pears to be prevented by the process of vegetation. | some substance which has a strong affinity for oxyGrowing plants purify the air by withdrawing car- gen. This condition is fulfilled by igniting chalk, or bonic acid, and yielding an equal volume of pure any of the carbonates, with half its weight of iron oxygen in return; but whether a full compensation filings, or of charcoal. The carbonate is reduced to for the deterioration of the air by respiration is pro- its caustic state, and the carbonic acid is converted duced in this way, has not as yet been satisfactorily into carbonic oxide by yielding oxygen to the iron or determined. the charcoal. When the first is used, an oxide of iron is the product; when charcoal is employed, the charcoal itself is converted into carbonic oxide. CARBONIC ACID. See CArbon. CARBONIC OXIDE. See CARBON. Carbonic acid abounds in mineral springs, such as those of Tunbridge, Carlsbad, and Saratoga. In combination with lime, it forms extensive masses of rock, which occur in all countries, and in every formation. It unites with alkaline substances, and the salts so produced are called carbonates. Its acid properties are feeble, so that it is unable to neutralize completely the alkaline properties of potash, soda, and lithia. For the same reason all the carbonates, without exception, are decomposed by the muriatic and all the stronger acids; the carbonic acid is displaced, and escapes in the form of gas. CARBUNCLE, in Surgery; a roundish, hard, livid, and painful tumour, quickly tending to mortification, and (when it is malignant) connected with extreme debility of the constitution. When this complaint is symptomatic of the plague, a pestilential bubo usually attends it. (See PLAGUE.) The carbuncle is seated deeply, in parts provided with cellular membrane, and therefore does not soon discover its whole dimensions, nor the ill digested matter it contains. CARCASS (in French, carcasse), in military language; an iron case filled with combustible materials, which is discharged from a mortar, like a bomb. There were formerly two kinds, oblong and round ones, but they are now out of use. In architecture, carcass signifies the timber-work of a house, before it is either lathed or plastered. CARCINOMA. See CANCER. CARDIACUS PLEXUS, in Anatomy, is formed by the nerves which supply the heart, and which are derived from the superior and inferior cervical, and first dorsal ganglia of the great sympathetic nerve from the par vagum and the recurrent nerve. Another gaseous compound of carbon with oxygen, called carbonic oxide, exists, or may be obtained by heating powdered chalk, or any carbonate which can bear a red heat without decomposition, with iron filings in a gun-barrel. It is evolved together with carbonic acid gas, from which it may be freed by agitating the mixed gases with lime-water, when the carbonic acid is absorbed, and the gas in question is left in a state of purity. It is colourless and insipid. Lime-water does not absorb it, nor is its transparency affected by it. When a lighted taper is introduced into a jar of carbonic oxide, it takes fire, and burns calmly at its surface with a lambent, blue flame. It is incapable of supporting respiration. A mixture of 100 measures of carbonic oxide, and rather more than 50 of oxygen, on being exploded in Volta's eudiometer by electricity, disappear, and 100 measures of carbonic acid gas occupy their place; from which the exact composition of carbonic oxide is easily deduced: for carbonic acid contains its own bulk of oxygen; and, since 100 measures of CARDING; a preparation of wool, cotton, hair, or carbonic oxide, with 50 of oxygen, form 100 mea-flax, by passing it between the iron points, or teeth, sures of carbonic acid, it follows that 100 of carbonic of two instruments, called cards, to comb, disentanoxide are composed of 50 of oxygen, united with gle, and arrange the hairs or fibres thereof for spinprecisely the same quantity of carbon as is con- ning, &c. Before the wool is carded, it is coated tained in 100 measures of carbonic acid. Conse- with oil, whereof one-fourth of the weight of the quently, the composition of carbonic acid being, wool is required for wool destined for the woof of stuffs, and one-eighth for that of the warp. By volume, Vapour of carbon, 100 Oxygen gas, 100 CARDINAL POINTS; the four intersections of the horizon with the meridian and the prime vertical circle. They coincide with the four cardinal regions of the heavens, and are, of course, 90° distant from each other. The intermediate points are called collateral points. CARDS, PLAYING, are pieces of thin pasteboard, of an oblong figure, and with us commonly about 34 inches long and 24 broad; on which are printed a variety of points and figures; a certain number or assemblage of which serve for the performance of various games, as ombre, picquet, whist, &c. A full pack consists of fifty-two cards. The inventor of cards is not known, nor even the age when they first appeared; but judging from the material they were originally made of, viz. leaves of paper, they appear to be prior to the time of Charlemagne. The Hon. Daines Barrington, Mr. Bowles, and Mr. Gough, in their three essays on the " Antiquity of Card-playing," seem to agree that the Spaniards have the best pretensions to be considered as the original inventors of this amusement. Others have traced their invention to about the year 1390, for the purpose of diverting Charles VI., then king of France, who had fallen into a deep melancholy, and ascribe it to Jaquemin Gringonneur, a painter in Paris. Accordingly, in the accounts of the treasurer of that prince, the following article occurs: Paid fifty-six shillings of " smell. CARMINATIVE, in Medicine; a denomination formerly applied to those articles of the materia medica which possess the property of dispelling wind from the stomach. CARMINE, the most splendid of all the red colours, is made from the cochineal insect, or coccus cacti. It is deposited from a decoction of powdered cochineal in water, to which alum, carbonate of soda, or oxide of tin, is added. As the beauty of this valuable colour is affected not only by the mode of applying it, but also by the quantity of the ingredients mixed with it, we find various recipes for the preparation of it. The manufactories which prepare the best carmine carefully conceal the method. The best natural cochincal is found in Mexico. Paris, to Jaquenin Gringonneur, the painter, for three | crystalline points of a very bitter taste and very faint packs of cards gilded with gold, and painted with divers colours and divers devices, to be carried to the king for his amusement." From this item of account it appears, that the playing cards were originally very different in their appearance and price from what they are at present. They were gilt, and the figures were painted or illuminated, which required no little skill and genius, as well as labour. This last circumstance is one reason that playing cards were little known and used for several years after they were invented. By the four suits or colours, the inventor might design to represent the four states or classes of men in the kingdom. The coeurs, or hearts, denote the gens de choeur, choir-men or ecclesiastics. The nobility or principal military part of the kingdom is represented by the ends or points of lances or pikes, which, through ignorance of the meaning of the CARNATION, in the Fine Arts; the colouring of the figure, we have called spades. By diamonds are flesh of the human body. The use of carnation designated the order of citizens, merchants, and requires very attentive study and great skill in the tradesmen. The trefoil leaf, or clover grass, incor- artist. It varies with the sex of the individual, with rectly called clubs, alludes to the husbandmen and the classes and countries to which the subjects belong, peasants. The four kings are David, Alexander, with the passions, the state of the health, &c. The Cæsar, and Charles, representing the four celebrated | cheeks are, in a healthy subject, of a lively red; the monarchs of the Jews, Greeks, Romans, and Franks, breast, neck, and upper part of the arms of a soft under Charlemagne. The queens represent Argine (for white; the belly yellowish. At the extremities the regina, queen by descent), Esther, Judith, and Pallas; colour becomes colder, and at the joints assumes a which are typical of birth, piety, fortitude, and wis-violet tint, on account of the transparent appearance dom. The knaves denote the servants to the knights. of the blood. All these shades require to be softly The first certain notice of their having been known blended. Two faults in carnation are chiefly to be in England occurs in a record in the time or Edward avoided-hardness, the fault of the masters of the IV. On an application of the card-makers of London 15th century, and too great weakness. Guido Reni to Parliament, A. D. 1463, an act was made against not unfrequently painted his flesh so that it appeared the importation of playing cards. From this statute almost bloodless. The French school has gone farit appears, that both card-playing and card-making thest in this respect. The flesh of the followers of were known and practised in England before this this school often looks like porcelain or wax. Titian period, or about 50 years after the era of their sup- is still unrivalled in carnation. posed invention. Mr. Gough observes, that the use CAROTID, in Anatomy; a name given to the large of cards among the Chinese is evident, not only from arteries which supply the head, from a mistaken a Chinese painting, which represents their ladies notion that tying these vessels would induce sleep.— playing at a game with something much thicker in There are two common carotid arteries, a right and substance than cards, yet shaped and numbered like left; of which the former is a arch of the arteria them, but also from a pack of Chinese cards in his innominata, the latter arises from the branch of the possession, made of the same materials as the Eu-aorta. Each of these vessels are again divided into ropean. However, the devices on the cards are very different from those known in this part of the world. CAREENING (in French, faire àbattre, carèner); heaving the vessel down on one side, by applying a strong purchase to the masts, so that the vessel may be cleansed from any filth which adheres to it by careening. A half careen takes place when it is not possible to come at the bottom of the ship; so that only half of it can be careened. an external and internal carotid artery. CARPETS are thick textures, composed wholly or partly of wool, and wrought by several dissimilar methods. The simplest mode is that used in weaving Venetian carpets, the texture of which is plain, composed of a striped woollen warp on a thick woof of linen thread. CARIBBEE BARK. Under the general denomina- Kidderminster carpeting is composed of two wooltion of cinchona, several barks have been compre-len webs, which intersect each other in such a manhended which are not the products of the real cincho- ner as to produce definite figures. na, and which, in fact, neither contain cinchona nor quinia, and cannot, consequently, be substituted as a febrifuge for the true species of cinchona. One of the principal substitutes of this kind is the Caribbee or St. Lucia bark, which is procured from the exostema Caribea (Persoon), a tree growing in the West Indies. This bark is in convex fragments, covered with a yellow epidermis, commonly thin, but sometimes hard and spongy, with deep fissures, of a yellow, red, or brown tint internally, of a fibrous texture, offering here and there small shining and ARTS & SCIENCES.-VOL. I. Brussels carpeting has a basis composed of a warp and woof of strong linen thread. But to every two threads of linen in the warp, there is added a parcel of about ten threads of woollen of different colours. The linen thread never appears on the upper surface, but parts of the woollen threads are from time to time drawn up in loops, so as to constitute ornamental figures, the proper colour being each time selected from the parcel to which it belongs. A sufficient number of these loops is raised to produce an uniform surface. To render them equal, each row passes S over a wire, which is subsequently withdrawn. In | An engraved representation of an ancient carriage some cases the loops are cut through with the end with horses will best illustrate their general form. of the wire, which is sharpened for the purpose, so as to cut off the thread as it passes out. In forming the figure, the weaver is guided by a pattern which is drawn in squares upon paper. Turkey carpets appear to be fabricated upon the same general principles as the Brussels, except that the texture is all woollen, and the loops larger, and always cut. The English and Americans are the only nations among whom carpets are articles of general use. CARRIAGE. The employment of wheel carriages may be traced to a very early period, and their usefulness principally arises from their power of diminishing friction. This important desideratum is effected by changing the rubbing motion of a sledge into the rolling motion of a cylinder. Thus wheels were probably at first but rollers. Whether their application to the removal of timber and heavy loads was accidental, or the invention of some early mechanic, is now but of little consequence to deter mine. To improve these embryo germs of mechanism, and bring them into the form of wheels supporting a load upon an axletree, required a considerable degree of ingenuity; they must at first have been solid, the axletree must have been originally made of wood, and was probably fixed in the wheels, and moved round under the shafts or body of the carriage, as is common at present in the Irish car. The use of iron gudgeons, or iron axletrees, could not have been common in the first stages of civilization, and the separation of the wheels from the axletree was therefore of later date. Yet in the earliest authentic history which exists, chariots are mentioned as in use for pleasure, for war, and for carrying burthens. Whilst carriages were used, where no regular roads had been made, the mechanical advantages of high and low wheels were not of consequence; the safety of the driver was the principal object. The height of the wheels was determined by the convenience of the warrior, and they were made of such a height as to permit him, encumbered with his armour, to ascend and descend with facility. We accordingly find in all ancient gems and monuments, that from the earliest antiquity the ancient war chariot had low wheels, the front part of the chariot high, to protect the warrior, the hinder part low and open, to permit him to mount and to descend easily; the pole was attached to the yoke that lay on the horse's withers, without any harness, but a collar round his neck, and two straps to hold it on. A metal chariot of a similar construction was dug up at Rome about the beginning of the present century. As warriors generally employed more horses than were required for their weight and that of the car which bore them, there was no necessity for inquiry into the best form and size of wheels, or of any nicety in the means by which the horses were attached to the carriage. We read of no carriage drawn by one horse only, two horses were usually employed. In Homer, the chariots of Achilles and of other warriors appear to be drawn by two horses; but in some ancient gems it appears that chariots were drawn by four, six, and eight horses; and on one beautiful gem, in honour of a victor at the Olympic games, the chariot is drawn by twelve horses abreast. In coaches, and all other four-wheeled carriages, the fore-wheels are made of a less size than the hind ones, both on account of turning short, and to avoid cutting the braces: otherwise the carriage would go much easier if the fore-wheels were as high as the hind ones; and the higher the better, because they would sink to less depths in the small hollows in the roads, and be the more easily drawn out of them. But carriers and coachmen give another reason for making the fore-wheels much lower than the hindwheels; namely, that when they are so, the hindwheels help to push on the fore ones: which is, however, too unphilosophical and absurd to deserve a refutation. In the preceding observations, we have supposed the rims of the wheels to be cylindrical. In concave wheels, however, the rims are uniformly made of a conical form, which not only increases the disadvantages that we have ascribed to them, but adds many more to the number. Mr. Cumming, in a valuable treatise on wheel carriages, solely devoted to the consideration of this single point, has shown, with great ability, the disadvantages of conical rims, and the propriety of making them cylindrical; but we are of opinion that he has ascribed to conical rims several disadvantages which arise chiefly from an inclination of the spokes. He insists much upon the injury done to the roads by the use of conical rims; yet, though we are convinced that they are more injurious to pavements and highways than cylindrical rims, we are equally convinced that this injury is occasioned chiefly by the oblique pressure of the inclined spokes. The defects of conical rims are so numerous and palpable, that it is wonderful how they should have been so long overlooked. Every cone that is put in motion upon a plane surface, will revolve round its vertex, and if force is employed to confine it to a straight line, the smaller parts of the cone will be dragged along the ground, and the friction greatly increased. Now when a cart moves upon conical wheels, one part of the cone rolls while the other is dragged along, and though confined to a rectilineal direction by external force, their natural tendency to revolve round their vertex occasions a great and continued friction upon the linchpin, the shoulder of the axletree, and the sides of deep ruts. As the rims of wheels wear soonest at their edges, they should be made thinner in the middle, and ought to be fastened to the fellies with nails of such a kind, that their heads may not rise above the surface of the rim. In some military waggons, we have seen the heads of these nails rising an inch above the rims, which not only destroys the pavements of streets, but opposes a continual resistance to the motion of the wheel. If these wheels were eight in number, the wheel would experience the same resistance as if Each wheel, axle, The present invention is intended to remove this disadvantage, which will be better understood by an engraving. it had to surmount eight obstacles, one inch high, I being thereby greatly depressed. during every revolution. The fellies on which the and spring, therefore is occasionally required to suprims are fixed, should in carriages be three inches port double the weight that they are designed to and a quarter deep, and in waggons four inches. carry; and this being thrown upon them suddenly, The naves should be thickest at the place where the renders it necessary to construct those parts of the spokes are inserted, and the holes in which the spokes carriage of double the strength that would otherwise are placed should not be bored quite through, as the be thought desirable. grease upon the axletree would insinuate itself between the spoke and the nave, and prevent that close adhesion which is necessary to the strength of the wheel. A coach has been defined, "a convenient carriage suspended on springs, and moving on four wheels," intended originally for the conveyance of persons in the upper circles of society, but now become very common among the middling classes in almost all civilized countries. The fashions, with regard to the form and ornament of coaches and other carriages for pleasure, are perpetually changing; the chief kinds now in use are, the close coach and chariot, the landau, which can lower its roof and part of its sides, like the head of a phaton; the barouche, or open summer carriage, made on the lightest construction; the chariot, which is intended only for two or three perthe landaulet, or chariot whose head unfolds back; in addition to which there is the britscha, a carriage now very generally employed. These all run upon four wheels. Of the two-wheeled vehicles, there is the curricle, drawn by two horses, each bearing on a narrow saddle the end of a sliding-bar or yoke that upholds a central pole; the gig, chaise, or wiskey, that have each only one horse, which moves between a pair of shafts, borne nearly horizontally, by means of a leathern sling passing over the saddletree. When a gig, &c., has two horses, one preceding the other, in harness, the machine and its horses are, taken together, denominated a tandem. In addition to these we have a tilbury, a cabriolet, and a Stanhope. sons; A circular horizontal locking-wheel, formed of iron, is attached to the front part of the carriage. This bears upon the axletree bed and upon segMr. Fuller has effected a considerable improve-ments supported by iron arms, and is enabled to ment on light four-wheel carriages, which is deserving of notice. It consists in the adaptation of an apparatus to the front part of the vehicle, which is designed to prevent the carriage from overturning, by preserving the body at all times in a horizontal position, even when one of the wheels accidentally passes over a large stone in the road, or up a bank by the road side, or any other obstruction which would overthrow a carriage built upon any of the ordinary plans at present in use. turn round horizontally upon these bearings in the act of locking; the axletree bed itself being attached to, and supported by the front springs. A bar crosses the middle of the locking-wheel, and is attached to it by ears and bolts, the centre of this bar having a circular hole, through which a pin passes for the purpose of forming the pivot or axle on which the locking-wheel turns. The extremities of the bar, which extend beyond the wheel, are made truly cylindrical, and to these are attached the plummerboxes, or gudgeons, from whence the bent arms extend for the purpose of supporting the front part of the body of the carriage, as seen in the figure. The principle of this invention will perhaps be best understood, by first pointing out the difficulty with which four-wheeled carriages are drawn over impediments, or uneven roads. Stage coaches are par- It will now be perceived, that in the event of one ticularly subject to this disadvantage, as will appear of the fore-wheels running over a large stone, or any upon a slight view of these vehicles, which are usu- other elevated obstruction in the road, the axletree ally made as follows:-The body part being intended will be thrown out of its horizontal position; but to bear the weight of fifteen persons with luggage, the body of the carriage in front being supported must be very securely framed together, and conse-solely upon the pivots at the ends of the bar, the quently cannot admit of the least flexibility. The plummer-boxes will turn upon the pivots, and cause carriage, therefore, in accommodating itself to the the bent arms to keep the body of the carriage in its unevenness of the roads, must frequently run upon erect position, although one of the fore-whe ls is three wheels, and thereby be subjected to very con-raised up so considerably. siderable strain; for it is evident, that if one corner A very ingenious drag for vehicles descending hills be raised by a wheel passing over a stone, or any other sudden rise in the road, that one half of the carriage will be raised at the same time, and the whole weight of that half so lifted will be supported by the elevated wheel, and its axle and springs at the corner, which passes over the obstacle; the spring has been contrived by Mr. Rapson, which is well worthy of notice. This drag is to be applied to the naves of the carriage wheels, with a chain attached, fastened to the breeching of the horse, and a small pin on each side of the shaft is to go into the bar of the drag. If one of these pins be taken out, the wheel will be dragged, but the other will of course these vehicles, may be reduced to a great extent. turn freely; and by leaving out both pins, the wheels are acted upon in conjunction, during the descent, by the breech bearing against the horse. a It may be proper to add, that a vehicle of this description is now exhibiting in London, weighing five tons! The possibility of their general employment on common roads has now ceased to be problematic; and there is no doubt but that we shall be enabled to congratulate our readers on their complete success, when describing their mechanical structure, under the article STEAM CARRIAGES. CARRONADES (from the river Carron, in Scotland, where they were first made); a sort of artillery resembling howitzers. They are of very large caliber, and carry balls, shells, or cartouches. They are much lighter than common cannon, and have a chamber for the powder like mortars. They ar mostly used on board of ships in close engagements from the poop and forecastle. Sometimes they are In the first of these diagrams we have a representation of the break attached to the carriage, but inoperative; as it will be seen that the chain c, and bolt b, admit the jointed circle to remain at some dis-employed in fortifications. They have been cas tance from the nave of the wheel. In the second figure, the entire frame, a, b, c, are seen in direct collision with the nave, and act by their friction to retard the wheel; this, however, does not occur till the breeching of the harness is drawn tight by the descent of the carriage on an inclined road. We have now to notice a form of vehicle which under most circumstances seems likely to supersede those now in use. We need hardly add, that we allude to the carriage propelled by steam; an engraving of one of these vehicles, copied from Mr. Gordon's valuable treatise on locomotion, may be found interesting. "Soon shall thine arm, unconquered steam, afar Drag the slow carriage, and impel the rapid car; Or on wide-waving wings expanded bear The flying chariot through the fields of air." Now the steam-boat and steam-carriage have already been placed in practical operation; and Sir George Cayley, in a very ingenious paper in the Philosophical Magazine, furnishes data which show the aerial carriage to be any thing but wild or visionary. Carriages of this description vary very considerably in their weight, from four or five tons, down to as many ounces. The Editor of this work has one which goes at the rate of nine miles per hour on a level road, and yet weighs less than one pound. He possesses another, which is under the entire controul of the conductor, carries two persons, and weighs less than one hundred weight; so that the enormous mass of iron now generally employed in from 12 to 68 pounders. They were first used in the North American revolutionary war. CART. See CARRIAGE. CARTILAGE is a semi-pellucid substance, of a milk-white or pearly colour, entering into the composition of several parts of the body. It holds a middle rank, in point of firmness, between bones or hard parts, and the softer constituents of the human frame. It appears, on a superficial examination, to be homogeneous in its texture; for when cut, the surface is uniform, and contains no visible cells, cavities, nor pores, but resembles the section of a piece of glue. It possesses a very high degree of elasticity, which property distinguishes it from all other parts of the body. Hence it enters into the composition of parts whose functions require the combination of firmness with pliancy and flexibility, the preservation of a certain external form, with the power of yielding to external force or pressure. Anatomists divide cartilages into two kinds, the temporary and the permanent. The former are confined to the earlier stages of existence; the latter commonly retain their cartilaginous structure throughout life. The temporary cartilages are those in which the bones are formed. All the bones except the teeth are formed in a nidus of cartilage. The permanent cartilages are of various kinds. They compose the external ear and external aperture of the nostrils and eyelids. The larynx is formed entirely of this substance, and the trachea or windpipe, with its branches, is furnished with cartilaginous hoops, by which these tubes are kept permanently open for the ready passage of air to and from the lungs. The bodies of the vertebræ are joined by large masses of a peculiar substance, partaking of the properties and appearance of cartilage and ligament, which allow of the motions of these parts on each other, without weakening the support that is afforded to the upper parts of the body in general, and to the head in particular, by the vertebral column. These cartilages impart great elasticity to the spine, by which the effects of concussion from jumping, from falls, &c., are weakened and destroyed before they can be propagated to the head. When the body has been long in an erect position, the compression of these cartilages, by the superior parts, diminishes the height of the person. They recover their former length when freed from this pressure. Hence a person is taller when he rises in the morning, than after sustaining the fatigues of the day, and the difference has sometimes amounted to an inch. Cartilages are |