--the aphasia of Wernicke, as he prefers to call it after its discoverer--by lesions which destroy the angular and supramarginal gyri, and the upper two temporo-sphenoidal convolutions, but he regards the essential foundation of sensory aphasia as a diminution of intelligence. There are, in his opinion, no sensory images of language. Motor aphasia is, he believes, nothing more than a combination of sensory aphasia and anarthria. These conclusions have been vigorously attacked, more especially by Dejerine of Paris (_La Presse medicale_, July 1906 and elsewhere).

APHELION (from Gr. [Greek: apo], from, and [Greek: helios], sun), in astronomy, that point of the orbit of a planet at which it is most distant from the sun. Apogee, Apocentre, Aposaturnium, &c. are terms applied to those points of the orbit of a body moving around a centre of force--as the Earth, Saturn, &c.--at which it is farthest from the central body.

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