Slike strani



gambia and the Niger, less the Senegal Pro- dering the coast the rivers during floods overtectorate, which was restored to Senegal. At flow their banks, inundating the plains, and the same time the military territories were become connected with one another by means broken up and became a part of the colony, of canals. On the lower Senegal, so far as the The first military territory was incorporated inundation reaches, vegetation is very luxuriant. in Upper Senegal-Niger, and is administered by Rice, maize and other grains, with bananas, a colonel under the authority of the military manioc and yams, are cultivated equally on the governor; the second territory was handed over hills and plains. The orange, citron and other to the civil administration and the third is fruits introduced by the Portuguese are now still an autonomous unit. Upper Senegal-Niger extensively cultivated on the hills. Wild aniis entirely under civil administration, with the mals comprise the elephant, hippopotamus, same judicial and educational systems as the monkey, antelope, gazelle, lion, panther, leopother colonies comprised in the government- ard, hyena, jackal, crocodile, etc. The cligeneral. The budget of the colony for 1916 mate is intensely hot and unhealthful for Euroamounted to $1,788,641; the local budget for peans. The inhabitants are of many races, the 1914 was $1,918,981. The most important and principal being the Yolofs, Foolahs and Manpopulous towns are Bobo-Dioulasso (8,736 in- dingoes. These negro tribes inhabit for the habitants), Bamako, the capital (6,553), Sikesso most part Middle Senegambia, between the (7,544), Segou (6,550), Kayes (5,900). All the Senegal and the Gambia. Upper Senegambia, principal towns have urban schools. There is to the north of the Senegal, is largely inhabited à professional school at Kayes and a school by Moors, who carry on an extensive trade in for sons of chiefs. There is a Mussulman gum, etc., with the Europeans. The total popusuperior school at Timbuktu (5,100 inhabitants), lation is estimated at 12,000,000. which has 67 pupils. The natives cultivate

SENEY, sē'nĩ, George Ingraham, Ameriground nuts, maize, millet, cotton and rice;

can banker: b. Astoria, Long Island, N. Y., 12 rubber and kariti are also produced. The

May 1826; d. New York, 7 April 1893. He principal native industries are pottery, jewelry,

was educated at the Wesleyan University and brick and leather-making and weaving. Cot

at the University of the City of New York tons, foodstuffs and metal work form the chief

where he was graduated in 1847. He engaged items of import, while cattle, ground nuts,

in the banking business and in 1877–84 was hides, wool and rubber are exported. In 1912

president of the Metropolitan Bank, New York. there were 4,050 miles of telegraph line and 74 He lost heavily at the time of the bank's failmiles of telephone line. The Senegal-Niger

ure in 1884, but later succeeded in partially Railway extends from Kayes to Koulikoro, a re-establishing himself financially. Before 1884 distance of 349 miles. Small steamboats ply be

his benefactions amounted to about $2,000,000. tween Koulikoro and Timbuktu. In 1914

He gave $500,000 to establish the Seney Hosthe imports into Upper Senegal were valued pital in Brooklyn and $500,000 to both the at $1,079,426, and the exports amounted only Wesleyan University and the Methodist Orphan to $462,164. The Niger (territory) is farther

Asylum in Brooklyn. He aiso gave $250,000 to inland than Upper Senegal, therefore, more Emory College and the Wesleyan Female Colremote from the seaports through which all

lege, Macon, Ga., and liberal sums to other West African trade must pass; in consequence public institutions. He sold his famous collecthe over-seas trade is inconsiderable. The value

tion of paintings at auction in 1885, receiving of the imports into the Niger in 1914 amounted $406,910 for them. From a later collection he to $193,117, the principal articles, in addition

gave 20 valuable paintings to the Metropolitan to government purchases, being cotton goods

Museum of Art, New York. and tobacco; the exports reached $117,656 in

SENIJEXTEE. See SALISHAN INDIANS. the same year and consisted mainly of cattle, hides, ostrich feathers, native salt and tanned SENILE DISEASES. See OLD AGE AND sheep and goat skins. Consult Lenfant, Le Its DISEASES. Niger) (Paris 1903); id., La grande route du

SENILITY. To obtain a clear conception Chad' (ib. 1904).

of senility we must consider old age as conSENEGAMBIA, sěn-ě-găm'bi-ą, West Af- sisting of two periods, the presenile and the rica, so named from the Senegal and Gambia senile. Physiologically these periods exist and rivers (qq.v.), an extensive region comprising

are divided by a critical period called the senile the countries between lat. 10° and 17° N.; long.

climacteric which occurs about the 70th year. 4o and 17° 30' W.; bounded on the north by the This period corresponds to puberty during the Sahara, south by Guinea and west by the At- period of development and the menopause and lantic. The area is estimated at from 400,000 The male climacteric during the period of ma10 700,000 square miles, and is almost wholly turity. The senile climacteric, like the male under French influence, with the exception of climacteric, usually causes so little distress that Bissagos Island and some coast territory at the it passes unnoticed. Occasionally those around mouth of the Rio Grande River, belonging to the aged person notice marked changes in menPortugal, and the British Gambia colony at tality, more profound physical changes, greater the mouth of the Gambia. The name Senegam debility, while some prominent manifestations bia is not used by the French, who call their of senility will appear less pronounced. In colony and protectorate Senegal (q.v.). The some cases the climacteric changes are very western portion of the country is a low, flat evident and the person passes rapidly from and, to a great extent, swampy plain. East of a condition of brighť middle-aged mental and this the country is mountainous, and the val- physical activity into a state of senile decrepileys run north and south. The principal rivers tude. are the Senegal, the Gambia, the Jeba or Rio During the senile climacteric the organs and Grande and the Nuñez. In the level tract bor- tissues which have degenerated slowly now SENIOR- SENLAC, BATTLE OF


break down rapidly and the degenerative processes which have gone on rapidly before become less active. There is really a readjustment in the degenerative processes and this is followed by the progressive degeneration of all the organs and tissues and a diminution in their functions.

The toute ensemble of senility is characteristic. The stature is diminished through the greater curvature of the spinal column, flattening of the pelvis, depression of the heads of the femurs and, generally, broken-down arches. A further apparent diminution in stature is occasioned by the attitude of aged persons. The head sinks down and forward, the knees are bent to maintain equilibrium and there is a general slouching appearance which is partly relieved when a cane is used. The skin becomes pale and thin and, owing to the waste of subcutaneous fat and muscle, it becomes flabby, wrinkled and falls into folds. The teeth fall out, the alveolar process in which the teeth are imbedded wastes and there is a waste of the bone substance of the lower jaw. When the jaws are now closed the lower jaw is drawn further up to meet the upper jaw and the small, weazened face of the aged is produced. The eyes become dull and there is generally a gray ring called the arcus senilis around the iris. The nose and ears become thin and pale, the lips become flaccid and darker in hue, the color being a fair indication of the extent of the blood impairment. The hair rapidly whitens or falls out but there is often a growth of hair in unusual places as in the ears, nose, chin and on the upper lip of women, etc.

The face is expressionless and it is seldom toused to reflect interest or emotion.

The mental changes in senility are peculiar. In those who have had little intelligence or education there is a gradual diminution in all mental faculties. Memory fails until the event of a moment ago is forgotten, reason and judgment are lost, interest can be aroused with difficulty and only with greater difficulty can it be maintained; only the most powerful sensory impressions are received, interpreted and get responses. The emotions are dulled, there is neither fear nor hope, joy nor sorrow, and the individual will smile or weep without apparent cause. Usually he is apathetic, gradually lapsing into a state of complete amentia in which even the fundamental instinct of selfpreservation is lost.

The intelligent, educated person generally retains reason and judgment but the mind is less active and brain fag develops rapidly. Memory is impaired, recollections of early events coming unbidden while later events cannot be recalled by any effort of the will. Old persons find it difficult to displace old ideas, habits and hobbies by new ones, and they are, therefore, called old-fashioned. Imagination sometimes develops delusions, such delusions always possessing the element of self-aggrandizement. It is difficult to arouse interest or maintain attention. Under some extraordinary stimulus mental acuity will be revived but this lasts only a short time and is followed by mental exhaustion. Weak sensations are not received owing to the impairment of the sensory organs, but the mind correctly interprets sensations that it does receive. The emotions

are dulled, there is seldom hope or joy, but usually there is a depressed, hopeless resignation to the inevitable. Sometimes religious teachings overcome the haunting fear of death, in some cases a materialistic philosophy makes the mind indifferent to death. Usually as the mind becomes weaker the fear of death and all other fears diminish; it is doubtful, however, if there is developed an instinct for death as Metchnikoff assumed.

Some individuals possess remarkable mental powers in old age. A critical study of the mentality of such individuals reveals in almost every case a concentration of mental faculties in one channel or direction while in every other direction there is profound mental impairment. The absent-mindedness and other peculiarities of these aged geniuses are really evidences of mental impairment. In the rare cases where the mental faculties retain their power with little or no impairment, the physical changes are slight and the whole process of senile involution is apparently retarded.

A remarkable phenomenon in senility is the approximation of the sexes toward a neuter type. The female chest gradually approaches the senile male chest in shape and the male pelvis becomes flattened until it resembles the female pelvis. In the male the hair on the face becomes thin while there is a growth of hair on the face of the female. His voice becomes higher, her voice becomes lower in pitch. The small weazened face and the dull expression give to both a similarity in features. It is a common observation that old couples resemble each other and through long association they exhibit similar mental traits. This phase of senility has not been sufficiently studied. While imagination undoubtedly plays a part in noting this resemblance it is in many cases sufficiently marked to attract attention. Virilescence usually begins soon after the menopause; its counterpart in the male is rarely observed before the period of senility. See OLD AGE.

I. L. NASCHER, M.D., Author of Diseases of Old Age and Their


SENIOR, sē'nyor, Nassau William, English political economist: b. Compton, 26 Sept. 1790; d. Kensington Gore, London, 4 June 1864. He was graduated from Eton and from Oxford, and in 1819 was called to the bar at Lincoln's Inn. He was the first professor of political economy at Oxford 1825–30; was appointed a master in chancery in 1836 and resumed his chair at Oxford in 1847. Of his writings, which comprise a number of excellent treatises on political economy, mention may be made of An Outline of the Science of Political Economy (1836); Political Economy? (1850); Essays on Fiction (1864); and Historical and Philosophical Essays) (2 vols., 1865).

SENLAC, sěn'lăk, or HASTINGS, Battle of, the one battle in the Norman conquest of England. It was fought 14 Oct. 1066 at Senlac Hill, a few miles from Hastings, between William, Duke of Normandy, and Harold II (q.v.), king of England. Harold's fortified position was attacked at 9 A.M. by the Norman army in three divisions, strong in cavalry and archers, the centre led by William in person. The English made a stout resistance with their battle

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axes and other weapons, but part of them pur- plants, with nearly regular, five-parted flowers suing William's flying Bretons, the whole body in racemes and alternate, pinnate leaves subwas led into a trap by the feigned retreat of divided into many leaflets. Alexandrian senna many of the_Norman forces, the disordered is formed of the leaflets of Cassia acutifolia, ranks of the English being easily overborne by which are dried by cutting the shrubs until the their enemies, who stormed and carried the leaflets shrivel and tumble off. C. angustifolia hill. The death of Harold, who was pierce grows in and about Arabia, where it was used in the eye by an arrow about sunset, disheart- in domestic practice by the Arabs, who were ened his men and they shortly dispersed. Bat- apparently the first to introduce the drug to tle Abbey was erected by William on the field Europe. It is called Indian senna, as it is where Harold fell and portions of it still exist. cultivated in South India. Bombay senna is a Among the literary treatments of the event are very inferior quality of this variety, much mixed two poems of Chatterton and a drama by Cum- with stalks and dead leaves; the variety Tinberland. Consult Green, "The Conquest of nevelly, on the contrary, is the largest and cleanEngland (1899); Freeman, Norman Con- est senna in commerce. C. obovata, formerly of quest' (Vol. III, 1876). See WILLIAM I. good repute, producing senna-pods and cultiSENN, Nicholas, American surgeon: b.

vated in India, is now classed among the infeBuchs, Switzerland, 31 Oct. 1844; d. Chicago,

rior qualities and rarely met with except as an Ill., 2 Jan. 1908. He was ught to this coun

adulterant. Still other sennas are known under try when a boy and settled in Wisconsin. He the name of the port of export, or place of was educated at the Chicago Medical College

growth. American or wild senna is the Cassia and the University of Munich, was house phy

marylandica, a perennial abundant in the southsician at the Cook County Hospital 1868–69 and

ern United States, sometimes eight feet high, practised medicine in Wisconsin 1869–93, being

with obtuse, oblong leaflets, numerous yellow one time surgeon-general of that State. flowers, with clawed petals and long linear After 1893 he practised in Chicago, where he

pods. It has the qualities of Oriental senna in was attending surgeon of the Presbyterian Hos- a lesser degree and was formerly used for the pital and surgeon-in-chief of the Saint Joseph's same purposes in popular medicine. Bladder Hospital. He was appointed in 1898 chief sur

senna is the Colutea arborescens and is also a geon of the Sixth army corps, ranking as lieu

purgative sometimes called bastard senna. tenant-colonel of volunteers and chief of staff SENNAAR, să-när', Anglo-Egyptian Sudan, in the field. From 1884–90 he was professor of

a province extending between the_Blue and surgery at the College of Physicians and Sur

the White Nile, from Khartum to Fazogl. It geons, Chicago, and after 1890 professor of

covers an area of 40,000 square miles. Generpractical and clinical surgery at the Rush Med

ally speaking, it is a broad plain with occasional ical College. He was also professor of surgery granite mountain heights and is at the north at the Chicago Polyclinic and lecturer on military surgery at Chicago University. Among bushes; the southeast has tall forests intersected

steppes thickly overgrown by wild grass and his works are Four Months Among the Sur- by fertile valleys. Gold and iron occur, and geons of Europe; Experimental Surgery)

palms, tamarinds, etc., grow on the plain, (1889); (Surgical Bacteriology) (1889); Prin

Monkeys, lions, gazelles, giraffes, elephants, beciples of Surgery'; (Tuberculosis of Bones and

sides marsh and water-birds, are numerous; Joints'; Medico-Surgical Aspects of the Span- also domestic animals. The chief occupation ish-American War); and a Nurse's Guide for

is fishing. The products are rice, grain, melons, the Operating Room? (1903).

tobacco, sugar, senna, ebony and sandal-wood. SENNA, Nelson Coelho de, Brazilian law

The climate is exceedingly warm and during yer and author: b. Serro, Minas Geraes, 11 Oct. the rainy season is unhealthful. The inhabitants 1876. He was educated at the Normal School are negroes the Funj, Nubian and Galla, and at Diamantina, Historical Institute at Rio de

of mixed races, and are sometimes classified Janeiro, São Paulo, Nichtheroy and Ceará, and according to color. Slaves are imported. Senthe Academy of Juridical Sciences, Ouro Preto. naar (pop. 18,000), the former capital, stands He has been successively secretary of the police

on the Bahrel-Azrik or Blue Nile. The other and agriculture departments of his native state, towns are Fazogl (or Famaka), Roséres, Wodprofessor of Brazilian and history at Mineiro

Medineh and Khartum. Near the latter town Gymnasium, Bello Horizonte, and vice-presi- are the extensive ruins of Soda, the ancient dent of the council of public instruction of capital of the Funj, a negro race, who migrated Minas Geraes. He served in the first, second there from Central Africa in 1500 and founded and third Latin-American scientific congresses. the Senaar kingdom, which lasted until 1821. He is member of many learned societies both

SENNACHERIB, sě-năk'ë-rib, an Assyrian of South America and of Europe. His pub

king, son of Sargon, succeeded his father on the lished works are Questões internacionães do

throne 705 B.C. Among his first acts as king Brazil' ; A Edade da Pedra do Brazil'; Elogio

was the suppression of the revolt of Babylonia literario de José Eloy_Ottoni, poeta sacro brasiliero); A Hulha Branca'; 'Los Indios

and after accomplishing this he directed his del Brazil; Contes Sertanejos?; Paginas de

arms against the Aramean tribes on the Tigris historia religiosa do Brazil'; Discursos Acad

and Euphrates, of whom he took 200,000 capemicos); A Bacia do Rio Doce, etc. He

tive. He then reduced a portion of Media, till edited Annuario Historico e Estatistico do

then independent; placed under tribute Tyre, Estado de Minas Geraes after 1906.

Aradus and other Phænician cities; advanced

against Philistia, made war upon Egypt and SENNA, a nauseous, bitter but valuable finally marched against Hezekiah,

king of purgative drug, obtained from the leaves of Judah, who had revolted. Hezekiah, terrified, several tropical species of the leguminous genus yielded in a panic, and paid the tribute exacted, Cassia (q.v.), The officinal species are shrubby namely, 300 talents of silver and 30 talents of SEÑORA AMA - SENSATION


gold On his return to Assyria Sennacherib potency of imaginative suggestion, although a made another attack on Babylonia and after- work of pure realism, it rivals in completeness ward reinvaded Judah. Having marched the universality of idealistic art. There is the through Palestine he laid siege to Libnah and customary lack of coups de théâtre, reinforced Lachish and finding that his messengers Tartan, by a contemptuous disregard of the conventional Rabsaris and Rabshakeh had failed in obtaining conceptions of the stage. The first edition apthe submission of Hezekiah, he wrote an in- peared at Madrid, 1908. Consult also Benatimidating letter to Hezekiah; but before he vente, “Teatro (Vol. XVII, Madrid 1909). could bring his forces against the city, accord- The English translation is included in the ing to the Bible record, a visitation from the third series of the Plays by Jacinto Benavente Lord during the night caused the death of 185,- (New York 1917 et seq.). 000 of his troops. In consequence of this

JOHN GARRETT UNDERHILL. calamity Sennacherib returned to Nineveh and troubled Judah no more. From Herodotus we

SENS, France, archiepiscopal city and capi

tal of an arrondissement in the department of learn of the Egyptian tradition regarding the destruction of Sennacherib's host, which is,

Yonne, situated on the right bank of the that a multitude of field mice devoured all the

Yonne River, 70 miles southeast of Paris. The quivers and bowstrings of the enemy and

city contains the cathedral of Saint Etienne gnawed the thongs by which they bound on

dating from the 12th century and a fine city

hall, which contains also a museum of precious their shields. No mention of the destruction of his host is found in the monuments of Sen

stones, a library and an art gallery. Manunacherib. This ruler was one of the greatest

factures consist chiefly of fertilizers, farm of the Assyrian kings and was not only a great

implements, leather, glue, serge, etc., and there

is considerable trade in wine, corn, hemp and warrior but also a great builder. His largest

flax. Sens was known in ancient times as architectural work was the palace of Koyunjik, which covered an area of fully eight acres.

Agenticum and later as Senones and was one Of the death of Sennacherib all that is known

of the largest cities of Gaul, vestiges of the old is contained in the brief Scripture statement of

Roman walls still being visible. Pop. about

15,000. 2 Kings xix, 37 and Isa. xxxvii, 38, from which it appears he was murdered by his own sons. SENSATION. This term is used broadly See ASSYRIA; ASSYRIOLOGY; BABYLONIA.

to designate any form of consciousness which Bibliography.- Johns, C. W. H., History originates immediately from the stimulation of of Assyria (London 1911); King, L. W., the sensory end-organs of the nervous system (Sennacherib and the Ionians) in Journal of (e.g., the eye or ear). This usage fails, howHellenic Studies, Vol. XXX. (London 1910); ever, to distinguish between sensation and sense Olmstead, A. T., Western Asia in the Reign of perception. In the narrower psychological Sennacherib in American Historical Associa- meaning sensation applies to the elementary tion, Annual Report (Washington 1911); forms of consciousness originating under the Rogers, R. W., History of Babylonia and As- conditions mentioned. Sensations are in this syria' (New York 1900); id., Cuneiform technical sense cognizant of simple sensuous Parallels to the Old Testament (New York data, such as colors, tones, etc., whereas per1912); Schrader, E., (The Cuneiform Inscrip- ceptions are cognizant of objects. For example, tions and the Old Testament (I, 278–310); we perceive a sunset, a complex visual object Smith, G., (The History of Sennacherib? (Lon- displaying various color qualities, e.g., whitedon 1878); Tiele, Babylonisch-Assyrische ness, redness, etc., of which we become conGeschichte (Gotha 1885).

scious as sensations. These sensations are reSEÑORA AMA, drama in three acts by garded as simple and incapable of further Jacinto Benavente, was acted at Madrid 23 analysis. We perceive a musical sound when Feb. 1908. The story is one of peasant life on a note is struck upon the piano. This sound the plains of High Castile, a presentation of is made up of a simple fundamental tone and contemporary rural Spain as brilliant in color, its overtones. Our consciousness of one of but sordid and dead within, palsied with the these simple pure tones is a sensation. On these degeneracy of a decaying civilization, from terms sensation is evidently largely an abstracwhich all impetus and inspiration have dis- tion of the psychologist. Our actual sensory appeared, and merely husks of Church and State consciousness is commonly cognizant of obremain. Few dramas are of equal pessimistic

jects, i.e., is perceptual. power. As a veracious psychologic study, the Certain authors extend the meaning of sensaplay is of great value, depicting the sterility

tion so as to include not only all elementary of the retarded country-side which is sunk in sense qualities arising directly from sensory jealousies, sensuality and greed, where only the stimuli, but also all such qualities when aroused maternal instinct breathes unstunted amid the in processes of imagination, as when, for ininsentient fields. The minutest details are of stance, one closes the eyes and gets a visual unimpeachable realistic veracity. The author

image of a rose. They speak, therefore, of avoids any semblance of generalization. Yet in peripherally and centrally originated sensations. the absence of physical descriptions, the aspect

In so far as this usage calls attention to the fact of the Castilian plain and sierra is projected that the sensory and ideational elements are from the austere mentality of the peasantry qualitatively alike, whether called out by central with a rudeness of coloring and distinctness of or peripheral stimulation, it is justifiable. But outline which the Spanish painters have not

well-established custom is violated by the procesurpassed. The sense of the motionless back- dure and it may be questioned whether it will ground provided by centuries of Spanish civil- endure. ization is conveyed with the same economy of The commonly recognized groups of sensa

Upon the technical side the play is tions are as follows: color, including brightone for the artist, In illuminative insight and ness, sound, taste, smell, pressure, heat, cold,


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pain, articular, tendinous, muscular, thirst, hunger, sex, circulatory (including tickling, itching, etc.), respiratory and static (dizziness sensations from the semi-circular canals of the ear).

Psychologists are wont to treat sensation under four principal aspects, i.e.,.quality, duration, intensity and extensity. Of these four quality is generally considered most basal. A sensation of tone, for example, may vary in duration without appreciable alteration of the pitch, which constitutes its most essential quality. Again, a color sensation may under certain conditions vary in extent without noticeable variation of quality. But a sensation which had no duration or no intensity would obviously be no sensation at all, and in general, if any aspect which a given sensation can manifest be reduced to zero, the whole sensation vanishes. Certain psychologists maintain that every sensation possesses all these aspects, but probably the majority hold that auditory sensations at least, and perhaps a few others, like smell, are lacking in extensity: Certain interesting facts concerning the relations of sensation intensities to one another are formulated in Weber's and Fechner's laws. (See WEBER'S Law). According to Weber equal differences in sensation intensity are produced by relatively equal differences in stimulus intensity. If we place a weight of 20 grams upon the hand, we shall notice no change until we have added another whole gram, i.e., of the original stimulus. If we take a weight of 100 grams, we must now add not one gram but no of 100 grams or 5 grams, before we notice a change. The same sort of relation holds for a number of the senses within the medium ranges of intensity.

Sensations depend upon the stimulation of specific end-organs connected with specific brain centres. No one ever gets visual experiences who does not possess an optical centre in the cerebral cortex and who has not at some time possessed a functioning retina. No one ever gets auditory experience without a similar use of the ear and the auditory cortex and the same sort of thing is true for each of the sensations.

The stimuli which produce sensation are classified as adequate and inadequate, internal and external, mechanical and chemical. The only pair which requires any explanation is the first. Each sense organ is fitted to respond primarily to some special form of physical stimulus, e.g., the eye to light, the ear to sound, etc. Such stimuli are called adequate. In addition to these adequate stimuli, however, the senses can be aroused by other forms of stimulation designated inadequate. Thus an electric current conducted to the frontal region of the head may produce sensations of light. Pressure on the eyeballs similarly occasions color sensations. It may be added that sensations often continue after the stimulus is removed. Such sensations are known as after-sensations. In the case of vision they present very remarkable characteristics and are commonly called afterimages.

Sensations combined in various ways and reinstated in the form of memory and imagination furnish the basis of all our ideas. They are accordingly the foundations upon which rests the whole structure of knowledge. To understand their function in this particular it must be borne in mind that in actual experience they are not

mere naked qualities, but that they serve to convey meanings and that it is in this manner that they achieve fundamental import for mental life.

Bibliography.- James, Principles of Psychology) (New York 1890); Külpe, Outlines of Psychology (1895); Bain, Senses and Intellect' (London 1855). For special senses see literature of special articles, Vision; ORGANIC SENSATIONS, etc.

JAMES ROWLAND ANGELL, President of Yale University, New Haven, Conn.

SENSATION, Organic. The term organic sensation is nowadays applied broadly, to all those sensations which originate from internal bodily stimulations. They are called forth by mechanical, chemical and thermal changes in the organism. Among the sensations which are commonly held to belong to this group may be mentioned pain, pressure and temperature from the interior of the organism; sensations from the muscles, tendons and joints; sensations from the alimentary, canal; sensations from the circulatory, respiratory and sexual organs; and finally sensations which are supposed to originate from the semi-circular canals of the internal ear. These sensations are sometimes distinguished from the other forms of sensation like vision and hearing on the ground that they convey to us primarily a knowledge of the state of our own organism rather than knowledge about the external world. This distinction is, however, only roughly accurate.

The sensation qualities which originate from these senses can be described only with approximate accuracy, for psychological analysis has not succeeded as yet in unraveling all their complexities. Pain, pressure and temperature are familiar experiences requiring no description. From the muscles we obtain sensations which suggest dull pressure, becoming under conditions of fatigue somewhat unpleasant and in condition of cramp leading to distinct pain. From the tendons we obtain sensations which inform us of the movement of our limbs and particularly sensations of strain and resistance. It is generally held that from the joints we receive important sensations which also inform us of the movements of our limbs and in particular make us aware of their position. Certain authorities have called in question — both on anatomical and psychological grounds — the significance of the articular sensations. These sensations from muscles, tendons and joints commonly occur together and are sometimes spoken of in a group as the muscle sense or the kinæsthetic senses. Experimental devices are necessary in order to isolate them from one another. The circulatory processes are probably responsible for such subjective sensations as feverishness, shivering, "pins and needles,” itching, tingling and tickling. Of course certain of these sensations are at times called forth by direct external causes. The heart itself occasionally gives rise to very distinct sensations, commonly of a painful character. The respiratory organs are probably responsible for our feelings of suffocation, of 'stuffiness) and closeness as well as for those of freshness and stimulation in the air. The alimentary canal occasions at least three specific qualities: hunger, thirst and nausea. Undoubtedly the processes of secretion and excretion affect the general tone of consciousness from time to time,

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