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CENTRALISATION-CENTRE OF GRAVITY.

ments.

which the European monarchs, such of them espe- | as parallel. But a system of parallel forces (see cially as became more powerful than their neigh- PARALLEL FORCES) has a single resultant acting bours, were ever striving; and a few of them, such through a fixed point, whose position is independeni as Charlemagne, and, long afterwards, Charles V., of the position in space of the points of application seemed to have almost restored it. In this country, of the component forces, provided their relative we trace C. from the time when there were about a positions in the system continue unchanged. This dozen kings in Britain, and perhaps as many in point is the C. of G. ; and if it be supported, it Ireland, till the united kingdom came under the is clear that the body will balance itself upon it in rule of one monarch. A subsidiary C. at the same all positions. The same reasoning obviously applies time made silent progress, absorbing the feudal to any system of bodies rigidly connected. It is power of the aristocracy and the municipal privileges usual to demonstrate this and the general rule for of the corporations. In other countries--as, for in- finding the C. of G. by proving it first in the case stance, in France, notwithstanding her desperate of two heavy particles forming a body or system, struggles for freedom, this process of C. has tended and then extending the proof to the case of any to a pure irresponsible despotism. With so sad a number of particles.

number of particles. Let P and Q (see fig. 1) be result before their eyes, a distrust of C. has not un- two heavy particles. Join P and Q, and divide the naturally been felt by some inhabitants of Great line PQ in c, so that weight of P : weight of Britai!. But the British constitution possesses a Q :: CQ : CP. Then C will be the C. of G. grand remedy, which turns the process to good of P and Q. Draw ACB horizontal, and PM, use instead of mischief. While administrative QN vertical, meeting

Q authority has been centralising in the crown, the AB in Mand N. controlling power of parliament has been increas. Then if P and Q

A M ing at a more rapid ratio, so that the vesting of a represent the weights

-B function in the crown or central government, means of P and Q, we have the putting it under the control of parliament, P:Q :: CQ : CP. and especially of the peoples' representatives in the But CQ : CP :: CN

P House of Commons. There is nothing done in any : CM by similar tri

Fig. 1. of the offices under the government for which a angles. Therefore secretary of state, or some other member of the P:Q:: CN : CM, and P.CM Q.CN. P and Q, ministry, may not at any time be called to account therefore, are balanced about C. See BALANCE and in parliament. The efficiency of this control was in LEVER. This is true in all positions of P and Q, for a manner proved by one or two instances in which no assumption was made as to their positions. C, offices with central powers were created, without therefore, is their centre of gravity. Also, we may being connected with any of the great state depart conceive P and Q to be removed (see PARALLEL

There were, for instance, the English Poor- FORCES), and in their stead a particle at C equal law Board, and the Board of Health. Both created to them taken together in weight. If, now, the much discontent and outcry about C., and it was system contained three, it is clear how we should found necessary to transfer their functions to the proceed to find its centre of gravity; having found great government departments, the heads of which the C. of G. of two, we should consider the system are immediately responsible to parliament. It is not as formed of two-viz., the equivalent of the first the policy of this country in any case to abolish two at their C. of G., and the third, when the local management, but rather to aid and direct it case would fall under that already treated; and : from the central authority. The constituents of so on, extending the rule to a system containing local bodies are often disinclined to watch or control any number of particles. Apart from this rule, them, and the business falls into the hands of incap- however, it is possible, in the case of most regular able or designing men, or is otherwise mismanaged. homogeneous bodies, to fix upon their centres of A very little central help—especially from a quarter gravity from general considerations. The C. of where the proceedings of other bodies of the same G. of a straight line, for instance, must clearlykind are known-remedies such defects. One of the be in its middle point. So the C. of G. of a methods in which the government has of late been uniform homogeneous cylinder must be in the in use to exercise its central power, has been by the middle point of its axis. It must be in the appointment of inspectors, who make reports which axis, for the cylinder clearly is equally balanced are laid before parliament. This is, in reality, about its axis. It must also be somewhere in its. nothing more than a method of concentrating public middle circular section, for it will balance itself on. opinion on the proceedings inspected and reported a knife-edge under that section. It must, therefore, on, and as such it is very efficacious.

be in a point where that section cuts the axis, CENTRE OF GRAVITY is that point in a or in the middle of the axis. The C. of G. of a body or system of bodies rigidly connected, upon uniform material plane triangle may be found from which the body or system acted upon only by the similar considerations. The triangle ABC (see force of gravity, will balance itself in all positions. fig. 2) may be supposed to be made up of uniform Though the action of gravity enters this definition, material lines parallel to its base AB; each of many of the properties of the point are independ- these will balance upon its middle point. The ent of that force, and might be enunciated and whole triangle, therefore, will balance upon the line proved without conceiving it to exist. By some, CD, which bisects the base AB and all lines accordingly, the point has been called the centre parallel to it. In of magnitude, and by others, the centre of parallel the same way, the forces. Such a point exists in every body and triangle will balance system, and only one such point. Every body may upon the line AE, be supposed to be made up of a multitude of minute bisecting BC. But particles connected by cohesion, and so far as its if a figure balances balance under gravity is concerned, each of these itself upon a line, its may be supposed to be removed, and its place occu-C. of G. must lié in A pied by a force proportioned to its weight. Instead that line. The C.

Fig. 2. of the body, on these suppositions, we should then j of G. of the triangle have a system of parallel forces, the lines from the is therefore in CD, and also in CB. It must there.. various particles to the earth's centre being regarded 'fore be at g where these lines intersect, ą being the

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CENTRE OF GYRATION-CENTRE OF PRESSURE.

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only point they have in common. Now, by geometry, | body which are nearest to the axis of suspension we know that g divides CD, so that cg=CĎ. would, as simple pendulums, vibrate more rapidly Hence the rule for finding the C. of G. of a triangle: than those more remote. Being connected, however, Draw a line from the vertex, bisecting the base, and as parts of the solid body, they vibrate all in the measure off Cg, two-thirds of the line. g is the same time. But this connection does not affect centre of gravity. By a similar method, the C. of G. their tendencies to vibrate as simple pendulums, and of a great number of figures may be determined. the motion of the body which they compose is a

The above method applies only where the figure of compromise of these tendencies of its particles, the body is regular, and its mass homogeneous. But Those nearest the axis are retarded by the more many bodies, besides being irregular, are formed by remote, while the more remote are urged on by the the agglomeration of particles of different specific nearer. Among these particles there is always one gravities. Of these, the C. of G. can be found only to be found in which the accelerating and retarding by experiment, though not always satisfactorily. effects of the rest are mutually neutralised, and Let the body be suspended by a string, and allowed which vibrates in the same time as it would if it to find its position of equilibrium. The equilibrium were unconnected with the other parts of the body, being due to the tension of the string counter- and simply connected by a fine thread to the axis balancing gravity, it follows that the tension is in of suspension. The point in the body occupied by the same line with that on which gravity acts on the this particle, is its centre of oscillation. By this body. But the tension acts on the line of the string, C. of 0. the calculations respecting the vibration of which therefore passes through the centre of gravity. a solid body are rendered as simple as those of a Mark its direction through the body. Suspending molecule of inconsiderable magnitude. All the it then by another point, we should ascertain a properties which belong to a single pendulum may second line in which lies the centre of gravity. be transferred to a vibrating body of any magnitude The C. of G., then, must be where these lines inter- and figure, by considering it as equivalent to a sect.--For the effect on the stability of bodies of the single particle of matter vibrating at its centre of position of the C. of G., see STABILITY.

oscillation. CE'NTRE OF GYRATION is the point at

The determination of the position of the C. of 0. of which, if the whole mass of a body rotating round a body usually requires the aid of the calculus. It is an axis or point of suspension were collected, a given always further from the axis of suspension than the force applied would produce the same 'angular centre of gravity is, and always in the line joining velocity as it would if applied at the same point to the centre of gravity and the point of suspension, the body itself. The C. of G. bears a strong analogy when the body is suspended from a point. The rule to the centre of oscillation. The cases differ only for finding it in such a case is: If s be the point of in this, that in the latter the operating forces are suspension, and 0 the C. of O., SO supposed to act at every point of the moving body,

M.Sg while in the former there is only one force acting it is the quotient obtained by dividing the moment upon one point. The C. of G. is found by the fol- of inertia of the body by the product of its mass into lowing rule: Divide the moment of inertia of the the distance of its centre of gravity from the point rotating mass by the mass of the body, and extract of suspension. the square root of the quotient. The result is the CENTRE OF PERCU'SSION. The C. of P. distance of the point from the axis of rotation. of a body or a system of bodies revolving about The moment of inertia, it may be stated, is the sun a point or axis, is that point in it, which striking of the products of the weight of each point of the an immovable object, the whole mass shall not mass by the square of the perpendicular distance of incline to either side, but rest, as it were, in that point from the axis.

equilibrio, without acting on the centre or axis of CE'NTRE OF MA'GNITUDE or FIGURE (see suspension. If the body be moving freely, then CENTRE OF GRAVITY). C. of M. is the point on which the C. of P. is that point in it at which its whole plane figures and curved surfaces would balance impetus is supposed to be concentrated. In this themselves, supposing their areas to have weight. case, if the body struck with its C. of P. an Thus, the centre of a circle is its centre of magnitude. immovable obstacle, and if it were perfectly rigid Otherwise, C. of M. or F. is a point so situated that and inelastic, it would come to perfect repose ; all straight lines passing through it, and terminated whereas, if it struck the obstacle with any other by the circumference or superficies of the figure or point, a rotatory motion would be produced in it. surface, are bisected in it.

When the body is moving freely, and there is no CE'NTRE OF OSCILLA'TION. Referring to rotatory motion, the C. of P. coincides with the the article PENDULUM, the reader will see that the centre of gravity. If the body be moving round a time of a pendulum's vibration increases with its point or axis of suspension, the C. of P. coincides length, being always proportioned to the square root with the centre of oscillation. The more compliof its length. This is strictly true only of the sim- cated case of a body rotating round an axis within ple pendulum, in which the pendulous body is sup- formulæ which cannot conveniently bé translated

it, would require, for its explanation, analytical posed to have no determinate magnitude, and to be connected with the point of suspension by an inflexi- which the axis may have in which there will be no

into ordinary language. There are many positions ble wire without weight. If, bowever, the vibrating c. of P.-i. e., there will be no direction in which body have a determinate magnitude, then the time of vibration will vary, not with the square root of its an impulse could be applied without producing a length, but with the square root of the distance from shock upon the axis. One case of this sort is that the

axis of suspension of a point in the body called of the axis being a principal axis through the centre its centre of oscillation.

of gravity. If each part of the vibrating body were separ

CENTRE OF PRE'SSURE. The C. of P. of ately connected with the axis of suspension by a any surface immersed in a fluid is the point in fine thread, and entirely disconnected from the rest which the resultant of the pressures of the fluid of the body, it would form an independent simple on the several points meets the surface. When the pendulum, and oscillate is such--the time of each bottom of a vessel containing fluid, or when a vibration being as the square root of the length of plane immersed in fluid, is horizontal, the pressure its thread. It follows that those particles of the on every point of it is the same, being that due

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CENTRIFUGAL AND CENTRIPETAL-CEPHALOPODA.

AND

to the weight of the column of fuid standing Asterolepis (star-scale), from the circular markings above the bottom or plane. In either case, the on its cephalic shield. pressures at the different points obviously form a

CEPHALO'NIA, or CEFALONIA, the largest system of equal parallel forces, whose centre will be the centre of gravity of the bottom or plane, their of the seven Ionian Islands (q. v.), is situated at the

entrance of the Gulf of Lepanio or Corinth, in resultant passing through this point being the sum of all their forces. But when the plane is inclined lat. 38° 3'—38° 30' N., and long. 20° 21'—20° 49' E. at any angle to the surface of the fluid, the pressure about 30 miles, and its total area 348 square

It is irregular in shape. Its greatest length is is not the same at all points, but is obviously greater miles. Its surface is mountainous, the soil

, for the at the lower than at the upper points, for the lower

The inhabihave to support taller columns of the fluid. The most part thin, and water very scarce. resultant of these forces, then, will not pass through tants, however, are industrious and enterprising, the centre of gravity of the surface, but through will grow, and currants and olive-oil are also a point below it. This point is the C. of P., and evidently will lie below the centre of gravity for all produced for export. The climate is warm and fluids in which the pressure increases with the agreeable. The population in 1858 amounted to

72,534. The nuinbers who are brought up to depth. If the surface pressed upon form part of the containing vessel, and be supposed movable, it the medical profession are remarkable; it is said will be kept at rest by a pressure equal to the sum has not a practitioner from Cephalonia.

that there is hardly a town in the Levant which

The of the fluid pressures applied at the C. of P., and livhabitants are also much more disposed to engage acting in the opposite direction. In the case of a vessel with a parallelogram for one side, the C. of in foreign trade than their brethren of Corfu or P. is at the distance of one-third of the height from Zante, and own more vessels. The island is subject

to frequent, but slight earthquakes. There is the bottom. In the case of a triangular vessel whose base is at the bottom, it is one-fourth of the height always a small English garrison kept at C., and

steamers ply weekly between it and Malta and only.

Greece (Patras). The language spoken is a Greek CENTRI'FUGAL

CENTRI PETAL

are dialect. The chief towns are Argostoli (q. v.) and terms used in Botany to designate two different Lixuri. kinds of inflorescence, or modes of flowering of C. is called by Homer Same or Samos, and during plants. When the flower-bud which terminates the heroic age was subject to Ulysses, whose resithe floral axis, and is central in the inflorescence, dence was in the neighbouring isle of Ithaca (q. 1.). is the first to expand-in which case the others are Later, C. appears under the name of Cephallenia. developed in succession from the centre outwards It successively fell into the hands of the Athenians, the inflorescence is said to be centrifugal. When Romans, Byzantines, and Venetians, from the last the outermost flowers expand first, the inflorescence of whom it was several times wrested by the Turks. is centripetal, as is the case in catkins, spikes, and on the ruin of the Venetian Republic in 1797, it racemes, in which the flowers nearest the base are

was seized by the French, who were in their turn the first to expand, and those nearest the apex the dislodged by the Russians. In 1809, it finally came last. These modes of inflorescence are very charac- into the possession of England. teristic of different plants, of genera, and of orders.

CENTRIFUGAL FORCE. See CENTRAL CEPHALO'PODA (Gr. head-footed), a class of FORCES.

mollusks, the highest in organisation of that division

of the animal kingdom. To this class belong the CENTRIPETAL FORCE. See CENTRAL

Nautili, Spirulæ, Argonauts, Poulpes, Squids or FORCES.

Calamaries, Cuttle-fish, &c., of the present time, CEPHAË'LIS.' See IPECACUANHA.

and the Ammonites, Belemnites, &c., of former CEPHALA'SPIS, a genus of fossil Ganoid fishes, geological periods. The C. are all marine, and only of which six species have been described, two a few of them are capable of leaving the water, and belonging to the Upper Silurian, and four to the moving about in search of food on the shore. Devonian measures. The head was protected by The C. receive their name from having organs of a large ganoid plate, sculptured externally with prehension and locomotion attached to the head, circular radiating markings. Agassiz gave the name an arrangement towards which a gradual approach C. (buckler-headed) from this extraordinary cover- may be traced in the highest gasteropod (q. v.) ing, which has very much the appearance of, and mollusks. These organs have been variously desigwas formerly supposed to be, the cephalic shield of nated arms, fect, and tentacula. They have no true an Asaphus. The body was covered with rhom- homology' with the limbs of vertebrate animals, boidal enamelled scales, and furnished with dorsal but are only analogous to them in respect of the and pectoral fins : it terminated in a large hevero- purposes which they serve.—The body of the C. is cercal tail. In a graphic description of this fossil in a bag, formed of the mantle (see MOLLUSCA), open his Old Red Sand stone, Miller thus sketches the only at the end to which the head is attached. In general appearance of the animal: “Has the reader some, this bag is almost spherical, and locomotion ever seen a saddler's cutting-knife-a tool with a is accomplished only by the appendages of the crescent-shaped blade, and the handle fixed trans- head; in others, the body is elongated, and furversely in the centre of its concave side ? In general nished with two fin-like expansions, which are the outline, the C. resembled this tool; the crescent- principal instruments of locomotion. In locomoshaped blade representing the head, the transverse tion by the fins, a cephalopod swims like a fish, handle the body.' The endo-skeleton was carti- with the head first, and often very rapidly; in laginous, retaining the notochord through life. The locomotion by the arms, it drags itself along, laying flexible body, assisted by the large tail and the fins, hold of any object within reach by means of suckers, would give the C. the power of moving rapidly, with which the arms are furnished. Some C. are through the water. Being a predaceous fish, it must capable also of moving backwards through the have been a formidable enemy to its associates in water by alternate contractions and expansions of the Palæozoic seas, for, besides its power of rapid a muscular web which unites the bases of the motion, the sharp margin of its shield probably arms; some appear to depend for a similar power did the work of a vigorously hurled javelin, as in of swimming backwards upon the forcible ejection the sword-fish. This genus was originally named of water from the cavity which contains the gills.

CEPHALOPODA,

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The head of a cephalopod is roundish, generally, the Dibranchiata they are only eight or ten in furnished with two large and prominent eyes, very number, furnished with suckers (acetabula); two of similar in structure to those of vertebrate animals. them, when they are ten in number, being much There are also ears, but they consist merely of little longer than the rest, and differing from them in cavities, one on each side of the brain, in each of form. The suckers are very admirably constructed which is suspended a membranous sac containing a -an adhesive disk of muscular membrane, often small stone. The organs of smell are not very having a cartilaginous circlet, capable of most certainly known, but it appears that the C. possesses exact application to any this sense, as well as that of taste, of which the object, with an aperture in character of the tongue is much more indicative the centre leading into a than in many vertebrate animals.-The brain forms cavity, the bottom of which a ring around the gullet. The whole nervous system can be retracted like a piston

so as to form a vacuum,
and render the adhesion of
the sucker close and firm,
whilst
the muscular

B
action being interrupted or
reversed, it immediately lets
go its hold. The poulpe has
each of its eight flexible
arms crowded with 120 pair
of such suckers, and as an
animal of this kind exists on
some tropical shores, with

A
arms about two feet long, it
is not wonderful that it is
reckoned dangerous.

Still Cephalopoda, suckers of: more formidable, however, A, a single sucker, side view: are the Hook-squids of the B, a portion of one of the South Seas, the two long suckers, front view; a,

tentacula, arms of which have suckers cartilaginous circlet; 6, furnished in the centre with central cavity; c. piston, a hook to enter into the d, section of the tentacle. flesh of any creature of which they may lay hold, and so more effectually to secure their prey. .

The sexes are distinct in all the cephalopoda.

The eggs have a horny covering, and after their Cephalopoda Loligopsis.

extrusion from the parent, become agglutinated into

masses of various forins. The young, from the first, is more complex than in the lower mollusks. The very much resemble the mature animals except in mouth opens in the midst of the circle of arms. It size. is furnished with a strong horny beak of two All the Dibranchiata are provided with a peculiar mandibles, moving vertically, not unlike the bill of organ of defence, called an 'ink-bag,' which is want. a parrot, but the upper mandible the shorter of the ing in the Tetrabranchiata. This ink-bag is filled two.—The digestive apparatus is very complicated. with a peculiar secretion, capable of being expelled The gullet swells out into a crop, and there is a at will io darken the water, and facilitate the escape gizzard as muscular as that of a bird. The intes of the cephalopod. tine, after a few convolutions, terminates in the

The Tetrabranchiate C. have a chambered shell. cavity which contains the gills, at the base of the See NAUTILUS. The Dibranchiate c. have 110 funel by which the water is ejected after having external shell--the shell of the female Argonaut supplied air for respiration. This cavity is situated (q. 1.) being scarcely an exception-but they have within the mantle or bag, and separated from the an internal shell (cuttle-fish bone, &c.), sometimes other viscera by a membranous partition. Into it merely rudimentary, included between two folds of the water is freely admitted by means of a slit the mantle, and apparently intended to give support or valvular opening, being drawn in by muscular to the soft body of the animal., action, and again expelled with considerable force The C. are all very voracious, feeding on fish, through the funnel, which opens at the neck, and mollusks, crustaceans, &c. Even a powerful crab with its current all secretions, eggs, and excrements is not safe from the attacks of a Dibranchiate are carried forth. There are only two gills in the cephalopod little bigger than itself; the armis, so greater number of existing C., the only exceptions abundantly provided with suckers, seize it, and being the two or three known species of Nautilus, trammel erery movement, whilst the parrot-like beak which have four gills; and two-gilled C.--the order is strong enongh to break the hard shell. Cuttle-fish Dibranchiata--are in many respects of higher and squids are often very troublesome to fishermen, organisation than the four-gilled--the order Tetra- following shoals of fish, and devouring great numbers branchiata--which, although containing so few of them after they are entangled in the net. recent, contains a vast number of fossil species. Fossil C. exist in all the strata which form the Each gill consists of many membranous plates, earth's crust. The order Tetrabranchiata is almost fixed to two sides of a stalk.-The heart in the exclusively a fossil order, being represented by Tetrabranchiata consists of a single ventricle only; not more than four recent species. With the but besides this systemic heart, the Dibranchiata exception of two genera, Nautilus and Aturia, this have two branchial or respiratory hearts, contractile order is confined to primary and secondary rocks. reservoirs, one for each gill, by which the blood is The two groups into which it is divided are also forced into these organs.

characteristic of geological epochs. The NautiThe “arms' or 'feet' are very numerous in the lide, with simple or gently undulating septa, and Tetrabranchiata, not provided with suckers, but siphuncle central or in the inner margin, belong, hollow, and with long retractile tentacula; in with the exception of the two genera just referred

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CEPHALOPTERA-CERBERUS.

RULA, &c.

to, to the Palæozoic rocks. Including a small group, CERAMIA CEÆ, a sub-order of Algæ (q. v.), also which, while it has the siphon on the external called FLORIDEÆ, and consisting of sea-weeds of a margin, has yet simple septa, the Nautilidæ are rose or purplish colour, with fronds formed of cells represented by 145 Silurian, 158 Devonian, and 91 arranged in rows, sometimes in a single row; the Carboniferous species. The Ammonitido have the sporocarps containing cells or spores, often in fours siphuncle always on the outer margin of the shell, (tetraspores), with a transparent perispore, and and the septa with corrugated or lobed margins. enclosed iu receptacles of very various form and This group, with the exception of Goniatites, a structure. They are most abundant in the seas of Palæozoic genus, is peculiar to, and co-extensive the northern temperate zone. Many of them are with, the secondary strata. Of the 930 species that very delicate and beautiful. A considerable number have been described, more than the half belong to furnish agreeable articles of food of a gelatinous the genus Ammonites (q. v.).

Dature, as Dulse (q. v.), CARRAGEEN (q. v.), or Irish The order Dibranchiata is found first in the Lias, Moss, and certain species of PLOCARIA (q. v.), which and extends through the more recerit strata, receiv- are much used on the sea-coasts of the East Indies. ing its full development in our present seas. Scarcely | The edible swallows' nests of the East are supposed 90 fossil species have been described, while more

to be formed of a sea-weed of this sub-order, a spethan double that number are known as recent cies of Gelidium. animals. See AMMONITES, ARGONAUT, BELEMNITES,

CERAMIC (Gr. keramos, potter's clay, from kaio, CALAMARY, CUTTLE-FISH, GONIATITES, HAMITES, to burn, and era, earth), a term used to designate HOOK-SQUID, Nautilus, ORTHOCERAS, Poulpe, Spi- the department of plastic art which comprises all

objects made of clay, such as vases, cups, bassiCEPHALOʻPTERA (Gr. head-wing), a genus of rilievi, cornices, and the like. cartilaginous fishes of the ray family, the type of a sub-family, Cephalopterido. The pectoral fins are

CERA'STES, or HORNED VIPER, a genus of very much elongated, so as to give great breadth to serpents of the family Viperidæ, distinguished by a the fish. The tail is slender and without fin, but broad depressed heart-shaped head, the scales of armed near its origin with a great spine. The head which are similar to those of the back, and paris terminated in front by a straight line, and on ticularly remarkable for the development of one of each side of it there projects a membrane (prece- the scales of each eyelid into a spine or born, phalic fin) rolled upon itself, and resembling in often of considerable length. The tail is very shape a pointed horn. The name DEVIL FISH has been given to these creatures in America, of which but one species, C. vampirus, has been observed on the coast of the Southern States. The C. giorna occurs in the Mediterranean, and there acquires a great size: one is mentioned as having been taken off Messina, which weighed 1250 lbs.--more than half a ton. But this is small in comparison with the size of some of the Cephalopteride which occur in tropical seas : one taken at Barbadoes required seven yoke of oxen to draw it. They are very dangerous to swimmers and bathers.

Horned Viper (Cerastes vulgaris). CE'PHEUS, a constellation of the northern hemisphere, containing, according to the Britannic cata. distinct from the body. This genus is exclusively logue, 35 stars. Its principal star is Alderamin, of the third magnitude.

African, and very venomous.

The best known

species, C. vulgaris, the Horned Viper of the north CEPO'LA. See BANDFISH.

of Africa, was called C. by the ancients, the name CERAʼM, a long and narrow island of the Asiatic being derived from the Greek keras, a horn. Archipelago, running nearly 200 miles in the parallel was correctly described by the traveller Bruce, but of about 3° S., long. 128-131° E., between Booro his description was for some time regarded with on the W., and Papua or New Guinea on the E. incredulity. Other species of the same genus are C. With an area of nearly 6000 square miles, it has nasicornis of the western coast of Africa, and C. about 27,000 inhabitants. From east to west it is caudalis of the Cape of Good Hope. traversed by mountains rising at some points 8000

CE'RATE (Lat. cera, wax), a compound of wax feet above the sea. While the high grounds yield with other oily and medicinal substances in such abundance of fine timber, the valleys are fertile in proportions as to have the consistence of an Ointtropical productions. The natives, chiefly negroes ment.(q. v.). Simple C. is made by melting together of the Papuan type, excel in the manufacture of equal parts of white wax and olive oil; they are to

The Dutch claim the sovereignty, and bold be heated together, and carefully stirred into a uviseveral establishments on the coast.

form substance while cooling. CERA'MBYX, a Linnæan genus of coleopterous insects, included among those which, on account of

CEPRATITES, a genus of Ammonitidæ, peculiar

They are disthe length of their antennæ, are usually kuown as to, and characteristic of, the Trias. LONG-HORNED BEETLES, and now generally regarded tinguished from the other members of the family by as the type of a tribe or family. To this tribe having the lobes of the sutures serrated, while the inbelongs the Musk Beetle of England (Callichroma tervening curves, directed towards the aperture, are moschata), remarkable for its strong and agreeable simple

. Twenty-six species have been described. odour, which, however, is rather that of roses than CERBERUS (Gr. kerberos,) in Greek mythoof musk. Some foreign species have the odour of logy, was the name of the many-headed dog--the musk in great perfection. C. heros, one of the offspring (according to Hesiod) of Typhon and largest European beetles, extremely rare in Britain, Echidna--who guarded the portal of the infernal deposits its eggs in a hole which it excavates for regions. Later writers describe C. as only threethat purpose in the wood of the oak; and the grub headed, with the tail and mane composed of feeds upon the wood, excavating long passages serpents, though the poets sometimes encumber him through it.

with a hundred heads.--A northern constellation,

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