miles in winter. Its average velocity ranges from 40 to 50 miles per hour.

Nimbus (N.).- Rain cloud. Dense masses of dark formless clouds with ragged edges, from which generally continuous rain or snow is falling. Through the breaks in these clouds there is almost always seen a high sheet of cirro-stratus or alto-stratus. If the mass of nimbus is torn up into small patches, or if low fragments of cloud are floating much below a great nimbus, they may be called "fractonimbus" ("scud" of the sailors).

As soon as rain falls from a cloud it is called a nimbus, whatever its form before the beginning of rain, with one exception, namely, when rain begins to fall from a lofty cumulus cloud it is called a cumulo-nimbus to distinguish it from a system of pure nimbus clouds, the latter being flatter and more in the nature of a sheet cloud.

Colors of Clouds.-The brilliant colors sometimes assumed by clouds at sunrise and sunset are probably caused by selective absorption and reflection of light by dust particles or vapor haze in the atmosphere. The clouds of the day-time, especially those having a great elevation, are white, since they reflect the greater part of the light incident on them.

The bases of cumuli are generally of a dark shade, while the portions in shadow are mostly of a pearl gray.

Thunder clouds sometimes have an olivegreen tint, and this is thought by some observers to portend high winds and heavy rainfall.

Utilization of Clouds in Weather Forecasts. This topic has been the subject of considerable study by Ley, Abercromby and others in Europe, and by McAdie, Clayton and the writer in the United States. In forecasting weather changes from synoptic charts the clouds frequently show the advance of a cyclonic disturbance, but not before the same information is given by the circulation of the surface winds and the fall in the barometer. Unfortunately it is not possible to fully describe and telegraph the significant features of the various cloud forms so that they may be available at a central weather station; in the case of a solitary observer, however, some skill in making local predictions of the weather may be attained by a careful study of cloud forms in connection with the barometer.

Methods of Observation.- The kind, amount and direction of clouds form a part of meteorological observations whether made for purposes of weather forecasting or for purely climatic studies. In the last-named event it is chiefly desired to know the extent of sky covered with cloud on the average of the season, since one is then able to judge of the nature of the climate with respect to sunshine. In weather forecasting it is important to know, not only the kind of cloud observed, but both its direction and apparent velocity, although in actual practice the last named is rarely attained. This information is best obtained by means of the nephoscope. An excellent form of nephoscope was devised by Prof. C. F. Marvin, United States Weather Bureau, in 1896. Professor Marvin's nephoscope is shown in the illustration.

The circular frame, A, is mounted upon three leveling screws, and its upper surface is graduated to degrees, numbered from 0 to 360, the numbers increasing in a direction contrary to the direction of motion of clock hands. The

plate and mirror, M, revolve smoothly within the circular rim, A, being carried upon a hollow vertical axis at the centre. The arm, B, carrying the sighting staff, S, also revolves upon the central axis, the outer end traversing the narrow annular space between the mirror and graduated rim. The staff, S, is telescopic in construction, and is attached to the arm at B by a hinge which permits the staff to be inclined from the vertical to any extent, but always in a plane perpendicular to the mirror. The top portion of the staff is provided with a crosshead, which is surmounted by a small sighting-knob, s. The crosshead is adapted to receive the secondary staff, S', which slides with gentle friction through the crosshead, and is tipped at either end with small secondary sighting-knobs, s′ and s". By reason of the telescopic construction of the staff, S, the crosshead cannot only be turned about in any direction, but it and the sighting-knob, s, can be raised by various amounts, being held in place by friction. The hinge at B is made in such a manner that when the staff, S, is placed in a vertical position, the small rod sliding inside can be forced down into a hole in the hinge, the effect of which is to lock the hinge so that the staff is held rigidly in a vertical position. In using the nephoscope the observer looks

down upon the mirror, M, and observes the reflection of the cloud. By moving his eye he brings a point of the cloud image and the reflection of the sighting-knob, s, into coincidence at the centre of the mirror. The head should be held so that the knob is always seen at the centre of the mirror. The cloud image will then appear to move away from the centre of the mirror. The mirror is then revolved until the graduated line becomes parallel with the motion of the cloud, when its direction of motion may be read off and its apparent velocity determined by timing the image as it passes along the graduated scale of the mirror.

Other forms of the nephoscope have been devised and used, mostly in European countries, and Prof. Cleveland Abbe, of the United States Weather Bureau, has devised a very convenient form of nephoscope for use on vessels at sea.

In determining the height of clouds, direct observations of their angular altitude are made by two observers at the ends of a measured base-line, whence the altitude may be computed by trigonometric formula. The same results may be obtained by photography, but the method is not so direct and the computations are more laborious. Consult Clayden, Cloud Studies' (London 1905). The literature of the subject

is to be found in the reports of weather bureaus and in meteorological journals.

ALFRED J. HENRY. Professor of Meteorology, United States Weather Bureau.

CLOUDS, The, a comedy by Aristophanes; acted in 423 B.C. It is an attack on the new spirit of intellectual inquiry with Socrates as the general type of faulty teacher. The "Sophists" whom Aristophanes attacks are those who delved in science and the professors of letters and rhetoric. Though one of the most interesting and poetic of the author's plays, the people refused to hear it a second time. But its literary popularity counterbalanced its failure on the stage.

CLOUET, kloo-a, French family of artists, descendants from Flemish ancestry. 1. JEHAN, ya'hän, the first known of the family,

was in 1475 a resident of Brussels. His works are unknown. 2. His son JEHANNET: b. 1485; d. 1541. He migrated to France and located at Tours. In 1518 he went to Paris and became court painter and valet de chambre to Francis I. A portrait of the King, in the Louvre, is said to have been painted by this artist, also another portrait of the King, in the Pitti Gallery, Florence, is credited to him. Several other pictures in European galleries are said to have been painted by him. In all the style is that of the Flemish school. 3. FRANÇOIs, son of Jehannet: b. 1510; d. 1572; succeeded his father as court painter to Francis I and retained the position under Henry II, Francis II, Charles IX and Henry III. He executed the wax masks of Francis and Henry II. His portraits are mostly unknown but many have been attributed to him, among them full lengths of Henry II (Uffizi), Charles IX (Vienna), Elizabeth of Austria (Louvre) and a miniature of Catherine de Medici (Vienna Museum). His works are mentioned in the records of the court. Some authorities mention a brother of François, but of him nothing positive is known. Consult De Laborde, Léon, La Renaissance des arts à la cour de France' (1855); Grandmaison, Les Arts en Touraine' (1870).

CLOUGH, klō, Anne Jemima, English educator: b. Liverpool, England, 20 Jan. 1820; d. Cambridge, 27 Feb. 1892. She was a sister of Arthur Hugh Clough (q.v.), and after a girlhood spent in Charleston, S. C., opened a day school at Liverpool in 1841. Becoming interested in the general subject of education, the North of England Council for Promoting the Higher Education of Women was founded through her efforts, and from this sprang the idea of the Cambridge higher local examinations. Lectures for women having been established at Cambridge in 1869, Miss Clough, in October 1871, took charge of a house of five women students, out of which grew the present Newnham College, over the administration of which she presided until her death. During her busy career she accomplished much for the higher education of English women. Consult Clough, B. A., 'Memoir of Anne J. Clough' (1897).

CLOUGH, Arthur Hugh, English poet: b. Liverpool, 1 Jan. 1819; d. Florence, Italy, 13 Nov. 1861. He studied under Arnold at Rugby, then at Balliol College, Oxford, and became a fellow of Oriel College in 1842. In 1849 he became head of University Hall, Lon

don, but resigned in 1852 and went to America, where he lived for a few months at Cambridge, Mass. On his return next year he was appointed an examiner in the education office. His poems were published, along with a genial memoir, by F. T. Palgrave in 1862; his poems and prose remains, with letters and a memoir, 'The were published by his wife in 1869. Bothie of Tober-na-Vuolich' (1848) is his best known poem; others are Dipsychus and 'Amours de Voyage.' They are masculine and vigorous in tone and contain many noble thoughts and strokes of genuine humor, alternating with passages of deep pathos and tenderness. He is affectionately commemorated in Matthew Arnold's 'Thyrsis' and 'Scholar Gipsy.'

CLOUGH-LEIGHTER, Henry, American composer, editor and organist: b. Washington, D. C., 13 May 1874; the agnomen of Clough was given at birth for perpetuation (together with his father's name) as family surname. He was educated privately and at Columbian University (Washington) 1887-89; at the age of 13 he obtained a scholarship at the latter university but relinquished it to give his whole time to the study of music. He became a pupil of Trinity University, Toronto, Canada, in preparation for musical degree; studied harmony, counterpoint_and_composition under Dr. Edward Kimball, Dr. George Walter, Henry Xander (of Stuttgart Conservatory of Music, Germany) and Dr. J. Humphrey Anger, of Oxford, England. He began piano study at the age of 4, under his mother, a thorough musician and a cultured_gentlewoman of high scholarly attainments. From the age of 9 to 12 was solo chorister in Saint John's Church, Washington. At 13 he began the study of the organ under Dr. Walter. At 14 was organist of Saint Michael's, and All Angels (Washington); at 15 organist of Church of the Incarnation (Washington); at 18 organist and choirmaster of Epiphany Chapel (Washington); from 1892 to 1899 was organist and choirmaster of Epiphany parish (Washington, D. C.) and also of the Jewish synagogue; from 1899 to 1900 organist and choirmaster of Grace Church, Providence, R. I.; 1900 to 1901 organist and choirmaster of Christ Church and supervisor of the music courses in the schools of Westerly, R. I. During the same year (1900-01) he was instructor of musical theory of the Howe School of Music, Boston; associate editor on editorial staff of Oliver Ditson Company, Boston, 190108; became organist of the First Parish Congregational Church, Milton, Mass., in 1901; musical editor of the Boston Music Company since 1908. His published works include five cantatas for voices, with organ or orchestral accompaniment; lyric-suite, The Day of Beauty,' for solo voice, piano and string quartet; symphonic ballad, 'Lasca,' for voice and orchestra; victorian ode, 'Recessional,' for large chorus and orchestra; many song-cycles; over 100 art songs, and a like number of choral works. He is also widely known as editor of innumerable musical, technical and pedagogical works.

CLOUS, klous, John Walter, American soldier: b. Germany, 9 June 1837; d. New York, 1 Sept. 1908. He came to America in 1855, enlisted in the United States army 2 Feb. 1857, and was promoted second lieutenant 29

Nov. 1862. He took part in the siege of Yorktown, the Seven Days' battles in June 1862, Malvern Hill, Second Bull Run, Antietam, Fredericksburg, Chancellorsville and Gettysburg, being twice brevetted for gallant conduct at the latter. He served on the frontier and in Indian campaigns 1868-86, as judge advocate in many important trials and cases 1862-86, was assistant to the judge advocate-general 1886-90 and professor of law at West Point 1890–96. During the Spanish-American War he was ap pointed a brigadier-general of volunteers and served on the staff of Major-General Miles. He attained his lieutenant-colonelcy 12 Feb. 1892. He was the author of lectures on 'Military and Martial Law and Suspension of the Writ of Habeas Corpus,' delivered at Union College in the Butterfield lecture course.

CLOUTIER, kloo'tya', François Xavier, Canadian bishop: b. Sainte Geneviève de Batiscan, 2 Nov. 1848. He was educated at Three Rivers and Laval University, and ordained to the priesthood in 1872. He was consecrated bishop of Three Rivers 25 July 1899.

CLOVE, the unexpanded flower-bud of an East Indian tree (Eugenia aromatica) somewhat resembling the laurel in its height and in the shape of its leaves. The flowers grow in clusters, and the petals are small, rounded and of a bluish color; the fruit is an oval berry. The Molucca Islands, where the raising of different spices was formerly carried on by the Dutch colonists to a great extent, appear to be the native land of the clove, and the best are still brought from that quarter. At one time, however, in order to secure a lucrative branch of commerce in this article to themselves, the Dutch destroyed all the trees growing in other islands and confined the propagation of them to that of Ternate. But both clove- and nutmeg-trees were transplanted from the Moluccas into the islands of Mauritius and Bourbon, and the clove is now cultivated with success in many warm countries, including Zanzibar and the West Indian islands. At a certain season of the year the clove-tree produces a vast profusion of flowers. The operation of gathering is performed between the months of October and February, partly by hand, partly by hooks and partly by beating the trees with bamboos. The cloves are subsequently dried by exposure to the smoke of wood fires, afterward to the rays of the sun. When first gathered they are of a reddish color, but by drying they assume a deep-brown cast. This spice yields a very fragrant odor and has a bitterish, pungent and warm taste. It is most frequently used in culinary preparations. When fresh gathered, cloves will yield, on pressure, a fragrant, thick and reddish oil; and by distillation a limpid essential oil.

The medical value of cloves is due to the presence of eugenol, C10H12O2, in the volatile oil. Eugenol is extremely active, acting like the phenol, or carbolic acid group, to which it is related. Clove is a marked local anesthetic, a strong antiseptic and bactericide, an excellent stimulant to the sympathetic nervous system, expelling flatus from the stomach and the intestines, by increased peristalsis, and increasing the flow of the gastric and intestinal juices. Its value in toothache is due to its anæsthetic and bactericidal properties. A number of new compounds of eugenol are on the market. Ben

zoyl-eugenol and cinnamyl-eugenol are used in the treatment of tuberculosis.

CLOVE-BARK, the bark of various aromatic trees, used in the manufacture of drugs and spices. A tree (Dicypellium caryophyllatum) of Brazil supplies a cinnamon-like cylinder which is commonly known as clove-bark in the American markets and is used in medicine as cassia caryophyllata. The name is often given also to culilawan and cinnamon.

CLOVE-PINK, or CLOVE GILLY FLOWER, the carnation (Dianthus caryophyllus), more especially a whole-colored, clovescented variety of it.

CLOVER, Richardson, American naval officer: b. Hagerstown, Md., 11 July 1846. He was graduated at the United States Naval Academy in 1867. He was advanced through the various grades, attaining that of rear-admiral in 1907. He had charge of the survey of southeastern Alaska in 1885-86, was hydrographer at the Bureau of Navigation 188993 and chief of the Office of Naval Intelligence 1897-98. He commanded the Bancroft during the war with Spain and afterward returned to the Naval Intelligence Office. In 1900-03 he was naval attaché at London, and in 1906-08 was president of the Board of Inspection and Survey. He was retired 11 July 1908.

Of

CLOVER, species of the genus Trifolium, belonging to the pea family (Fabacea). Trifolium about 400 species have been described; they are most abundant in the north temperate zone, a few in South America and South Africa. Some are very important in agriculture, either for pasturage, fodder or for soil-improvement.

The word "clover" is also applied to species of related genera, as bur-clover (Medicago), sweet clover (Melilotus), bush and Japanese clovers (Lespedeza), prairie clover (Petalostemon), etc.

The true clovers (Trifolium) are herbs with mostly three-foliolate leaves; purple, pink, white or yellow small flowers in dense heads or spikes; and straight membranous pods containing one to four seeds.

The most important species to the farmer is the common red clover (Trifolium pratense), now naturalized in North America, but a native of Europe and northern Asia. It has been grown in England for over 300 years. It is a more or less hairy perennial, growing from six inches to two feet high. The flower-heads are dense, oval or ovoid, about one inch long; flowers sessile or nearly so, red, rarely white, remaining erect in fruit; calyx sparingly hairy. It is one of our best forage plants for nutritive value, high yield and good range of adaptability; it is commonly found in meadows and pastures and is used as a green manure. It flowers from April to November. The seed weighs about 60 pounds to the bushel, and, if sown alone, 10 to 12 pounds will sow an acre.

Zigzag clover, cow-grass and marl-grass or mammoth clover (Trifolium medium) may be an offshoot of T. pratense, from which it differs in being a larger plant, having zigzag stems, the flower-heads larger, longer stalked and often of a deeper purple color, with a practically smooth calyx tube. It is a native of Europe and Siberia and blooms during the

summer.