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Laryngoscope

and inhalations of steam or of nitrate of amyl, generally hasten recovery, while an emetic is frequently of service.

Laryngoscope, a small circular mirror attached at an off. of about 120° to a slender handle, by which in examinations of the §: it is placed in the pharynx with its back against the uvula, and so manipulated that its surface reflects the interior of the larynx, or, when inverted, that of the naso-pharynx. . The instrument was invented (c. 1855) by Manuel Garcia (1805), a teacher of singing, who used it primarily to observe the mechanism of his own vocal organs during phonation. (See VoICE.) Soon after its invention, Dr. Czermak, of Pesth, introduced , the laryngoscope into medical, practice, in which it is much used as an aid to diagnosis in laryngeal and postnasal o:"Ra fi

Larynx. rynx first a rs in Amphibia. #. #o. sented in the lower forms, but reaches considerable differentiation in the Anura, (frogs and toads), where vocal cords are present; and the croaking sound which , the animals produce is often intensified by sacs placed at the angle of the jaw. Reptiles do not display any advance in structure as compared with amphibians. In birds, the conditions are remarkable, for an upper and a lower larynx are both present. The lower larynx or syrinx is the organ of voice, and is of colnlicated structure. It lies at the ower end of the trachea, or at its junction with the bronchi. A structure, homologous, with the larynx of other vertebrates lies at the top of the trachea, but it is rudimentary, and is incapable of producing sound. The larynx is well j in all mammals, and is peculiar in always possessing an epiglottis and a thyroid cartilage. he muscles are also very well developed as compared with other vertebrates. In certain of the Primates—e.g. the howling monkey (Mso and the orang—there are large resonating chambers connected with the larynx. In man, the larynx lies in the upper and front part of the neck, between the base of the tongue and the upper end of the trachea. It consists cf a tubular framework of nine car*: which are connected with each other by joints, membranes, ligaments, and muscles. The largest of these cartilages is the thyroid, which is shield-shaped, and consists of two lateral wings diverging from a vertical central ridge in front. The upper part of the ridge forms the pomum Adami or Adam's apple of the throat, and is more prominent in men than in women, because of

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the greater size of the thyroid cartilage in the male sex. Above and in front of the thyroid cartilage is a thin leaf-like structure, the epiglottis, which during ordinary respiration stands erect at the back of the tongue, but durin the act of swallowing is joi backwards and downwards so as to bridge over the upper opening into the larynx and ensure the passage off into the gullet behind. he laryngeal cavity is lined with mucous membrane continuous with that of the pharynx above and the trachea ies. ut in the larynx the membrane has a double reduplication on each side.

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larynx, which in life plays the F. of a resonating chamber.

n order that sound wayes may be formed, the vocal cords must be parallel, and have a current of air passing between them; they must also be more or less tense, and the pitch of the musical note depends upon the degree of tension of the vocal cords. The range of a voice depends on the extremes of tension which can be imparted to the cords, while the yocal quality is determined by their len o and elasticity as well as by the form and size of the resonating chambers. In ordinar ech the larynx is concerned with the pro

The Larynx.

1. Lateral "To: 2. Vertical section. 3. Vocal cords seen from above during breathin 4. e same during phonation. 5. Longitudinal section of larynx seen from

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*; B, cricoid cartilage

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The upper , folds, cover delicate fibrous bands and form the false vocal cords, which get the name “false’ because they are not directly concerned in the production of voice. The lower pair of folds are the true vocal cords, and enclose strong fibrous bands of elastic tissue, known as the inferior thyro-arytenoid ligaments which run from the irytenoid cartilages behind to meet anteriorly at the centre of the thyroid. Parallel with and outside these #". lie the thyroarytenoid muscles, whose contraction relaxes the vocal cords. Between the false and the true cord on , each side lies a pouchlike cavity, the ventricle of the

duction of those consonants which are voiced and of all the vowels, whose differences depend upon adventitious sounds formed by the tongue or , lips, or on the introduction of different combinations of harmonics by alterations in the resonating chambers, the mouth, and the pharynx. The chief o affections of the larynx are (1) new formations, (2) paralysis, and . various forms ..P. itis. The larynx is frequently the seat of new formations of a simple, nature, such as warty growths and Ho: or, on the other hand, malignant and cancerous. Paralysis of one or both vocal cords may result from pressure upon Lasalle

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the laryngeal nerves by , aneurisms or other swellings in adjacent organs. Laryngitis may be acute, and may be merely a part of a general catarrh of the respiratory mucous surfaces; or it may be more chronic, as in the form known as clergyman's sore throat. An oedematous type of laryngitis also occurs, and is attended...by special danger, as the swellin may lead to great dyspnoea an even to fatal suffocation. In grave cases, early intubation, is advisable. most intractable and painful form, of laryngeal disease is tubercular o which, as a rule, occurs only in patients already the subjects of pulmonary tuberculosis. Direct injuries to the larynx are most usually caused by foreign bodies drawn in by an inspiration during the act of swallowing. A pin or a tack is apt to cause oedema, while a coin may lie horizontally on the cords and thus choke the patient. Should the foreign body not be cqughed up, removal with the aid of a laryngoscope and appropriate forceps may sometimes be successfully carried out, but generally tracheotomy is necessary. See also CROUP. La Salle, city, La Salle co. Ill., on th: iii.ois R. and the Illinois and Michigan Canal, and on the Chi., Rock I. and Bac. the Ill. Cent. and the Chi., Burl. and uin. Rs., 85 m. w.S.w...of icago. Its manufacturing industries include zinc rolling mills and zinc smelting works, and manufactures of clocks, brick, cement, glass, ploughs and farm machinery. Čoãi mining is an im: portant industry, and ice is shipped to the South. The city has a ublic library, and St. Mary's ospital. Features of public interest are a new city hall, the Illinois Central Railroad bridge m. long, a wagon bridge an eer Park Glen. The water works and electric light, plant are owned and operated by the municipality. LaSalle was settled about 1837 and named after Sieur de La Salle, the great FrenchCanadian explorer. Pop. (1900) 10,446; est. (1903) 10,623. La Salle, Rob ERT CAVELIER, Sieur de (1643–87), famous French explorer in N. America, the first mān to pass down the Mississippi river from the French possessions in the north to the Gulf of Mexico. He was born at Rouen, France; went to Canada in 1666, and in 1669 endeavored to reach the South Sea or Pacific Ocean by way of the Ohio, which river he discovered and followed probabl as far as the Falls (at i.;; He is, remembered, however, chiefly for his expedition of 1678– 82, during which, after overcoming manifold hardships and show

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ing indomitable perseverance, he reached the Mississippi river by way of the Great Lakes and the Illinois, river, establishing a fort (Fort Crèvecoeur) on or near the site of the present Peoria, Ill and leaguing o: the filinois Indians to fight back the Iroquois, and passed down the Mississippi river (1682) from the mouth of the Illinois to the Gulf of Mexico, taking possession of , the region about the mouth of the river for Louis XIV., in whose honor he called the surrounding country “Louisiana.’ Returning to Canada, he went, thence to France and persuaded Louis XIy. to send him on another expedition whose object was the construction of forts at the mouth of the Mississippi and the o: of Spaniards who might found in the region. . He left La Rochelle, France, in July 1684, and, missing the mouth of the Mississippi, established a fort on what is now the Lavaca river in Texas. Thence he vainly attempted to reach the ..p. and, while on his way overland to Canada, was assassinated (Mar. 19, 1687) near the Trinity river in Texas. His colony, in Texas was soon destroyed by disease and by Indian attacks. See Parkman's La Salle and the Discovery of the Great West (1879); Shea's Discovery and Exploration of the ...Mississippi Valley (1852), and Winsor's Cartier to Frontenac (1894). La Salle. College. An institution established in Philadelphia in 1863 for the higher education of Roman Catholics, and conducted by the Brothers of the Christian schools. It has collegiate commercial, academic, and preparatory departments, with a total attendance in 1905 of 153, when the faculty numbered 17 and the library contained 10,000 volumes. Lascar (a camp-follower or soldier; from Hindustani , and Persian lashkari) is now freely applied to sailors of East Indian birth serving on European ships. Lascaris, CoNSTANTINE (d. c. 1493), a pioneer of Greek learning in the West. Reaching Italy from Cole (1454), he taught successively at ilan, Rome, , Naples, and Messina, in which latter town he died. His Greek grammar, Erotemata (1476), was the earliest printed Gree book in Italy. Las Casas, BARTOLOMé DE 1474–1566), bishop of Chiapa Mexico, called the “Apostle o the Indians,’ was born at Seville. After studying at the University of Salamanca, , he joined an exon of Columbus to the W. ndies (1498–1500), and subsequently went to Haiti, where he took holy orders. Repairing to Cuba (1511), after a time he re

Lasker

turned to Spain to protest against the prevalent system of employing Indians as slaves. After 1530 he worked incessantly in various parts of Central America, especially in Tuzuluthan, where The successfully established Christian worship and doctrine. After some years spent in Europe, he accepted the bishopric of Chiapa in 1544. He left an unfinished Historia general de las Indias, #. in the “Coleccion de ocumentos inéditos para la Historia de España' (1875–6); Veynte Razones (Twenty Reasons’ in support of Indian freedom); Brevissima Relación de la Destrucción de las Indias (1552), and other works. His CEuvres Complètes appeared in Paris (1822). See H. y Sir Arthur Helps (1868), Prescott's Conquest of Mexico (1843), and Winsor’s Narrative and Critical History of America, vol. ii. (1889).

Las Cases, EMMANUEL AUGUSTIN DIEUDoNNé MARIN JoSEPH, Count DE (1766–1842), French historian, born near Revel in Languedoc; entered the navy,

but fled to England during the revolution. After Napoleon's accession to power he returned to

France, and labored at the comletion of his Atlas Historique 1803–4; new ed. 1826). For this work Napoleon made him a baron, employed him in the home administration, and gave him the office of chamberlain. After Waterloo he accompanied the ex-emperor to St. Helena, and there wrote at his dictation the Mémorial de Sainte Hélène (1821–3). See his Mémoires (1819). Las Cinco Villas, a designation for the Centras portion of Cuba, containing, the five towns of Sagua la Grande, Santa Clara, Remedios, Trinidad, and Cienfuegos, and extending, perhaps, as far E. as Santiago prov.

Lasco, JoHANNEs A, or JAN LASKI (1499–1560), , Polish reformer, born at Piotrkow. His

uncle, archbishop of Gnesen, conferred many benefices, on him; but in 1538 he left Poland, and settled at Emden, where he founded a reformed church. In 1550 he accepted an invitation from Archbishop Cranmer to become pastor of the Dutch church of Austin Friars, London. Dalton's John & Lasco (1886). La Serena, city, Chili, cap. of prov. Coquimbo, at the #&# of the Coquimbo river, 7 m. from the port of Coquimbo. It has smelting works. A U.S. consular agent resides here. Pop. (1895) 16,500. Lashkar. See Gwalior. Lasker, EDUARD {s}. * German publicist, of Jewis parentage, filled some posts in the Prussian law courts, and in 1865 entered the Prussian legislature. member also of the German Parliament from 1867, Lasker

he became , a leading spirit of the national Liberal o . He strove earnestly towards the unification of Germany, and took a chief part in remodelling the judicial system (1867–77). uring a visit to the U.S., in search of health, Lasker died in New York, Jan.5, 1884. The action of Bismarck in returning undelivered through the German min: ister at Washington resolutions of condolence passed by the House of Representatives and forwarded to Minister Sargent at Berlin for presentation to the Reichstag, gave rise to what is known as ‘the Lasker incident.” Lasker's chief publication was Zur Verjas*::::::::::::: Preussens Wo: a collection of essays. See Wolff's Zur Erinnerung an Eduard Lasker (1884); Freund's Einiges iiber Eduard Lasker (1885), and the study by Bamberger (1884). Las ker, EMANUEL (1868), German chess player, born at Berlinchen, Brandenburg. , His achievements first attracted attention at the Nüremberg tournament (1883), and became still more notable at Breslau {:}} Nüremberg (1896), London (1899 #..." "Hoo. defeated Blackburne in London §§ and Steinitz in America (1894), winning the return game at St. Petersburg (1896), an first prizes in tournaments in several cities (1892–1900). Lasker has published Common Sense in Chess (1896), and some mathematical essays. Las Palmas, chief th: on N.E. shore of Grand Canary Is., prov. Canaries, Spain, 60 m. from Santa Cruz de Tenerife, the seat of government. The fine harbor of Puerto de la Luz is 3 m. distant, and can shelter vessels of the deepest draught. . It is, connected with the city by railway. There is an interesting 16th-century cathedral. Industries include fishing and the manufacture of glass, hats, and leather goods. Exports bananas, potatoes, tomatoes, and oranges, wine,...sugar, cochineal, and onions. ‘the city is a port of call for several lines of ocean-going steamships. Pop. (1900) 44,517. Lassa. See LHASSA. Lassalle, FERDINAND (1825– 64), the most brilliant and picturesque of German socialists, was foremost among the founders of the Social Democratic party in Germany. Between the ideas and methods of Marx and those of Lassalle there is great difference. Marx was an internationalist; Lassalle was an ardent patriot, a fanatical advocate of German unity, which gave him influence over Bo: and liberalized Prussian domestic politics for a time. The Social Democratic }. which he and Marx jointly ounded adopted Marx's collect

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to a close at the early age of thirty-nine. He was much more than an agitator; he was a scholar, a man of fashion, and a gallant. The story of his life is the basis of Meredith's novel, The Tragic Comedians. Bernstein’s edition of Lassalle's works (Eng. trans., 1893), which includes a biography, is considered the best. See Dawson’s German Socialism and Ferdinand Lassalle (1899), and Ely’s French and German Socialism (1883). Lassell, WILLIAM (1799–1880), English astronomer, was born at Bolton, Lancashire. He built an observatory at Starfield, near Liverpool, and constructed a two-foot speculum, with...which he discovered the satellite of Neptune (1846). , The same instrument disclosed Saturn's eighth satellite, Hyperion so and the inner Uranian satellites, Ariel and Umbriel (1851). In 1861 he mounted a four-foot equatorial reflector at Malta, and catalogued with it, during three years, six hundred new nebulae. Lassen, CHRISTIAN (1800–76), Norwegian Orientalist, born, at Bergen. . At Bonn , he studied under Schlegel, collaborating with him in the publication of the Rāmāyana and Hitopadesa. Becoming professor of Indian lano: and literature there (1830), e devoted himself to elucidating Persian cuneiform inscriptions, and to other kindred recondite subjects. His monumental work is the Indische Altertumskunde (1844–61). Lassen, EDUARD (1830), Danish musical composer, born at Copenhagen; became widely known in Belgium for several notable operatic works and Popo. Songs. After the retirement of Liszt from the Court Theatre at . Weimar, the baton was transferred to Lassen, and he there successfully o: Wagner's Tristan and solde (1874). He is the comser of the op. Le Roi Edgard o by Liszt, 1857), Frauen5 (isoo), Le Captij (1865), a ballet Diana, much incidental dramatic music, and a great number of songs. Lasso, a plaited rope of raw hide, hair, or hemp, provided with a running noose at one end, and used by ranchmen and others for capturing or bringing down cattle. Throwing the lasso requires considerable dexterity. he user, who is mounted, causes the open noose to revolve rapidly, and then throws it forward over the head or horns of the desired animal, retaining the rest of the lasso in coils in his bridle hand. Las Tablas, th:, republic of

Lateau

Panama, situated on the Azuero Peninsula, 108 m. S.W. of Panama. Pop. 6,000. Lasus, Greek lyric poet, was a native of Hermione in Argolis and is famous as the teacher o Pindar. Only three lines of one 9f his poems remain, which can be found in Bergk's Lyrici Graci. Las Vegas, city, N. Mex., Co. seat of San Miguel co., in the N.E. of the Territory on the plains at the E. base of the Rocky Mts., and on the A., T. and S. Fé R. R., 70 m. E. of Santa Fé. It has manufactures , of brick, cigars, carriages, machine-shop products, etc. . It is, an important wool market and also ships sheep and cattle. It is the seat of the New Mexico Normal University. Other institutions , include a Carnegie jo, St. *#. Sanitarium, the Las Vegas Hospital, Santa Fé Hospital, Territórial Insane Asylum, and various sanitariums. The old Santa Fé trail passes through here and is a remarkable mountain road. The old Spanish manor houses are also of scenic interest. Hot springs, 6 m. distant, are much resorted to. The altitude of the hot springs is 6,714 ft. Pop. (1900) 3,552. Las Villas, a designation for a Fo of Cuba embracing Santa lara and parts of the provs. of Puerto Principe and Matanzas. Latacunga, chief th: in Leon prov., Ecuador, S. America, in the Andes, between Cotopaxi and Chimborazo, 56 m. S. of Quito. It has frequently been destroyed É. earthquakes, notably in 1797. ontains former palace of the Incas. Trade in saltpetre. Alt. 9,120 ft. Pop. 15,000 (mostly Indians). Latakia, or LADIKIYEH (anc. Laodicea ad Mare), seapt. in Beirut vilayet, Syria, opposite the N.E. corner of Cyprus. Exports barley, cotton, wax, sponges, and the famous Latakia tobacco. Pop. about 22,000. Latania, a genus of fan palms, natives of the Mascarene Is. They are tall-growing, bearing at their summit a tuft of handsome, longetioled, palmately flabelliform caves. ale and female flowers are borne on separate plants. The chief species are . L. Loddigesii, $o: to a height of about ten eet, the leaves '...}.}}| three feet long; L., Verschaffeltii, with pale green leaves with yellow ribs; and . L., Commersonii, with deeply-incised leaves, which are employed in hat-making by the natives. Lateau, Louise (1850–83), Belgian peasant who attained notoriety (1868) on account of her claiming the appearance at periodic intervals of stigmata, or marks on the skin similar to those on the body of our Lord—a condition known to physiologists as Lateen-sail

‘stigmatic neuropathy.' Periodic bleeding of the stigmata every Friday was a feature of Lateau's case. See Warlomont's Raport médical sur la Stigmatisée 1875).

Lateen-sail, a triangular sail extended on a yard which is slung about one quarter from the lower end to a mast, and rigged in such

Boat with Lateen-sail.

a way that the upper end is raised in the air, and the lower end is brought down to form the tack. The word is merely a corruption of ‘latin,' and the rig is mainly used in the Mediterranean and on sailing canoes and small boats. Latent Heat, the name given to the amount of energy which is absorbed by unit mass of a substance as it changes its state from solid to liquid or liquid to vapor. The change is usually o: the application of heat, and what is observed is that as the change of state is being accomplished the temperature of the mixed states does not change. The explanation of the phenomenon follows at once from the modern view that heat is a form of energy. To liquefy a solid or vaporize a liquid, work must be done in removing constraints, and it is in the doing of this work that energy in the form of heat is consumed. In the reverse processes of liquefaction of vapors and oliáš. of liquids, energy in the form of heat is set free. This is usually done by direct abstraction of heat. When, however, these changes of state occur independent of any direct operation of cooling, there is evolution of heat, and the temperature rises. In like fashion, liquefaction of solids and evaporation of liquids are necessarily accompanied by a cooling effect. See HEAT. o: John, a celebrated church in Rome, regarded as the first and most illustrious in the Roman Catholic communion. It stands on a site originally occupied by the palace of the Laterani family, which palace was confiscated by Nero, and subsequently

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was ordained as the patrimony of the popes of Rome by Constantine, ...? was occupied by them till the 14th century. The present structure is of composite character, but includes a few fragments of the basilica built by Pope Sylvester I. in 324. Here five oecumenical councils have met, hence called Lateran councils.

Laterite. Laterite is a fine red or brown earth, a characteristic surface accumulation of tropical countries such as India, Arabia, and the Sahara. Many laterites are rich in iron oxide; others are aluminous. They are formed by the decomposition of the underlying rocks in tropical climates.

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dent naturalist, he was one of the founders of the Linnaean Society in 1788. Among his works are A General Synopsis of Birds 1781–5), Index Ornithologicus 1790), and A General History of irds (1821–8). Latham, Robert GoRDON (1812–88), English philologist, ethnologist, and physician, born at Billingborough, Lincolnshire; became professor of English in University College, London, in 1839. #. was the author of English Language (1841), Natural History of the Varietics of Mankind (1850), Man and his Migrations (1851), and The Nationalities of Europe (1863). He was one of the first to suggest a Role European origin for the ryans. i.athe, a contrivance for shaping or ‘turning’ wood, metal, or ivory into forms of a circular or oval section. . The simplest form of lathe, and one which is still generally used in India, consists of , two rigid centres, between which the object is revolved by means of a piece of cord wound round it, and pulled alternately backwards ...?' forwards. The ‘dead-centre’ lathe, which was commonly used early in the last century, was , but a modification of this primitive form, preserving its chief drawback of an alternating motion. In the modern wood - working lathe power is derived from a main shaft by means of belt and cone pulleys, which allow, a variation of speed, thus enabling the operator to secure ractically the same surface speed or an object of small as for an object of large diameter. An object which is to be shaped externally is fixed between , the projecting chisel-shaped end of the mandrel and the point of a movable dead-centre clamped to the bedÉ. being rigidly attached to the rst and free to revolve on the latter. With an object which re

Lathraea

quires internal boring, or turning at the end, the dead-centre is disnsed with, and a chuck or older introduced, in order to form a firm connection with the mandrel, For turning large pieces many lathes are equip so that the chuck may be attached to the outside end of the spindle. The tools are then brought into contact with the work over a steady rest on an iron stand conveniently, placed on the floor. For turning metal a, “slide-rest” is employed. This is fixed on the bed-plate of the lathe, along which it is moved by means of a longitudinal screw. An in-andout motion, is given to the upper part—which holds the tool, and slides on the lower portion—by a

Lathe for Wood-turning.

transverse screw. The slide-rest can be made to travel automatically along the bed-plate, thus taking off a complete cut for the full length at each position of the tool. modification of this principle governs the action of the screw-cutting lathe. For the production of small lots of work when the operations are mostly of the , nature of facing, the turret lathe is used. The turret takes the place of the tailstock and revolves about a conical stud firmly fixed in the turretslide. The turret contains a number of tools which are revolved into position for various operations. For the production large quantities of accurate small work of the same kind, the turret is made to operate automatically. . Such machines are used to make machine screws, etc., and hence derive their name ‘Automatic Screw Machines.’ See Horner's English and American Lathes (1900), Lukin's and Hasluck's Lathe Work o Lathom, E. and timship., Lancashire, England, 13 m. N.E. of Liverpool. Lathom House, the seat of the Earl of Lathom, is built in the Italian style. The original mansion was famous for its gallant defence by Charlotte, Countess of Derby, in 1644, when she held out against Prince Rupert for four months. Lathraea, a genus of leafless herbaceous plants belonging, to the order Orobanchaceae. #h. are natives of Europe and temperate Asia, and are parasitic on

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SOME MODERN TYPES OF LATHES.

1. Motor-driven lathe, 2. Gun-boring machine: the boring bar is ::::::::::::...' the gun revolves. 3. Screw-cutting lathe. 4. Gun-turning lathe, with arrangement for turning the taper parts. 5. Facing lathe.

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