cochinchensis of Louriero), as the source of the Siam camboge; while that of Ceylon is stated to be obtained from the Xanthochymus ovalifolius. (Roxb.) Others assign the Ceylon camboge to the Mangostana Morella. (Derous. in Lamarck, Encyclo.' vol. iii. p. 701.) This last point it is of less importance to settle, if the statement of Dr. Christison be correct, that Ceylon camboge is not now an article of European commerce, all that is found in the markets of this country coming from China. From the bruised leaves and young branches of the first-mentioned tree flows a yellow juice, which is received in cocoa-nut shells or earthen vessels; it is then allowed to thicken, and afterwards formed into rolls. This is the finest sort, called the pipe camboge of Siam. A portion is formed into round cakes, which are either entire or have a hole in the centre. This is the cake camboge of Siam. The juice from the Xanthochymus ovalifolius flows spontaneously, but sparingly; it is increased by incisions in the stem, and by kindling fires in the vicinity of the tree. The colour of both kinds differs according to the season of the year, the age, and part of the tree from which the juice is obtained. The Siam camboge occurs in pieces of variable size, externally of a dirty yellowish brown colour, covered with a fine yellow powder. When broken they exhibit a conchoidal or vitreous fracture, with a brown or saffron-yellow colour. At the ordinary temperature of the air camboge has little smell, but when heated it gives out a very peculiar one. Taken into the mouth it has scarcely any perceptible taste, but upon being chewed for some time it causes a sharp, somewhat acrid feeling, ending in a sweet sensation, accompanied with dryness in the mouth. It excites afterwards a flow of saliva, which is coloured yellow. Its specific gravity is 1.207. A specimen of pipe camboge of Siam, analysed by Dr. Christison, yielded as follows:

The cake camboge is not entirely a natural production, but a manufactured article.

Camboge is almost entirely soluble in alcohol, and is not precipitated from solution by the addition of water. With water it forms an emulsion in which the resin is kept suspended by the gum. It is soluble in the alkalies. The resin may be considered its active principle. It is remarkable that a substance possessed of such slight sensible qualities, having no smell, and scarcely any taste, should be so powerful in its action on the human frame. It is a drastic purgative; and in combination with alkalies, forms a most powerful hydragogue cathartic, occasioning numerous copious watery motions. In an overdose it causes excessive purging, sometimes vomiting; and if taken in large quantity, it produces inflammation of the intestines, mortification, and death.

The diseases in which it is most useful are ascites, or dropsical accumulations in the cavity of the abdomen, especially if accompanied with obstructions in the liver, or other abdominal viscera. It has also been employed against the tape-worm, and obstinate or habitual constipation. The doses must be carefully regulated, and only taken by the order of an intelligent and responsible medical attendant. Its use as a quack medicine has led in many cases to fatal results.

Yellow juices, which when inspissated form a substance resembling camboge, are obtained from several trees, both of the tribe of Guttiferæ and Hypericaceae. Garcinia pictoria is stated by Mr. Royle ( Flora of the Himalaya,' p. 132) to yield a camboge, which in its crude and unprepared state is superior to every other kind; but it is not so permanent. The Garcinia celebica (Linn.) likewise furnishes some. Several species of Vismia (Hypericaceae) yield an American camboge of good quality;-V. sessilifolia (Pers.), V. guianensis (Pers.), V. cayennensis (Pers.), V. micrantha (Mart.), Vismia baccifera (Mart.). The Hypericum pomiferum (Roxb.) also yields a sort of camboge; and the Argemone mexicana.

Camboge is more extensively used as a pigment than as a medicine. An artificial camboge is manufactured with turmeric and other materials. This should always be rejected.

CAMBRIC is one of the numerous varieties of flax or linen manufactures. It is supposed to have derived its name from having been first made at Cambray. It bears much the same relation to linen that muslin does to calico, being a very fine and thin fabric. Scotch cambric, now manufactured in large quantities, is a kind of imitation cambric, made from fine hard-twisted cotton. The French material batiste is a sort of Scotch cambric, to which dyes and printed colours are applied.

French cambrics are imported and Scotch cambric exported to some extent, but do not figure largely in the Board of Trade returns.

ARTS AND SCI. DIV. VOL. II.

CAMELLIA JAPONICA, or Japan Rose. The botanical description of this plant has been given in the NAT. HIST. DIV. [CAMELLIA.] All the varieties of Camellia Japonica succeed best when treated as conservatory plants; that is, planted in the open border under glass, protected from frost, and freely exposed to light and air. They then grow into large evergreen bushes, covered with a dense foliage, upon which their gaudy flowers are beautifully relieved, and are far handsomer objects than when their roots are confined within the narrow compass of a garden-pot. Many of the varieties are nearly hardy, that is, they can bear the ordinary winters of England almost without protection; but then they are so very inferior to conservatory specimens, as to be little worth the having as out of door shrubs, unless upon our southwest coast, in some of the warm bays of Devonshire and Cornwall. They are multiplied by cuttings, grafts, and buds, and also by seeds; there are hundreds of varieties; the best are the double-white, the double-stripe (with the Donkelarii, which has a red and white stripe in a different style), the C. myrtifolia, Chandleri, and punctata. They thrive best in half loam from rotted turfs, and half turfy peat, broken up very fine. After they have bloomed, or even while flowering, buds will be formed for the succeeding season. These, when forming at the top, or on long straggling branches, should be carefully pinched off, in order to induce the plant to become thick and bushy, as well as to prevent its wasting its strength; while all the buds that are wellplaced should remain. After the plant has done flowering, it should be pruned of all useless or unsymmetrical branches. If they require to be shifted from one pot to a larger, this is the time for doing so. The plants may then remain in the greenhouse, where they should be secured plenty of air, but shaded from the sun during the hottest parts of the day, until they have made their growth. They should now be placed out of doors, sheltered from the mid-day sun, and guarded from high winds, until it is time to return them to the conservatory, which is about the month of September, so as to avoid the effects of the early frosts.

The Camellia reticulata, one of the finest species of the genus, remarkable for its net-marked leaves, and its semi-double rose-coloured flowers, can only be brought to perfection by being treated as a conservatory plant, and planted in a pit or greenhouse, in the open mould. If confined in a pot, its leaves are apt to become white and unhealthy. If placed in a bright hothouse, its leaves and flowers are rendered much deeper-coloured, but altogether smaller, and the shoots more stunted. This sort will not easily propagate, either by buds, or cuttings, or grafts, like the common camellia, but requires to have its young wood inarched upon healthy young camellia stocks, when it takes freely; but the parent plant, if many of its shoots are thus treated, suffers so much from the mutilation attendant upon the process, that it is two or three years before it is sufficiently recovered to submit again to the operation. CAMELOPA'RDALUS, the camelopard or giraffe, a constellation formed by Hevelius. A line drawn from Capella to the pole-star passes right through the body of the constellation: the hind part precedes in right ascension, of which the whole ranges from four to eight hours. The letters are of course not in Bayer. The following are the principal stars :— No. in Catalogue

CAMEO, a gem or stone engraved in rilievo; that is, in which the object represented is raised above the plane of the ground, in contradistinction to INTAGLIO, in which the subject is incised, or indented: strictly speaking the term cameo refers to such stones only as have strata or grounds of different colours. There has been much unsatisfactory discussion respecting the origin and exact meaning of the word cameo, and Ducange, Lessing, and others have quoted various ways of writing it.

The art of engraving stones is of high antiquity: but it was at the earlier periods, for the most part confined to intaglio, or indenting, a simpler and an easier process than relieving the work from a ground; and as such stones were used for signets or seals in very remote ages (Exod. xxviii. 11, 21, &c.), the intaglio mode of working seems to be the most natural as well as the best adapted to the purpose. For intaglios, transparent stones of a single colour, or at most clouded stones (as the agates), were used; but for cameos, stones variegated in colour, or with colour in thin strata, as the onyxes and sardonyxes, were employed; artificial stones were also used.

It has been supposed that the Etruscans had the art of engraving hard stones before it was known to the Greeks; and from the forms resembling those of the scarabaei of the Egyptians, it has been thought that the Etruscans derived their knowledge from Egypt. Many engraved stones however that are called Etruscan, are doubtless early Greek, as may be inferred from their subjects, and from the occurrence in the inscriptions of characters of a Greek form.

The earliest Greek artist distinctly mentioned as an engraver of stones, is Theodorus of Samos; Herodotus (iii. 41) tells us that the famous ring of Polycrates 66 'was the work of Theodorus, the son of

M M

Telecles the Samian;" though some writers speak of Mnesarchus, the father of Pythagoras, as an engraver of signets. There has been much discussion respecting the age and genealogy of Theodorus of Samos, and whether there were one or two sculptors of that name; the probability is that there were two, but the date of the Theodorus referred to by Herodotus is pretty well determined by the circumstance for which the historian mentions him, Polycrates having been murdered in 522 B.C. It is not, however, in the opinion of some, absolutely clear whether Theodorus engraved the stone or merely chased the metal of the ring of Polycrates. (Müller, Archäol. der Kunst.,'$97.) The first name of very great note that occurs in this branch of art is that of Pyrgoteles, who lived in the time of Alexander the Great, and who alone was permitted to engrave the portrait of Alexander. Tryphon deserves mention also in this place, being the author of a beautiful and well known cameo in the Marlborough collection, representing the marriage of Cupid and Psyche. He is supposed, on good authority, to have lived under the immediate successors of Alexander in Macedon.

The age of Augustus is remarkable for the excellence of the gemengravers who were then living. Among these Dioscorides, or more correctly Dioscourides, held the highest rank. He seems, however, to have worked chiefly in intaglio. Some of his productions have reached our times, and prove that the estimation in which he was held was not undeserved. Dioscorides was under Augustus what Pyrgoteles had been under Alexander. From Augustus down to Marcus Aurelius there were engravers of gems, both in cameo and intaglio, of very distinguished merit. They were chiefly Grecian artists who settled in Rome. There were, however, some Roman gem-engravers who held a respectable rank, but the list is not considerable.

The Greek artists preferred representing the naked figure, and the finest works produced in Greece are seldom draped, while those executed in Rome, whether by native or by Greek artists, are for the most part clothed. Dioscorides continued to follow the taste of his own nation, and all his figures, with the exception of a Mercury, in the cabinet of France, are believed to be naked.

It is impossible to describe works of this sort, containing so much fine detail, with sufficient accuracy to convey a just idea of their merits. They must be seen and examined with care, to be properly appreciated. Celebrated cameos are preserved in most of the great museums of Europe. One of the most famous works is that known as the Gonzago cameo, which has the heads of Ptolemy II. and Arsinoë I. nearly six inches long; it is now in the possession of the Emperor of Russia. Another of the finest cameos known is the Apotheosis of Augustus, in the collection at Vienna. It represents Augustus, his wife Livia, as Rome, accompanied by her family, with Neptune and Cybele; another is of an Imperial Eagle; also a Ptolemy and Arsinoë, &c., &c. In the French collection the sardonyx of Tiberius is one of the best known: it exhibits the Apotheosis of Augustus and the princes of the house of Tiberius; a Jupiter Ægiochus is a very fine specimen to which may be added the Apotheosis of Germanicus; and one of Agrippina and Germanicus; with others, particularly some portraits of great interest. We possess in this country some camei of first-rate excellence, but they are chiefly in private collections. Almost without exception the most famous works of this kind are remarkable for the different strata or zones of colour which they exhibit, as well as for their exquisite design and execution.

The ancients were fond of decorating their drinking-cups with precious stones and camei. They called such vessels' gemmæ potariæ.' Many of them are preserved in the cabinets of the curious. They are usually of sardonyx.

The workers in cameo not only exercised their skill in the cutting or engraving, but also in so arranging their subject and the composition of its details as to make the different colours or zones of the stones answer for parts of the design; as, for example, in relieving fruit, flowers, or drapery, in colour, while the other parts, as the flesh of a portrait or figure, were left white; or cutting the subject entirely in white, and working no deeper into the stone than the first layer of colour; thus making, or rather leaving, a natural dark back-ground for the design. These irregularities or accidents, are sometimes taken advantage of so skilfully, that it is very difficult to decide whether the variety is the effect of art, or really the natural colour of the stone.

The ancients were so partial to this variously-coloured work, that they imitated the material, in glass or paste, and exquisite specimens of ancient pastes occur in the museums of this country and the

continent.

the names of some who exercised it will bear comparison with those of almost any age. The greater part of these were Italians, but two of the most celebrated were natives of Germany, and are justly entitled to particular commemoration. The works of John Pickler and Lawrence Natter challenge competition with the finest antiques. Natter has left a valuable work on his art, entitled 'De la Méthode Antique de graver en Pierres fines,' &c. Raspe's Catalogue of Tassie's Gems' may also be consulted with advantage by those who desire to extend their knowledge on this subject; as well as the works of Millin, Introduction à l'Étude des Pierres gravées;' Raoul Rochette, Lettre à M. Schorn;' Visconti, Iconographie Grecque;' 'Impronte Gemmarie dell' Instituto;' Müller, Archäologie der Kunst,' §§ 313-315, &c.

the pencils of rays proceeding from it fall on the surface CD at an angle of 45° or nearly so, and therefore by the preceding principle, are reflected on AD, and again from A D to the eye, through an opening KL, which excludes all except the end of the prism at A, and a part of the sheet of paper or other flat surface GH. Hence the image of qis thrown towards the visible part of the paper, and the eye viewing both the image and the sheet of paper (with different parts of the pupil, however, which creates a difficulty in using this instrument) the observer is enabled to trace the object upon the paper by means of one of the following adjustments:

1. If q be very distant, so that the rays of the pencils are nearly parallel, those rays will emerge nearly parallel, or the image will be at about the same distance beyond GH in appearance as the object Qis beyond B C. But the image must appear to be thrown upon the paper, or it cannot be distinctly traced. Either therefore the image of the paper must be removed to that of the object, or that of the object must be brought up to the paper. For long-sighted people, or those who see objects best at a distance, the first is most advantageous. It is done by placing a concave glass M, the principal focus of which shall be in or near the paper. The consequence is, that the pencils from the points of the paper are rendered nearly parallel, and by an adjustment for raising or lowering the lens the image of 9 may be made to appear to coincide with that of the paper. But for short-sighted persons, who require near objects or divergent rays, the end may be answered by employing, instead of the convex lens at M, a concave lens at N, which makes the rays of the image diverge, and by adjustment of which they may be brought to appear as pencils diverging from the paper. Mr. Coddington has remarked that this lens must produce an unnecessary distortion of the image, and that a short-sighted person had better use the convex lens at M, in the manner of a long-sighted person; using spectacles, or placing a concave le is at K L, to bring the images nearer, or to render the rays more divergent.

2. When the object q is near the prism, the latter is raised or lowered on its pillar until the paper and the object are at equal or nearly equal distances from the prism. The image of Q will then be thrown on the paper without any necessity for a lens.

The camera lucida thus described presents the objects direct, and without reversal of left and right; but it is by no means an easy instrument to use. There is what is called a knack, which some can acquire, and some cannot. It has been found of considerable use by travellers who were unable to draw from nature, but it is at best little better than a toy, and thus it has been in a great measure superseded even for unartistic travellers by the photographic camera. CAMERA OBSCURA, the dark chamber, an instrument by means of which images of external objects are thrown upon a plane surface, or, as it is termed, focussing screen.

The earliest description of the camera obscura is in the seventeenth book of the Magia Naturalis' of John Baptista Porta, who directs to make a small aperture in the shutter of a perfectly dark room, and to let the light fall upon a white screen or wall. It is evident that in Fig. 1. A

B

this way inverted images will be obtained, the magnitude of which | will depend upon the distance of the screen from the aperture. Porta makes one more step towards the present instrument. He states, as a secret which he had concealed till then, and had intended always to conceal, that if a convex glass be applied to the aperture, all external objects shall be seen as clearly as to a bystander, with so much pleasure that those who see it can never enough admire it. He does not appear to have found out that the screen should be curved, in order that the points of convergence of all the pencils should fall exactly upon it. The present form of the common camera obscura is as follows: The box in the diagram has a tubular lateral opening which should, if the lens be large, be partly closed by a diaphragm to Fig. 2.

diminish the effective aperture. The rays passing through the lens from a distant object are prevented from converging by meeting a mirror inclined at 45° to the bottom of the box, and are thus made to converge at or very near to the glass plate A, one side of which is ground. A shade over the glass plate excludes direct light from falling on it. The under side of the glass plate should be curved; but, generally speaking, the aperture is so small that this is of little consequence for ordinary purposes. The tube in which the lens is placed is made to slide, so that it can be adjusted to near or distant objects. The instrument being adjusted, the landscape directly in front of the object-glass will be painted on the glass A and not inverted, but only the right side on the left, and vice versa.

A camera obscura for exhibition, such as is now most commonly seen at summer watering-places, is generally made in a room with a conical roof and an aperture at the top. Above this aperture is a revolving plane mirror inclined at 45°, and reflecting pencils downwards. A convex lens causes these pencils to converge upon a surface of plaster of Paris, properly curved. The mirror evolves about a vertical axis, thus allowing all the compass-points of a landscape to be successively thrown on the surface.

On these instruments we may observe that they are artificial eyes. The rays are collected by a lens or prism, and are then made to paint images upon a surface, which answers to the retina. Or conversely we may say that, in the common experiment of cutting away part of the eye of a dead animal to show the images on its retina, the eye thus employed is converted into a camera obscura.

Prior to the discovery of photography, the camera obscura was only an elegant scientific toy; but the important part it was made to

play in that beautiful art at once raised it to the rank of a philosophic instrument, and its adaptation to the peculiar requirements of the art has been a subject of continuous and careful investigation. In form, as in principle, the photographic camera differs little from that above described. But the only light admitted into the camera must pass through the lens, and the image, instead of being reflected by a mirror on to the horizontal ground-glass screen A, is thrown at once upon the screen itself, which is upright and corresponds to the back of the camera in fig. 2, or to the screen в in fig. 1. The screen (in photographic cameras called the focussing screen) is of ground glass, as in the ordinary camera; but in the practice of photography it is only used for ascertaining that the object is correctly placed and properly defined, when it is removed, and the prepared plate or paper substituted.

The great objects to be obtained in photographic cameras are, that the images shall be exhibited on the screen clearly and sharply defined: in their true forms and with their natural light and shade, on a flat plane, that is, and free from all aberration or distortion. In order to effect this, the nicest adjustment of lenses, prepared with the strictest accuracy, are employed. In practice, it is found that only achromatic combinations, in which the chemical and optical foci are coincident, will serve; and that for near objects, as portraits, and for objects which are situated in varying planes, as in landscapes, very different combinations must be used. For portraits, the usual combination is formed by two compound achromatic lenses, the two flint lenses being turned towards each other, and the convex side of the front combination towards the sitter. For landscapes, a meniscus lens, formed of a double convex lens of plate-glass cemented to a double concave lens of flint-glass, is employed, the concave side (which should be very slightly concave) being turned towards the interior of the camera. The varieties of lenses made by different opticians are, however, very great, but a description of them would be out of place here. Among the most successful are the orthoscopic, the Petzval, the aplanatic, &c. The varieties of photographic cameras are even more numerous than of photographic lenses; but none of the varieties involve any material difference of principle. The most usual varieties are such as the folding, the expanding, and the adjusting camera, or some combination intended by the inventor to secure greater accuracy or portability, or to avoid some defect in cameras in ordinary use. For taking stereographs, however, and for copying photographs, prints, &c., on a larger or smaller scale, cameras of a special character are manufactured. The Stereoscopic Camera is, however, little more than a double camera, or two cameras combined in one (and hence sometimes called a double lens, or binocular camera) with adjustments for giving slight independent motion to each for rapidly covering the lenses, &c. The Copying Camera is a more complex apparatus; arrangements having to be provided for lengthening the body of the instrument before as well as behind the lens, altering the place of the lens, focussing-glass, camera-back, dark frame, diaphragms, &c., accor ling to the size of the copy, whether the original is transparent or opaque, &c. Cameras intended for obtaining "instantaneous photographs," as well as for other special purposes, have also been manufactured, among which perhaps might be mentioned Mr. Skaife's ingenious pistol camera.' But for further particulars we must refer the reader to treatises on photography and to the articles LENS and PHOTOGRAPHY,

CAMERONIANS. [CAMERON, RICHARD, in BIOG. DIv.] CAMOUFLET, or STIFLER, is a term applied in military mining to a small charge of powder, or undercharged mine, which makes little or no crater above ground, but by the concussion underground destroys a portion of the enemy's gallery and suffocates his miners. CAMP. [ENCAMPMENT.]

CAMP, ROMAN. There are few parts of the art of war as practised by the Romans in which the laborious and regulated carefulness of that sagacious people is more evident than in their system of castrametation. In the present article we shall give some account of the construction of their camps, and the arrangement of the troops in them.

In speaking of the Roman camps, it is necessary to distinguish between the summer and winter encarnpments (castra æstira et hyberna); and again to discriminate between those camps which were formed to protect the army for a short period, and those which they proposed to occupy for a longer time, which were called castra statira. The difference between these consisted chiefly in the strength of the fortifications, and in the superior size of the temporary camps, which were intended commonly for the whole army, while the more permanent encampments were for divisions of the army. Winter encampments were not used by the Romans in the earlier periods of their history, when their chief wars were little more than summer campaigns, and were waged against neighbouring nations: but in a later age, when permanent conquest was their aim, and the war continued several years, the army was regularly distributed into winter-quarters, and often spread over a considerable extent of country, in order to overawe the subjugated districts, or because forage and provisions could be obtained by the army in several divisions more easily than when it was in one body. Caesar in his Gallic campaigns regularly distributed his army into winter-stations, so strongly fortified that though several attempts were made upon them only one was taken, and that because the commander unwisely abandoned it. (Cæs. 'De Bel. Gal.,' lib. v.)

Perhaps the completest description which we have of a Roman camp may be found in Polybius, who has in the sixth book of his history given a pretty full account of the military tactics of the Romans, part of which, relating to their castrametation, we shall condense with the further information collected by General Roy. Polybius lived at a time when the institutions of the Republic were in their full vigour; he had gained military experience in the armies of his country; and his opportunities of acquiring information, both from personal observation and from the information of others, were ample. The Roman,

legion, we may remark, in the time of Polybius consisted of 4200 infantry (or in time of peculiar emergency 5000 infantry and 300 cavalry. The Consular army was formed of two legions; with a body of allied foot, equal in number to the infantry of the legions, besides the extraordinaries, chosen troops of the allies, who probably amounted to 2100, or when the legion was of 5000 infantry, to 2500; and of allied horse, thrice the number of the legionary cavalry; of these allied horse one-third were drafted for the extraordinaries, making the total of the Consular arıny 18,900, or 22,500 infantry and 2400 horse.

When a place suitable for a camp had been chosen, and the choice of a suitable spot was regarded as a very important part of the commander's duty, the first thing was to fix a standard on the spot judged to be most adapted for overlooking the army when encamped, and sending commands to the different quarters. Round this standard a square of 200 feet was measured, and set apart for the general's quarters: this was called prætorium (A), from the name prætor, which, according to early Roman usage, was the general title of a military commander. On that side of this square inclosure which was deemed most suitable for obtaining forage and water, the bulk of the army was encamped, and that side of the prætorium and the corresponding side of the camp, we shall follow Polybius in calling the front. In front then of the prætorium, distant from it fifty feet, on a line running across the camp, were placed the tents and baggage of the legionary tribunes (BB), who in the ordinary consular army (of two Roman legions with the regular proportion of allies, as already explained) amounted to twelve: and towards either extremity of the same line were the tents of the project (CC) or officers, who held among the allies a rank similar to that of the tribunes in the legions. These tents were pitched with their lacks to the pre

In front of the tribunes' tents, a passage, 100 feet wide, called in our plan the Principia, or principal street (D D), ran across the camp; and between the side of this passage and a line parallel to it, near the front of the camp, the soldiers were encamped in lines, which formed a right angle with the Principia. The soldiers' quarters were divided into two parts by a passage 50 feet wide (E), which ran from the prætorium to the front of the camp. On each side of this street were posted the Roman cavalry, and next to them the Triarii, one of the divisions of the legionary infantry. Next to these were two passages of 50 feet wide (F F F F), and then the Principes and the Hastati, the other divisions of the Roman infantry. The tents of each division fronted the passage next to them, so that when the tents of two divisions, as of the cavalry and the Triarii, and of the Principes and the Hastati, were not separated by an intervening passage, they had their backs to each other. There were in a legion ten turma of the cavalry, and ten manipuli of each division of the infantry; and the turme and manipuli of each division were encamped in one range along the passages, a quadrangular space of 100 feet square being allotted to each turma of cavalry, and each manipulus of the Principes and Hastati, while each manipulus of the Triarii, which had seldom more than half the complement of the other manipuli, had a space of 100 feet by 50.

turmæ.

Beyond the tents of the Hastati on each side was another passage of 50 feet wide (GG GG), and then came the quarters of the allied cavalry, and beyond these again, without any separating passage, the quarters of the allied infantry, whose tents looked toward the ramparts of the sides of the camp. The tents of the allies occupied a space of the same length as that occupied by the legionary soldiers. The depth of their quarters varied with the number of the men: our plan assigns to the cavalry and infantry an equal depth, namely, of 200 feet each; this is probably near the truth. The quarters of the legionary soldiers and the allies were alike divided into two parts by a passage 50 feet wide, called quintana (HH), running across the camp in a direction parallel to that of the Principia, between the fifth and sixth manipuli and The space on each side of the prætorium was occupied, the one side (K) by the quaestor (whose office combined the direction of the commissariat department and the care of the military chest) and the military stores, and the other side (M) by the forum, or place for holding a market and transacting business. Next to these on each side were the quarters (N N) of the chosen troops from the extraordinary cavalry of the allies, who served in the consul's body-guard, and of the volunteers (00) who had engaged in the service from regard to the consul. The tents of these looked towards the quaestor's quarters and the forum. Beyond these on each side, with their tents fronting the rampart of the camp, were the chosen troops (99) from the extraordinary' infantry of the allies, who also formed part of the consul's body-guard. Behind all these, right across the camp, ran a passage or street of 100 feet wide (PP); and beyond this passage, and parallel to it, were the quarters of the main body of the extraordinary' cavalry of the allies (RR); and behind these, looking towards the back of the camp, were the quarters of the extraordinary foot of the allies (ss). The flanks of these quarters (TT) were occupied by any foreigners or temporary reinforcements of allied troops which might be in the camp. Polybius does not assign any particular quarters to the velites, or light armed men. The space occupied by all these quarters formed a square, and on every side was left an interval of 200 feet, which served for various useful purposes, to deposit the booty, to afford space for the troops to enter and leave their respective quarters, and to protect the tents and troops from fire or weapons thrown by any who might assail the camp from without. The whole was surrounded by a rampart (vallum) and a ditch (fossa), through which were four gates or entrances: the Prætorian gate (Porta Prætoria), in front of the camp, opposite the protorium; the Decuman gate (Porta Decumana), at the back of the camp; and a gate at each end of the principia or principal street. If the two consular armies were united, the camp formed an oblong square, and resembled two camps placed back to back, without any intervening intrenchment. It appears to have had six gates, two prætorian and four others, one at each end of the two principal streets or passages.

The vallum was composed usually of earth or turf, sometimes of stones or wood, and was surmounted by a palisade. The ditch was on the outside. In stations which were designed to be permanent, and which were in a disturbed or hostile country, the works were constructed with unusual care, and there are many remains or vestiges of them in different parts of Great Britain. Among the most perfect are those at Ardoch, in Scotland, and Llandrindod in Wales.

The plan of a Roman camp, which we have given, is taken from General Roy's Military Antiquities of the Romans in Britain,' to which, and to G. F. Rettig's Polybii Castrorum Romanorum forma interpretatio,' we refer the reader for many valuable observations on the castrametation of the Romans.

CAMP-SHEETING. An enclosure at the foot of a wall or quay, carried down to the water's edge, for the purpose of limiting the vertical compression of the ground. Camp-sheeting differs from sheet, or close, piling in this respect, that although it is executed with guide piles, whales, and sheeting, all its parts are essentially of small dimensions. It is, in fact, a diminutive sheet piling, in which the total length of the sheeting above and below ground does not exceed ten feet. Sometimes the sheeting of this description of enclosure is laid horizontally, and is spiked at the back of the guide piles which, under these circumstances, are kept very close together. CAMPANILE, an Italian term, signifying a tower for bells. The word is derived from campana, 66 a bell." In many respects the campanile corresponds with the belfry or steeple of the Gothic churches of the North; but the term is usually and very conveniently confined to the Italian bell-towers, which differ from those of the North in being of equal dimensions from the base to the summit, constructed without buttresses, and for the most part terminated without a spire.

The campanile is essentially an Italian structure. It has no prototype in classic architecture; and, when copied even by Romanesque architects beyond the Alps, it was with a difference. Usually, the Italian campanile belongs to a church, if it does not form a part of one; but many, though attached to churches, are civic structures, as that of St. Mark at Venice, and the well-known leaning tower at Pisa; while others, like the Asinelli and Garisenda towers at Bologna, and that of the town-hall, Florence, are entirely municipal in purpose. Very frequently the campanile stands wholly detached from the church to which it belongs, but more commonly it is attached to an angle of the building. Originally the campanile was constructed with a plain solid base,

pierced only with small windows for two-thirds of its height; the upper story or stories having one, two, or more, larger round-headed windows, or an open loggia. Of this kind is the campanile of St. Mark, already alluded to, which was begun in 992, and is one of the oldest campanili left; the heavy upper story is of more recent date. With the introduction of the pointed arch, more of lightness and ornament was imparted to the upper part of these structures, they were more distinctly divided into stories, and they were crowned with a cornice or surmounted with a spire; but the square form was retained, and they remained uniform in size and without buttresses. Sometimes the spires were made octagonal at the base, and much enriched in the lower part; but they seldom harmonise well with the tower, and usually they are of no great elevation, and not remarkable for elegance of outline. Among the most remarkable Italian campanili are those of Cremona, Florence, Ravenna, Padua, Modena, Mantua, Sienna, Bologna, Pavia, Verona, and Pisa.

Some of these campanili are much out of the perpendicular, especially those of Pisa and Bologna. The Garisenda, built by the Garisendi, at Bologna, is 153 feet high, and 8 feet 6 inches out of the perpendicular. Dante has compared this tower to the inclined figure of Antæus. (Dante, 'Inf.' canto xxxi. 1. 135.) The Asinelli tower, also at Bologna, and close to the former, is 320 feet high, and 3 feet 6 inches out of the perpendicular. The leaning tower at Pisa is 150 feet high, and 13 feet out of the perpendicular. The campanile of Cremona is the highest in Italy, having an elevation of 395 feet.

The most remarkable, and in many respects the finest of the Italian campanili, is that of Florence, which is 269 feet high, and was constructed by Giotto in 1324. The plan is a perfect square, 45 feet on each side. The interior is divided into six floors, each of which is vaulted. The tower is ascended by 406 steps. The façade of the tower is Gothic in style, but mixed with somewhat of the Italian taste in architecture, which soon after prevailed over the Gothic. In the cut, the window-shafts appear plain, but in reality they are twisted; and the whole façade is covered with ornament. It is said that Giotto intended to surmount this tower with a spire 85 feet in height. The surface is veneered with coloured marble, which, though structurally objectionable, adds greatly to the richness of its appearance. Among transalpine towers bearing a marked resemblance to those of Italy, one of the most interesting is that of the cathedral at Seville, which is 350 feet high. It is said to have been begun by Abu Yusuf Yacub, in 1196, famous for other great architectural works, and is therefore contemporaneous with some of the most celebrated Italian towers. This tower is called La Giralda, or Girandillo, from a bronze female figure bearing that name; this figure, though it weighs a ton and a half, turns with the wind; it was cast in 1568, and replaced the four brazen balls which formed the original Moorish termination, but which were thrown down in 1395. (Gailhabaud; Street; I'Anson; Fergusson.)

[Campanile of the Cathedral at Florence, designed and built by Giotto.]

Wren, in his church towers, without actually copying Italian campanili, worked much in the spirit of their designers, and produced picturesque structures. Within the last few years, campanili of Italian form have been attached in this country to some churches and chapels built in the Romanesque and pointed Italian styles; and to some Italian renaissance town-halls, corn-exchanges, &c.; and they seem to form a favourite type with architects and civil engineers in constructing chimney-shafts. (See Rawlinson on 'Chimney-Shafts.')