The atomicity of an element can only be determined from its compounds with monads, or with monatomic groups.

An important point in the theory of atomicity is that, with one or two exceptions, no molecules exist containing an atom having a single atomicity unoccupied. Such a group (which is said to be unevenly unsaturated), on being set at liberty, at once combines with a neighbour of its own kind, and forms a double group. It is supposed to be for this reason that the molecules of hydrogen, chlorine, and bromine each contain two atoms

Constitution.We have said that the nature of a compound depends upon the number and kind of atoms composing it, and also upon the manner in which the atoms are arranged or grouped. The last is an important point, for we very frequently find (more especially in the case of the compounds of carbon) that the molecules of two or more bodies contain the same number and kind of atoms, and yet possess very different properties. Thus acetic aldehyde and oxide of ethylene both have the formula C2H4O. The difference between such bodies can only be explained by assuming that the atoms composing their molecules are differently grouped; in other words, that they have a different constitution. The investigation of the constitution of compounds forms one of the principal aims of modern C., and has already advanced considerably. Substances which, like aldehyde and oxide of ethylene, have a similar atomic composition but a different constitution, are said to be isomeric (see ISOMERISM). Substances the molecular weights of which are multiples of one another, are said to be polymeric. Thus acetylene, C, H,, and benzol, C6H6, are polymers. The theory of atomicity has lead to the introduction of graphic formula for representing the arrangement of the atoms in a molecule. Subjoined are the graphic formulæ of the two isomeric substances we have mentioned to illustrate the manner in which the difference in their constitution is accounted for by the theory of atomicity.

Chemists and Druggists, Laws Relating to. The Pharmaceutical Society of Great Britain was incorporated by royal charter on 18th February 1843. The charter provides that the society shall have the right to examine candidates for admission, and to confer on those qualified the title of Pharmaceutical Chemist.' To assume the title without licence is punishable by fine; but the practice of a chemist and druggist is open to all. The Council of the Society is required to appoint examiners for Scotland, who have the same powers as the examiners in England. No member of the medical profession, or who is practising under the right of a degree of any university, or diploma or licence of a medical body, is entitled to be registered; and if any one who is registered become a member of the medical profession, he is disqualified from remaining on the register. See APOTHE

CARY.

Chem'nitz, the first manufacturing and second trading town of Saxony, on a river of the same name, in a wide valley, at the foot of the Erzgebirge, 36 miles S.W. of Dresden by railway. It has 80 cotton and spinning mills, 450 machines and 3000 handlooms, 50 machine-works, supplying locomotive and other engines to all parts of Europe, over 50 large dyeworks, besides manufactures of silk, gloves, lace, musical instruments, embroideries, &c. In 1874 the export of woollen, cotton, and other manufactured goods to America alone amounted to £420,776. There are various technical schools, several good public buildings, an exchange, a large theatre, and fine promenades formed on the site of the old walls. Pop. (1871) 68,229. The first Christian church was built here in 938 by Otto I., and C. became an imperial city under Rudolf of Hapsburg in the 13th c. It was ruined by the Thirty Years' War, and only began to prosper again on the introduction of cotton-weaving in the end of the 17th c.

Chem'nitz, Martin, one of the most distinguished theologians of the Lutheran Church in the 16th c., was born at Treuenbrietzen, in Brandenburg, 9th November 1522, and studied under Melancthon at Wittenberg. In 1547 he was appointed rector of the cathedral school at Königsberg, where he engaged in a controversy with Osiander in defence of the Lutheran doctrine of justification. Returning to Wittenberg in 1553, he lectured on Melancthon's Loci Communes-the origin of his own Loci Theologici, reckoned the best book of systematic theology produced in that age. In 1554 he settled in Brunswick, where he first became pastor, then superintendent, and died 8th April 1586. He is most distinguished for his treatises against the Jesuits (Theologia Jesuitarum præcipua capita, Leips. 1562) and the Decrees of the Council of Trent (Examen Concilii Tridentini,

114

4 vols. Leips. 1565); but probably the greatest ecclesiasticopolitical work of his life was inducing the Churches of Saxony, Franconia, and Swabia, to adopt the Concordienformel as their confession of faith.-Martin C., son of the preceding (born 1561, died 1627), became privy councillor and chancellor to the Duke of Holstein-Gottorp.-Philipp Bogislav von C., son of the younger Martin (born 1605, died 1678), entered the service of Sweden, was made royal historiographer, and raised to the order of nobility.

Chemnitzia, a genus of Gasteropodous mollusca, the shell of which is of slender, elongated shape the aperture being oval and the operculum horny. This genus is included in the family Pyramidellida, and its fossil representatives first appear in the Permian rocks, more than 150 fossil species being known.

Chenab', the largest of the rivers from which the Punjab ('five rivers') takes its name. Its source is in the Paralasa range of the Himalayas. After a course of about 600 miles it receives the Jhelum on its right; somewhat lower down, the Ravee on its left; and 110 miles still lower, on the same side, the united stream of the Beas and Sutlej. The entire body of waters before joining the Indus bears the name of the Punjnud. At Waizerabad the railway crosses C. by one of the longest iron bridges in the world, having a length of 1 miles, and consisting of 64 spans of 1426 feet each. This bridge was opened by the Prince of Wales, 22d January 1876.

Chén'ier, André-Marie de, a French poet and political writer, was born October 29, 1763, at Constantinople, where his father was consul-general for France. He came to France at He came to France at an early age, and studied at the Collége de Navarre, in Paris, there evincing poetic talent and acquiring a passion for ancient literature. In 1784 he travelled on account of his health in Switzerland, Italy, and Greece, and in 1787 he visited England as secretary to the embassy of M. Luzerne. Returning to Paris in 1790, while the Revolution was raging, he joined the brilliant Society of '89,' and volunteered to assist the infirm Malesherbes in the defence of Louis XVI. C. stood as far apart from despotism as from anarchy, and in prose and verse proclaimed at once his love of liberty and his detestation of violence. He was at last brought before the Revolutionary Tribunal, was condemned, along with forty-five others, and was guillotined, July 25, 1794. When in prison C. burst forth in a beautiful ode. La Feune Captive, of which the subject was his fellow-prisoner, the celebrated Comtesse de Coigny. His Elégies are exquisite in their mingling of classical spirit with an original boldness and vivacity. Only a tithe of his projected poems were finished, still the influence of C. is clearly visible in the early works of Chateaubriand, Barthelémy, Lamartine, and Victor Hugo. Of the many editions of his Poésies, the best are those of Delatouche (Par. 1840), and Becq de Fougières (1862); and of his Œuvres en Prose, there is a selection by Hugo (1840).-Marie-Joseph de C., brother of the former, was born at Constantinople, August 28, 1764, and became famous as the principal dramatist of the Revolution, and as a member of the Legislative Assembly from 1792 to 1802. He is also the author of the Chant du Départ and other songs. His dramas, of which the chief are Charles IX. (1790), Jean Calas (1792), Henri VIII. (1793), and Timoléon (1795), are full of republican declamation, and of the wild sentiments of the time. C. died January 10, 1811. His Euvres Complètes were published in 8 vols., with a memoir by Daunou (1823-26).

Chenopodia'ces, the Goosefoot or Spinach order, a natural order of Dicotyledonous plants, herbs, or small shrubs very generally distributed over the world, but chiefly found in temperate or ex-tropical countries. There are about 500 species, and among the best-known of the seventy-four genera are Salicornia, Atriplex, Beta, Chenopodium, and Salsola. From the ashes of several species-Salsola, Salicornia, &c.-which grow in salt marshes, barilla, used for obtaining carbonate of soda in former times, is obtained; but on account of soda being now much more easily obtained from other sources, the demand has of late fallen off. Among the other species are beet and mangoldwurzel (see BETA), spinach, &c. The seeds of several of them contain volatile oil or are nutritive-e.g., Quinoa (q. v.). Some are anthelmintic, antispasmodic, aromatic, carminative, and stimThe fruit of the strawberry Blite (Blitum capitatum and B. virgatum) of the S. of Europe has a sweetish, insipid taste.

ulant.

Chenopodium, a genus of Chenopodiaceæ (q. v.), some of the British species of which are weeds, known under the name of Goosefoot. C. ambrosioides, the Mexican tea, is, owing to the essential oil which it contains, tonic and antispasmodic. C. anthelminticum yields 'wormwood oil,' so popular in the United States as a vermifuge. C. Quinoa, of the Pacific slopes of the Andes, is remarkable in so far that its seeds are extensively used as food by being ground and eaten as a gruel after the preparation has been seasoned with Chili pepper and other condiments, or by the seeds being roasted and boiled in water, which, after being seasoned, is supped. This last mixture, called carapulque, is a favourite Peruvian dish, and though unpalatable to those unaccustomed to it, is said to be very nutritious. The young leaves and shoots of the Good Henry, wild spinage, or Thesavy (C. Bonus-Henricus), a common British wayside weed, are, as well as those of C. intermedium, C. album, used as substitutes for spinach. The stinking goosefoot (C. olidum) is an antispasmodic and emmenagogue. C. Botrys, the 'Jerusalem oak,' of the S. of Europe, is expectorant and anthelmintic.

of Monmouthshire, on the Wye, is a station on the S. Wales Chep'stow (Old Eng. Ceapstow, 'a place of trade'), a town and Union Railway, 17 miles E. by N. of Newport, and has a river and coast trade in coal, iron, millstones, bark, cider, &c. bridge, and is exposed to some danger from the tide, which freIt lies in a rocky gorge, where the river is crossed by a fine quently rises to the height of 50 feet, and even higher. Pop. (1871) 3347. About 5 miles off are the ruins of Tintern Abbey.

Cheque is a draft or order on a banker. It is subject to a stamp-duty of one penny, adhesive or impressed. A C. must be payable on demand to the bearer, and be drawn on a banker under fifteen miles of the place of issue. A crossed C. has the name of a banker written across the face of it, to whom for security it is payable, or it may be crossed simply & Co.' leaving the holder to insert the name of the banker. In this case it is only paid through that banker. If presented by any other person, it is not paid without inquiry. By statute the crossing is to be held a material part of the C. Any one obliterating or altering a C., with intent to defraud, is guilty of felony. A banker is personally liable if he pay a C. to which the signature of the drawer is forged; but if the signature of the payee only be forged, and that of the drawer genuine, the bank or banker is not liable to the drawer. In Smith v. The Union Bank of London, it has recently been decided that a banker paying a C. to a party other than the bank whose name was written across, was entitled to do so. This decision has caused surprise and dissatisfaction in commercial circles, and will probably occasion further legislation.

Cher, one of the most central departments of France, in the basin of the Loire, has an area of 2800 sq. miles, and a pop. (1872) of 335,392. It is in great part an unbroken plain, bounded on the E. by the Loire, and intersected by the C. and Sauldre with their affluents, forming fertile valleys, in which are cultivated cereals, hemp, and vines, There are many fine forests, as those of Vierzon, Soudrain, Bornac, Choeurs, &c., and in the S. E., where rises a low range of hills, there occur extensive marshes. The climate is cold but healthy. Among the chief industries are cattle-rearing and iron-mining, while there are also extensive manufactures of cloth, porcelain, lace, glass, leather, &c., and a large export trade in agricultural produce, iron, and timber. C. is traversed by several canals, and by the Orleans and Lyons Railway. The capital is Bourges. department was chiefly formed out of the provinces of HauteBerri and the Bourbonnais.-The river C. rises in Creuse, near Crocq, flows N.W. through the department to which it gives name, and waters Loire-et-Cher and Indre-et-Loire, entering the Loire below Tours after a course of over 200 miles.

The

Cheras'co, a fortified town in the province of Turin, N. Italy, at the confluence of the Tanaro and Stura, 30 miles S. E. of The beautiful church Turin, has some wine and silk industries.

of Madonna del Popolo, with a remarkable sanctuary, is much visited by foreigners. The town was taken by the French, April 28, 1796, and three days later the armistice of C. was concluded here, by which the troops of France were allowed free passage through the states of Sardinia. Pop. 10,000.

Cherbourg, a strongly fortified seaport, and the most important town in the department of Manche, France, near the mouth

of the Divette, 16 miles E.S.E. of Cape la Hogue, and 214 W.N.W. of Paris, with which it is connected by railway. It is one of the first arsenals of France, and the chief station of the marines. The town has a church of the 15th c., an hospital founded by Napoleon, a valuable fine-art collection, and a library of 61,000 volumes. The extensive fortifications of C. were begun by Vauban, and were only completed in 1858, at the enormous cost of £8,000,000. To the N. the roadstead is commanded by a detached breakwater, which is nearly parallel to the shore, is 2 miles long, encloses an area of 2000 acres, and supports six strong batteries. Round each end of this breakwater or digue vessels enter the harbour, and these channels are further protected by a series of island and mainland redoubts. The two main strongholds of C. are the extensive Roches des Flamands and Roches du Homet, and the town itself is overlooked by two forts, placed on the heights of Roule. The defences of C. make up a total of thirty forts of all kinds. The military port includes an outer harbour, having an area of 18 acres, and a floating dock of 15, and an inner floating dock of 21 acres, together admitting forty vessels of the first rank. There are also extensive shipbuilding slips and graving-docks. At the mouth of the Divette is the commercial harbour, connected with the sea by a channel 2270 feet in length, and protected by a granite mole. Besides the naval industries, there are manufactures of lace, hoisery, chemicals, leather, &c., and an export trade chiefly in cattle, salt, and wine. Pop. (1872) 46,000, exclusive of the garrison and naval force. C., under the name Carusburg, is first authentically known in the 11th c., when a certain Comte Gerbert de C. appears in | the ranks of the Normans at Hastings. In 1418 it was taken by the English, in 1450 retaken by Charles VII., and in 1758 again captured by the English, who destroyed its defences. grand fête was given at C. on the opening of the inner floating dock by Napoleon III., at which the Queen of England and court were present by invitation, August 1858.

A

Cher'ibon, or Sheribon, the capital of a Dutch residency of the same name, in Java, on the N. coast of the island, has a trade in teak-wood, coffee, and indigo. Pop. of town, 12,000, of residency, 550,000.

Cherimoy'er (Anona Cherimolia), a delicious Peruvian and Brazilian species of custard-apple, now naturalised in the E. Indies and other tropical countries, and reckoned inferior only to the mangosteen. It belongs to the order Anonacea. See CUSTARD-APPLE.

Cherkask'. See TCHERKASK.

Cherry (Cerasus), a genus of shrubs or trees belonging to the natural order Rosacea. It might be regarded as a sub-genus of Prunus or Plum (q. v.). There are many species scattered all over the temperate portions of the world, C. avium (the gean), and C. vulgaris, both natives of Britain (though according to some the latter is a native of Syria and Western Asia generally, and only naturalised in Europe), and believed to be the progenitor of all the varieties of cultivated cherries. Their wood is highly valued by cabinetmakers and musical instrument makers. From the fruits of C. avium a spirit called Kirschwasser (q. v., and also Maraschino) is distilled in Germany, and the fruits are also extensively used in France, Germany, and Scandinavia for making soups. Among the other species are C. Padus, the Bird Cherry (q. v.) or hogberry, C. Mahaleb, of the middle and S. of Europe, C. Virginiana of America, C. Capollim of Mexico, C. caprecida of Natal, C. occidentalis, C. Lusitanica, and C. Laurocerasus, the Cherry Laurel (q. v.), both of which have evergreen leaves, &c. The wood of most of them is valued. Some have Some have astringent bark, also esteemed as a febrifuge, while the leaves and kernels of nearly all contain hydrocyanic (Prussic) acid. There are very many cultivated varieties of C. esteemed for their fruit and the liqueurs prepared from it. In addition to Maraschino and Kirschwasser, the Ratafia of Grenoble is prepared from pounded cherries to which brandy, spices, and sugar are added. A gum not unlike gum-arabic exudes from the bark of many species of the genus.

Cherry Laurel, Common Laurel, Bay Laurel, Laurel Cherry, or Laurel Bay, a name which should properly be limited to P. Laurocerasus, but which is often vaguely applied to the species of Cerasus which have evergreen leaves. From the amount of hydrocyanic acid contained in it, nearly every

part of the shrub is poisonous. The vapour of the bruised leaves will kill small insects. Hence, though custards, &c., are sometimes flavoured with C. L. water, great care should be exercised in its use.

Cher'so, an Austrian island in the Adriatic, government of Trieste, 12 miles S.S. W. of Fiume area 105 sq. miles; pop. 7590. The surface is rugged, and towards the N. there are forests. There is a town of the same name on the W. coast, with a pop. of 3500.

Chers'on. See KHERSON.

Chersone'sus, a Greek word denoting literally a land-island, i.e., a peninsula. Pausanius applies it even to an island united to the mainland by a bridge. Several places were so named by the ancients :—the Tauric C. (the Crimea), the Thracian C. (the peninsula of Gallipoli), the Cimbric C. (Jutland), and the Golden C. (Farther India or Malacca).

Chert'sey (Old Eng. Ceortes-ig, 'Ceort's Island,' so called because situated on a spit of land between the Thames and a brook), a town in Surrey, 21 miles S.W. of London by railway, on the right bank of the Thames, which is here crossed by a handsome bridge. It has several almshouses, one founded by Cowley the poet, who died here, and a school founded in 1725 by Sir William Perkins for clothing and educating fifty children. The principal trade is in malt, flour, tiles, and bricks, and vegetables for the London market. C. is a very old place. Bede (Hist. Eccl. lib. iv. cap. 6) says that Earconwald, Bishop of the E. Saxons in London, built a monastery here (circa 666 A.D.), but the town plays no part in history. Pop. (1871) 3146. of the Hebrews was a creature of composite form, variously Cher'ub (pl. Cherubs, Heb. Cherubim), in the theology described in the sacred books. It is represented as having the human form (Ezek. i. 5), hands (Gen. iii. 24), two wings and one face (Exod. xxv. 20), four wings, four faces—of a man, a lion, an ox, and an eagle-four hands, the soles of the feet like a calf's, and the whole body full of eyes (Ezek. i.). The four beasts of the Apocalypse (iv. 6-8) had six wings, and each a different form-of a lion, a calf, (the face of) a man, and an eagle. The attributes thus assigned to cherubs indicate the power of looking and moving swiftly in any direction without turning. As to the idea attached to the cherubs, everything points to this, that their proper task was to guard the unapproachable. The parallel to them is found in the winged bulls and lions of Nineveh (from which, it has been conjectured, they were borrowed, as recent discoveries show a strikingly close connection between Hebrew and Babylonian theology), the sphinx of Egypt, the chimæra, and griffin. Now the part ascribed to the griffin (Gr. gryps, the same word as the Heb. C.) is that of guardian of treasure, and that this was just the office of the C. is manifest from Gen. iii. 24, and Ezek. xxviii. 13-16: hence their post on the top of the Ark (q. v.), and over it in Solomon's temple (1 Kings viii. 6-7), and their multitude of eyes (Ezek. i. and Rev. iv. 6). See Kuenen's Religion of Israel (Eng. transl. 1875).

Cherubi'ni, Maria Luigi Carlo Zenobio Salvatore, the last of the great Italian composers, was born 8th September 1760 at Florence. He was educated in Italy, but went to Paris as a young man, and remained there, where he was unboundedly popular, for the rest of his life. Of his very numerous compositions, which include twenty-eight operas, eighteen masses, and numerous smaller works, a few overtures are still heard, and at least two operas, least two operas, 'Medea' and 'Les Deux Journées.' C. was Director of the Paris Conservatoire, where Auber and Boildieu were his pupils. He died in Paris, 15th March 1842. Piechianti, Notizie sulla Vita e sulle Opere di C. (Mil. 1843).

See

Cherus'ci, a German tribe, separated from the Suevi by the Silva Bacenis, or Harz Forest, which formed the southern Under their chief Arminius (Hermann), they totally boundary. routed the Romans, commanded by Varus, in the Teutoburg Forest, A.D. 9. Germanicus failed in his attempt to wipe out this stain on the Roman arms, but weakened by internal dissensions, the C. were subdued by the Chatti. About the beginning of the 4th c. they appear among the Frankish confederacy against Constantine, and, still later, Claudian alludes to them in his panegyric on the fourth consulship of Honorius.