ARCHITECTURE.

Architecture, in its most general sense, is the art of erecting buildings, of any kind. In modern use, this name is sometimes restricted to the external forms, or styles, of building, in which sense, architecture is one of the fine arts. It appears to have been among the earliest inventions, and its works have been commonly regulated by some principle of hereditary imitation. Whatever rude structure the climate and materials of any country have obliged its early inhabitants to adopt for their temporary shelter, the same structure, with all its prominent features, has been afterwards kept up by their refined and opulent posterity. Thus, the Egyptian style of building has its origin in the cavern and mound;[A] the Chinese architecture is modelled from the tent; the Grecian, is derived from the wooden cabin, and the Gothic, from the bower of trees.

Elements.--The essential elementary parts of a building, are those which contribute to its support, enclosure, and covering. Of these, the most important are the foundation, the column, the wall, the lintel, the arch, the vault, the dome, and the roof.

[A] Wilkins's Vitruvius, p. xvii.

Foundations.--In laying the foundation of any building, it is necessary to dig to a certain depth in the earth, to secure a solid basis, below the reach of frost and common accidents. The most solid basis is rock, or gravel which has not been moved. Next to these, are clay and sand, provided no other excavations have been made in the immediate neighborhood. From this basis, a stone wall is carried up to the surface of the ground, and constitutes the foundation. Where it is intended that the superstructure shall press unequally, as at its piers, chimneys, or columns, it is sometimes of use to occupy the space between the points of pressure, by an inverted arch. This distributes the pressure equally, and prevents the foundation from springing between the different points. In loose or muddy situations, it is always unsafe to build, unless we can reach the solid bottom below. In salt marshes and flats, this is done by depositing timbers, or driving wooden piles, into the earth, and raising walls upon them. The preservative quality of the salt, will keep these timbers unimpaired for a great length of time, and makes the foundation equally secure with one of brick or stone.

Column.--The simplest member in any building, though by no means an essential one to all, is the column or pillar. This is a perpendicular part, commonly of equal breadth and thickness, not intended for the purpose of enclosure, but simply for the support of some part of the superstructure. The principal force which a column has to resist, is that of perpendicular pressure. In its shape, the shaft of a column should not be exactly cylindrical; but since the lower part must support the weight of the superior part, in addition to the weight which presses equally on the whole column, the thickness should gradually decrease from bottom to top. The outline of columns should be a little curved, so as to represent a portion of a very long spheroid, or parabolid, rather than of a cone. This figure is the joint result of two calculations, independent of beauty of appearance. One of these is, that the form best adapted for stability of base, is that of a cone. The other is, that the figure which would be of equal strength throughout for supporting a superincumbent weight, would be generated by the revolution of two parabolas round the axis of the column, the vertices of the curves being,at its extremities.[A]

In the accompanying wood cut, No. 1 is the figure having the greatest stability of base; 2, the figure which is of equal strength throughout for resisting vertical pressure; and 3, the intermediate, or common form of the column, a little mare curved than is usual in practice, and having its top truncated, to give stability to the entablature.

The swell of the shafts of columns, was called the entasis, by the ancients. It has been lately found,[B] that the columns of the Parthenon, at Athens, which have been commonly supposed straight, deviate about an inch from a straight line, and their greatest swell is at about one third of their height.

Columns in the antique orders are usually made to diminish one sixth, or one seventh, of their diameter, and sometimes even one fourth. The Gothic pillar is commonly of equal thickness throughout.

Wall.--The wall, another elementary part of a building, may be considered as the lateral continuation of a column, answering the purpose both of enclosure and support. A wall must diminish as it rises, for the same reasons, and in the same proportion, as the column. It must diminish still more rapidly if it extends through several stories, supporting weights at different heights. A wall, to possess the greatest strength, must also consist of pieces, the upper and lower surfaces of which are horizontal and regular, not rounded nor oblique. The walls of most of the ancient structures, which have stood to the present time, are constructed in this manner, and frequently have their stones bound together with bolts and cramps of iron. The same method is adopted in such modern structures as are intended to possess great strength and durability; and in some cases the stones are even dovetailed together, as in the light-houses at Eddystone, and Bell Rock. But many of our modern stone walls, for the sake of cheapness, have only one face of the stone squared, the inner half of the wall being completed with brick; so that they can in reality be considered only as brick walls faced with stone. Such walls are said to be liable to become convex outwardly, from the difference in the shrinking of the cement.

[A] See Tredgold's Principles of Carpentry, p, 50.

[B] By Messrs Allanson and Cockerel. See Brande's Journal, vol. x. p. 204.

Rubble walls are made of rough, irregular stones laid in mortar. The stones should be broken, if possible, so as to produce horizontal surfaces. The coffer walls of the ancient Romans were made by enclosing successive portions of the intended wall in a box, and filling it with stones, sand, and mortar, promiscuously. This kind of structure must have been extremely insecure. The Pantheon, and various other Roman buildings, are surrounded with a double brick wall, having its vacancy filled up with loose bricks and cement. The whole has gradually consolidated into a mass of great firmness. The reticulated walls of the Romans, having bricks with oblique surfaces, would at the present day be thought highly unphilosophical. Indeed they could not long have stood, had it not been for the great strength of their cement.

Modern brick walls are laid with great precision, and depend for firmness more upon their position than upon the strength of their cement. The bricks being laid in horizontal courses, and continually overlaying each other, or breaking joints, the whole mass is strongly interwoven, and bound together. When the bricks do not break joints, it is sometimes practised to insert thin pieces of iron between the tiers. Wooden walls, composed of timbers covered with boards, are a common, but more perishable kind. They require to be constantly covered with a coating of a foreign substance, as paint or plaster, to preserve them from spontaneous decomposition.

In some parts of France, and elsewhere, a kind of wall is made of earth, rendered compact by ramming it in moulds or cases. This method is called building in Pisé, and is much more durable than the nature of the material would lead us to suppose.

Walls of all kinds are greatly strengthened by angles and curves, also by projections, such as pilasters, chimneys, and buttresses. These projections serve to increase the breadth of the foundation, and are always to be made use of in large buildings, and in walls of considerable length.

Lintel.--The lintel, or beam, extends in a right line over a vacant space, from one column or wall to another. The strength of the lintel will be greater in proportion as its transverse vertical diameter exceeds the horizontal, the strength being always as the square of the depth. [See page 124.] The floor is the lateral continuation or connection of beams by means of a covering of boards.

Arch.--The arch is a transverse member of a building answering the same purpose as the lintel, but vastly exceeding it in strength. The arch, unlike the lintel, may consist of any number of constituent pieces, without impairing its strength. It is, however, necessary that all the pieces should possess a uniform shape, the shape of a portion of a wedge; and that the joints, formed by the contact of their surfaces, should point towards a common centre. In this case, no one portion of the arch can be displaced or forced inward; and the arch cannot be broken by any force which is not sufficient to crush the materials of which it is made. In arches made of common bricks, the sides of which are parallel, any one of the bricks might be forced inward, were it not for the adhesion of the cement. Any two of the bricks, however, constitute a wedge, by the disposition of their mortar, and cannot collectively be forced inward. An arch of the proper form, when complete, is rendered stronger, instead of weaker, by the pressure of a considerable weight, provided this pressure be uniform. While building, however, it requires to be supported by a centring of the shape of its internal surface, until it is complete. The upper stone of an arch is called the key-stone, but is not more essential than any other.

A brick arch has been erected without centring, by laying pieces of hoop iron between the courses, which serve to bind the whole strongly together.

In regard to the shape of the arch, its most simple form is that of the semicircle. [Pl. II. Fig. k.] It is, however, very frequently a smaller arc of a circle, and still more frequently a portion of an ellipse. The simplest theory of an arch supporting itself only, is that of Dr. Hooke. The arch, when it has only its own weight to bear, may be considered as the inversion of a chain, suspended at each end. The chain hangs in such a form, that the weight of each link or portion is held in equilibrium by the result of two forces acting at its extremities; and these forces, or tensions, are produced, the one by the weight of the portion of the chain below the link, the other by the same weight increased by that of the link itself, both of them acting originally in a vertical direction. Now, supposing the chain inverted, so as to constitute an arch of the same form and weight, the relative situations of the forces will be the same, only they will act in contrary directions, so that they are compounded in a similar manner, and balance each other, on the same conditions. The arch thus formed, is denominated a catenary arch. [Pl II. Fig. l.] In common cases it differs but little from a circular arch of the extent of about one third of a whole circle, and rising from the abutments with an obliquity of about thirty degrees from a perpendicular.

But though the catenary arch is the best form for supporting its own weight, and also all additional weight which presses in a vertical direction, it is not the best form to resist lateral pressure, or pressure like that of fluids, acting equally in all directions. Thus the arches of bridges and similar structures, when covered with loose stones and earth, are pressed sidewise, as well as vertically, in the same manner as if they supported a weight of fluid. In this case, it is necessary that the arch should arise more perpendicularly from the abutment, and that its general figure should be that of the longitudinal segment of an ellipse. [Pl. II. Fig. m.] In small arches in common buildings, where the disturbing force is not great, it is of little consequence what is the shape of the curve. The outlines may even be perfectly straight, as in the tier of bricks which we frequently see over a window. This is, strictly speaking, a real arch, provided the surfaces of the bricks tend towards a common centre. [Pl. II. Fig. s.] It is the weakest kind of arch, and a part of it is necessarily superfluous, since no greater portion can act in supporting a weight above it, than can be included between two curved or arched lines.

Besides the arches already mentioned, various others are in use. The acute or lancet arch, [Pl. II. Fig. o,] much used in Gothic architecture, is described usually from two centres outside the arch. It is a strong arch for supporting vertical pressure. The rampant arch [Fig. n] is one, in which the two ends spring from unequal heights. The horse-shoe or Moorish arch [Fig. p and q] is described from one or more centres placed above the base line. In this arch, the lower parts are in danger of being forced inward. The ogee arch [Fig. r] is concavo-convex, and therefore fit only for ornament.

In describing arches, the upper surface is called the extrados, and the inner, the intrados. The springing lines are those where the intrados meets the abutments, or supporting walls. The span is the distance from one springing line to the other. The wedge-shaped stones which form an arch, are sometimes called voussoirs, the uppermost being the keystone. [Pl. II. Fig. k.] The part of a pier from which an arch springs, is called the impost, and the curve formed by the upper side of the voussoirs, the archivolt.

Abutments.--It is necessary that the walls, abutments, and piers, on which arches are supported, should be so firm as to resist the lateral thrust, as well as vertical pressure, of the arch. It will at once be seen that the lateral or sideway pressure of an arch is very considerable, when we recollect that every stone, or portion of the arch, is a wedge, a part of whose force acts to separate the abutments. For want of attention to this circumstance, important mistakes have been committed, the strength of buildings materially impaired, and their ruin accelerated. In some cases, the want of lateral firmness in the walls, is compensated by a bar of iron stretched across the span of the arch and connecting the abutments, like the tie beam of a roof. This is the case in the cathedral of Milan, and some other Gothic buildings.[A]

Arcade.--In an arcade, or continuation of arches, it is only necessary that the outer supports of the terminal arches should be strong enough to resist horizontal pressure. In the intermediate arches, the lateral force of each arch is counteracted by the opposing lateral force of the one contiguous to it. In bridges, however, where individual arches are liable to be destroyed by accident, it is desirable, that each of the piers should possess sufficient horizontal strength, to resist the lateral pressure of the adjoining arches.

Vault.--The vault is the lateral continuation of an arch, serving to cover an area, or passage, and bearing the same relation to the arch, that the wall does to the column. A simple vault is constructed on the principles of the arch, and distributes its pressure equally along the walls, or abutments. A complex or groined vault is made by two vaults intersecting each other; in which case, the pressure is thrown upon springing points, and is greatly increased at those points. The groined vault is common in Gothic architecture.

Dome.--The dome, sometimes called cupola, is a concave covering to a building, or part of it, and may be either a segment of a sphere, of a spheroid, or of any similar figure. When built of stone, it is a very strong kind of structure, even more so than the arch, since the tendency of each part to fall, is counteracted, not only by those above and below it, but also by those on each side. It is only necessary that the constituent pieces should have a common form, and that this form should be somewhat like the frustum of a pyramid, so that when placed in its situation, its four angles may point toward the centre, or axis, of the dome. During the erection of a dome, it is not necessary that it should be supported by a centring, until complete, as is done in the arch. Each circle of stones, when laid, is capable of supporting itself, without aid from those above it. It follows, that the dome may be left open at top, without a key-stone, and yet be perfectly secure, in this respect, being the reverse of the arch. The dome of the Pantheon, at Rome, has been always open at top, and yet has stood unimpaired for nearly two thousand years. The upper circle of stones, though apparently the weakest, is nevertheless often made to support the additional weight of a lantern or tower above it. In several of the largest cathedrals, there are two domes, one within the other, which contribute their joint support to the lantern which rests upon the top. In these buildings, the dome rests upon a circular wall, which is supported in its turn by arches upon massive pillars or piers. This construction is called building upon pendentives, and gives open space and room for passage, beneath the dome.

[A] Cadell's Journey through Carniola and Italy, vol. ii. p. 77.

The remarks which have been made in regard to the abutments of the arch, apply equally to the walls immediately supporting a dome. They must be of sufficient thickness and solidity to resist the lateral pressure of the dome, which is very great. The walls of the Roman Pantheon are of great depth and solidity. In order that a dome in itself should be perfectly secure, its lower parts must not be too nearly vertical, since in this case, they partake of the nature of perpendicular walls, and are acted upon by the spreading force of the parts above them. The dome of St. Paul's church, in London, and some others of similar construction, are bound with chains or hoops of iron, to prevent them from spreading at bottom. Domes which are made of wood, depend in part for their strength, on their internal carpentry. The Halle du Bled, in Paris, had, originally, a wooden dome more than two hundred feet in diameter, and only one foot in thickness. This has since been replaced by a dome of iron.

Plate II.--In this plate is given a comparative view in outline of some of the most remarkable domes in ancient and modern buildings, together with the edifices to which they belong, likewise various other structures reduced to the same scale.

The highest dome, [No. 3,] is that of St. Peter's church at Rome, generally considered the most splendid building in the world, and one of the largest in size. This edifice was a century in building, from about 1510 to 1610. It was begun by Bramante, and finished by Michael Angelo and Vignola. The dome is of an ellipsoidal form, solid at bottom, but divided into two thin, concentric domes at top, between which is the stair leading to the lantern. The whole height from the ground to the cross at top, is about four hundred and seventy feet. The base of the dome rests upon arches, supported by massive stone piers. Within the last century, some fissures of dangerous appearance were discovered in this dome; to remedy which, it was surrounded with iron chains by the artist Zabaglia.

The next dome in height, [No. 4,] is that of the church of St. Maria del Fiore, at Florence. Its vertical section is an elongated ellipsoid, its horizontal section octagonal. This church is about three hundred and eighty feet high, and was built between 1298 and 1472. The dome was erected by Bruneleschi, one of the earliest revivers of antique architecture.

St. Paul's cathedral, London, [No. 5,] was erected by Sir Christopher Wren, between 1685 and 1710. It has two domes at different heights, the inner being made of brick, and the outer of wood. Between the two, is a hollow, truncated cone of brick-work, which furnishes the support of the lantern at top. The outline of the dome is somewhat more than a semicircle, and is prevented from spreading at bottom, by a strong iron hoop.

The church of St. Genevieve, in Paris, [No. 6,] which, during the absence of the Bourbon family, was called the Pantheon, was begun by Soufflot, in 1757. This edifice has been threatened with ruin, in consequence of the piers, which support the dome, being made too small for the nature of the material, and the superincumbent weight. It became necessary to replace a part of the stones which were crushed, and to increase the amount of support, to obtain present security.

The mosque of St. Sophia, at Constantinople, [No. 7,] presents a specimen of the kind of dome used by the ancients, which was more flat than any of the preceding examples, and was usually a small segment of a sphere. This edifice was erected during the reign of Justinian, in the sixth century. Owing to the want of sufficient solidity in the supporting wall, the dome fell down at two successive times, and the architect was under the necessity of filling up the subjacent arcades, and of building large buttresses on the outside of the wall, to resist the pressure, and give to the dome eventual stability. The span of this dome is one hundred and twelve feet.

The Pantheon, at Rome, [No. 8,] is probably the oldest dome now standing, and is one of the best constructed. Its outer and inner surfaces are of different curvatures, so that the thickness increases downward, the inner surface being a hemisphere. The walls of this edifice are of great solidity, and to this circumstance the security of the superstructure is in part owing. This dome is open at the top. It was built by Agrippa, in the reign of Augustus Caesar. A more perfect view of the Pantheon is given in Fig. 45, on p. 286.

The outline of St. Mark's church, at Venice, which has several domes; that of the front of the Parthenon, at Athens, which shows the lowness of the Grecian pediment; that of the restored temple of Vesta, at Tivoli; and, lastly, that of the small Ionic temple which stood upon the Ilissus, are added merely to give an idea of their comparative size. The column erected to the memory of the emperor Trajan, also one of the obelisks brought from Egypt by the ancient Romans, are introduced upon the same scale.

No. 1, in the same plate, represents the outline of the largest of the Egyptian Pyramids, respecting the dimensions of which, travellers vary greatly in their accounts. One of the more moderate of their estimates is here taken, which makes the height a little less than five hundred feet.

No. 2, shows the length and height of the Colosseum, at Rome, a vast elliptical amphitheatre, which fifteen thousand men were occupied ten years in completing. It was built in the reign of Vespasian and Titus, and its walls are standing at the present day.

No. 15, represents the celebrated leaning tower of Pisa. The several stories of this structure are supported by arcades upon columns, in the Greco-gothic style. The height of the whole is one hundred and eighty feet. This tower leans over about fourteen feet from a perpendicular. The view here taken of it, does not represent its greatest inclination. Whether the obliquity was the effect of design, or of the settling of the foundation on one side, is a point upon which writers are not agreed. It was built in the twelfth century.

No. 16, is the steeple of the Gothic cathedral, at Strasburg. It is among the highest steeples in Europe, and is introduced to show its comparative elevation. No. 17, is the centre steeple of the Duomo or Cathedral of Milan, about three hundred and fifty feet high. This edifice is of white marble. Its general character is Gothic, intermixed with details in the later Roman style.

The proportions of most of the foregoing buildings are taken from Durand, who has reduced them to a scale. The same scale applies to the other architectural plates in this volume, with the exception of perspective representations, in which more than one side is seen.

The outlines of several American edifices, reduced to the same scale, are added in this plate, for the convenience of comparison. No. 18, is that of the Capitol, at Washington, built of freestone, the length of which is three hundred and fifty feet, the height of the front seventy feet, and the height of the centre dome one hundred and forty-eight feet. No. 19, is the City Hall, at New York, built chiefly of marble; its length two hundred and twenty feet, and the height of the statue at top, one hundred and twenty feet. No. 20, is the State House, in Boston, one hundred and seventy-three feet in length, built of brick, and painted. No. 21, is the Bank of the United States, at Philadelphia, a marble building, having its front eighty-six feet wide, copied in most respects from the Parthenon at Athens. No. 22, the monument erected at Baltimore, in commemoration of the battle and victory at that place. Height about fifty-five feet.

Roof.--The roof is the most common and cheap method of covering buildings, to protect them from rain and other effects of the weather. It is sometimes flat, but more frequently oblique in its shape. The flat or platform roof is the least advantageous for shedding rain, and is seldom used in northern countries. The pent roof, consisting of two oblique sides meeting at top, is the most common form. [Pl. II. Fig. w.] These roofs are made steepest in cold climates, where they are liable to be loaded with snow. Where the four sides of the roof are all oblique, it is denominated a hipped roof, [Fig. x;] and where there are two portions to the roof, of different obliquity, it is a curb, or mansard roof. [Fig. y.] In modern times, roofs are made almost exclusively of wood, though frequently covered with incombustible materials. The internal structure or carpentry of roofs, is a subject of considerable mechanical contrivance. The roof is supported by rafters, which abut on the walls on each side, like the extremities of an arch. If no other timbers existed, except the rafters, they would exert a strong lateral pressure on the walls, tending to separate and overthrow them.[A] To counteract this lateral force, a tie beam, as it is called, extends across, receiving the ends of the rafters, and protecting the wall from their horizontal thrust. To prevent the tie beam from sagging} or bending downward with its own weight, a king post is erected from this beam, to the upper angle of the rafters, serving to connect the whole, and to suspend the weight of the beam. This is called trussing. Queen posts are sometimes added, parallel to the king post, in large roofs; also various other connecting timbers. In Gothic buildings, where the vaults do not admit of the use of a tie beam, the rafters are prevented from spreading, as in an arch, by the strength of the buttresses.

[A] The largest roof that has hitherto been built, is supposed to have been that of the riding house, at Moscow. Its span was two hundred and thirty-five feet, and the slope of the roof, about nineteen degrees. The principal support of this immense truss, consisted in an arch of timber in three thicknesses, indented together, and strapped and bolted with iron. The principal rafters and tie beams, were supported by several vertical pieces, notched to this arch, and the whole stiffened by diagonal braces.--Tredgold's Carpentry, p. 87.

In comparing the lateral pressure of a high roof, with that of a low one, the length of the tie beam being the same, it will be seen that a high roof, from its containing most materials, may produce the greatest pressure, as far as weight is concerned. On the other hand, if the weight of both be equal, then the low roof will exert the greater pressure, and this will increase in proportion to the distance of the point at which perpendiculars drawn from the end of each rafter, would meet.

In roofs, as well as in wooden domes, and bridges, the materials are subjected to an internal strain, to resist which the cohesive strength of the material is relied on. On this account, beams should, when possible, be of one piece. Where this cannot be effected, two or more beams are connected together by splicing. Spliced beams are never so strong as whole ones, yet they may be made to approach the same strength, by affixing lateral pieces, or by making the ends overlay each other, and connecting them with bolts and straps of iron. The tendency to separate is also resisted, by letting the two pieces into each other, by the process called scarfing. Mortises, intended to truss or suspend one piece by another, should be formed upon similar principles.

Roofs in this country, after being boarded, receive a secondary covering of shingles. When intended to be incombustible, they are covered with slates or earthen tiles or with sheets of lead, copper or tinned iron. Slates are preferable to tiles, being lighter, and absorbing less moisture. Metallic sheets are chiefly used for flat roofs, wooden domes, and curved and angular surfaces, which require a flexible material to cover them, or have not a sufficient pitch to shed the rain from slates or shingles. Various artificial compositions are occasionally used to cover roofs, the most common of which are mixtures of tar with lime, and sometimes with sand and gravel.

Styles of Building.--The architecture of different countries has been characterized by peculiarities in external form, and in modes of construction. These peculiarities, among ancient nations, were so distinct, that their structures may be identified even in the state of ruins; and the origin and era of each may be conjectured with tolerable accuracy. Before we proceed to describe architectural objects, it is necessary to explain certain terms, which are used to denote their different constituent portions. The architectural orders will be spoken of under the heads of the Grecian and Roman styles, but their component parts ought previously to be understood.

Definitions.--The front or façade of a building, made after the ancient models, or any portion of it, may present three parts, occupying different heights.

The pedestal is the lower part, usually supporting a column. The single pedestal is wanting in most antique structures, and its place supplied by a stylobate. The stylobate is either a platform with steps, or a continuous pedestal, supporting a row of columns. The lower part of a finished pedestal is called the plinth,[A] the middle part is the die, and the upper part the cornice of the pedestal, or surbase.

The column, is the middle part, situated upon the pedestal or stylobate. It is commonly detached from the wall, but is sometimes buried in it for half its diameter, and is then said to be engaged. Pilasters are square or flat columns, attached to walls. The lower part of a column, when distinct, is called the base; the middle, or longest part, is the shaft, and the upper, or ornamented part, is the capital. The height of columns is measured in diameters of the column itself, taken always at the base.

[A] The name plinth, in its general sense, is applied to any square projecting basis, such as those at the bottom of walls, and under the base of columns.

The entablature, is the horizontal, continuous portion, which rests upon the top of a row of columns. The lower part of the entablature is called the architrave, or epistylium. The middle part is the frieze, which, from its usually containing sculpture, was called zophorus by the ancients. The upper, or projecting part, is the cornice.

A pediment, is the triangular face, produced by the extremity of a roof. The middle, or flat portion, enclosed by the cornice of the pediment, is called the tympanum. Pedestals for statues, erected on the summit and extremities of a pediment, are called acroteria. See temple of Antoninus and Faustina. An attic, is an upper part of a building, terminated at top by a horizontal line, instead of a pediment.

The different mouldings in architecture are described from their sections, or from the profile which they present, when cut across. Of these, the torus [Plate II. a] is a convex moulding, the section of which is a semicircle, or nearly so. The astragal, [b,] is like the torus, but smaller. The ovolo, [c,] is convex, but its outline is only the quarter of a circle. The echinus, [d,] resembles the ovolo, but its outline is spiral, not circular. The scotia, [e,] is a deep, concave moulding. The cavetto, [f,] is also concave, and occupying but a quarter of a circle. The cymatium, [g,] is an undulated moulding, of which the upper part is concave, and the lower convex. The ogee talon, [h,] is an inverted cymatium. The fillet, [i,] is a small, square or flat moulding.[A]

Measures.--In architectural measurement, a diameter means the width of a column at the base. A module is half a diameter. A minute is a sixtieth part of a diameter.

Drawings.--In representing edifices by drawings, architects make use of the plan, elevation, section, and perspective. The plan is a map, or design, of a horizontal surface, showing the ichnographic projection, or groundwork, with the relative position of walls, columns, doors, &c.[B] The elevation is the orthographic projection of a front, or vertical surface; this being represented, not as it is actually seen in perspective, but as it would appear if seen from an infinite distance. The section shows the interior of a building, supposing the part in front of an intersecting plane to be removed. The perspective shows the building as it actually appears to the eye, subject to the laws of scenographic perspective. The three former are used by architects, for purposes of admeasurement; the latter is used also by painters, and is capable of bringing more than one side into the same view, as the eye actually perceives them.

[A] By a singular mixture of derivations, the Greek, Latin, Italian, French, and English languages are laid under contribution for the technical terms of Architecture.

[B] See various plans of temples, on pages 275, 276, 277.

Restorations.--As the most approved features in modern architecture are derived from buildings which are more or less ancient, and as many of these buildings are now in too dilapidated a state to be easily copied, recourse is had to such imitative restorations in drawings and models, as can be made out from the fragments and ruins which remain. In consequence of the known simplicity and regularity of most antique edifices, the task of restoration is less difficult than might be supposed. The groundwork, which is commonly extant, shows the length and breadth of the building, with the position of its walls, doors, and columns. A single column, whether standing or falling, and a fragment of the entablature, furnish data from which the remainder of the colonnade, and the height of the main body, can be made out. A single stone from the cornice of the pediment, is often sufficient to give the angle of inclination, and consequently the height of the roof. In this way, beautiful restorations are obtained of structures, when in so ruinous a state, as scarcely to have left one stone upon another.

EGYPTIAN STYLE.

In ancient Egypt, a style of building prevailed, more massive and substantial than any which has succeeded it. The elementary features of Egyptian architecture, were chiefly as follows. 1. Their walls were of great thickness, and sloping on the outside. This feature is supposed to have been derived from the mud walls, mounds, and caverns of their ancestors. 2. The roofs and covered ways were flat, or without pediments, and composed of blocks of stone, reaching from one wall or column to another. The principle of the arch, although known to them, was seldom employed by them. 3. Their columns were numerous, close, short, and very large, being sometimes ten or twelve feet in diameter. They were generally without bases, and had a great variety of capitals, from a simple square block, ornamented with hieroglyphics, or faces, to an elaborate composition of palm leaves not unlike the Corinthian capital. 4. They used a sort of concave entablature, or cornice, composed of vertical flutings, or leaves, and a winged globe in the centre. 5. Pyramids, well known for their prodigious size, and obelisks composed of a single stone, often exceeding seventy feet in height, are structures peculiarly Egyptian. 6. Statues of enormous size, sphinxes carved in stone, and sculptures in outline of fabulous deities and animals, with innumerable hieroglyphics, are the decorative objects which belong to this style of architecture.

The subjoined figure (23) represents an ancient Egyptian temple at Essenay.

An idea may be formed from the plates of travellers, of the general plan of the great Egyptian temples. 1. An avenue of sphinxes. 2. Two colossal figures on each side of a gateway, formed by immense towers of truncated pyramids, with overhanging cornices. 3. This gateway led into a court full of columns, and chambers round the walls. 4. Passing across this, the visiter comes to other courts, likewise full of columns, through gateways, ornamented with colossal figures and obelisks. 5. In the centre was the sanctuary, absolutely without light. These sanctuaries often consisted of a single excavated block. They are called Monolithic temples, and one has been described by the ancients, at the temple of Latona, as forty cubits broad in front, carved out of one entire stone, and roofed by another. Semiramis is said to have brought from the mountains of Arabia a rock twenty cubits broad, and one hundred and fifty long. The Monolithic temple, engraved by Denon, is a mere upright parallelogram, with an aperture in the side. Little private sacella, or chapels, were likewise annexed to the larger Egyptian temples.

The architecture of the ancient Hindoos, appears to have been derived from the same original ideas as the Egyptian. The most remarkable relics of this people, are their subterraneous temples, of vast size and elaborate workmanship, carved out of the solid rock, at Elephanta, Ellora, and Salsette.

THE CHINESE STYLE.

The ancient Tartars, and wandering shepherds of Asia, appear to have lived from time immemorial in tents, a kind of habitation adapted to their erratic life. The Chinese have made the tent the elementary feature of their architecture; and of their style any one may form an idea, by inspecting the figures which are depicted upon common china ware. Chinese roofs are concave on the upper side, as if made of canvass instead of wood. A Chinese portico is not unlike the awnings spread over our shop windows in summer time. The verandah, sometimes copied in dwellinghouses here, is a structure of this sort. The Chinese towers and pagodas, have concave roofs, like awnings, projecting over their several stories. The lightness of the style used by the Chinese, leads them to build with wood, sometimes with brick, and seldom with stone. The following figure (24) represents the octagonal pagoda of Sinkicien, in China.

THE GRECIAN STYLE.

Grecian achitecture, from which have been derived the most splendid structures of later ages, has its origin in the wooden hut or cabin, formed of posts set in the earth, and covered with transverse poles and rafters. Its beginnings were very simple, being little more than imitations, in stone, of the original posts and beams. By degrees these were modified and decorated, so as to give rise to the distinction of what are now called the orders of architecture.

Orders of Architecture

By the architectural orders, are understood certain modes of proportioning and decorating the column and its entablature. They were in use during the best days of Greece and Rome, for a period of six or seven centuries. They were lost sight of in the dark ages, and revived again by the Italians at the time of the restoration of letters. The Greeks had three orders, called the Doric, Ionic and Corinthian. These were adopted and modified by the Romans, who also added two others, called the Tuscan and Composite.

Doric Order.--The Doric is the earliest and most massive order of the Greeks. It is known by its large columns with plain capitals, its triglyphs resembling the ends of beams, and its mutules corresponding to those of rafters. The column, in the examples at Athens, is about six diameters in height. In the older examples, as those at Paestum, it is but four or five. The shaft had no base, but stood directly on the stylobate. It had twenty flutings, which were superficial, and separated by angular edges. The perpendicular outline was nearly straight. The Doric capital was plain, being formed of a few annulets, or rings, a large echinus, and a flat stone at top called the abacus. The architrave was plain; the frieze was intersected by oblong projections called triglyphs, divided into three parts by vertical furrows, and ornamented beneath, by guttae, or drops. The spaces between the triglyphs were called metopes, and commonly contained sculptures. The sculptures representing Centaurs and Lapithae, carried by Lord Elgin to London, were metopes of the Parthenon or temple of Minerva, at Athens. The cornice of the Doric order consisted of a few large mouldings, having on their under side a series of square, sloping projections, resembling the ends of rafters, and called mutules. These were placed over both triglyphs and metopes, and were ornamented, on their under side, with circular guttoe. The best specimens of the Doric order, are found in the Parthenon, the Propylaea, and the Temple of Theseus, at Athens. [Figs. 33, 34, 35, 36, 37, 38.]

Ionic Order.--The Ionic is a lighter order than the Doric, its column being eight or nine diameters in height. It had a base often composed of a torus, a scotia, and a second torus, with intervening fillets. This is called the Attic base. [Fig. 70.] Others were used in different parts of Greece. The shaft had twenty-four, or more, flutings, which were narrow, as deep as a semicircle, and separated by a fillet or square edge. The capital of this order consisted of two parallel double scrolls, called volutes, occupying opposite sides, and supporting an abacus, which was nearly square, but moulded at its edges. These volutes have been considered as copied from ringlets of hair, or perhaps from the horns of Jupiter Ammon. When a column made the angle of an edifice, its volutes were placed, not upon opposite, but on contiguous sides; each fronting outward. In this case, the volutes interfered with each other at the corner, and were obliged to assume a diagonal direction. The Ionic entablature consisted of an architrave and frieze, which were continuous or unbroken, and a cornice of various successive mouldings, at the lower part of which was often a row of dentels or square teeth. The examples at Athens, of the Ionic order, are the temple of Erectheus, and the temple on the Ilissus, which was standing in Stuart's time, seventy years since, but is now extinct. [Figs. 70, 25, 40, 41, 42.]

Corinthian Order.--The Corinthian was the lightest and most decorated of the Grecian orders. Its base resembled that of the Ionic, but was more complicated. The shaft was often ten diameters in height, and was fluted like the Ionic. The capital was shaped like an inverted bell, and covered on the outside with two rows of leaves of the plant acanthus,[A] above which were eight pairs of small volutes. Its abacus was moulded and concave on its sides, and truncated at the corners, with a flower on the centre of each side. The entablature of the Corinthian order, resembled that of the Ionic, but was more complicated and ornamented, and had, under the cornice, a row of large oblong projections, bearing a leaf or scroll on their under side, and called modillions. No vestiges of this order are now found in the remains of Corinth, and the most legitimate example at Athens, is in the choragic monument of Lysicrates, [Fig. 43.] The Corinthian order was much employed in the subsequent structures of Rome, and its colonies, [Figs. 71, 45, 46, 47, &c.]

Caryatides.--The Greeks sometimes departed so far from the strict use of the orders, as to introduce statues, in the place of columns, to support the entablature. Statues of slaves, heroes, and gods, appear to have been employed occasionally for this purpose. The principal specimen of this kind of architecture, which remains, is in a portico, called Pandroseum, attached to the temple of Erectheus, at Athens, in which statues of Carian females, called Caryatides, are substituted for columns. [Fig. 41.] One of these statues has been carried to London.

Grecian Temple.--The most remarkable public edifices of the Greeks, were their temples. These, being intended as places of resort for the priests, rather than for the convening of assemblies within, were in general obscurely lighted. Their form was commonly that of an oblong square, having a colonnade without, and a walled cell within. The cell was usually without windows, receiving its light only from a door at the end, and sometimes from an opening in the roof. The part of the colonnade which formed the front portico, was called the pronaos, and that which formed the back part, the posticus. The colonnade was subject to great variety in the number and disposition of its columns, from which Vitruvius has described seven different species of temples. These were, 1. The temple with antae. In this, the front was composed of pilasters, called antae, on the sides, and two columns in the middle.

[A] The origin of the Corinthian capital has been ascribed to the sculptor Calliniiichus, who is said to have copied it from a basket accidentally enveloped in leaves of acanthus. A more probable supposition traces its origin to some of the Egyptian capitals, which it certainly resembles.

2. The Prostyle. This had a row of columns at one end only.

3. The Amphiprostyle, having a row of columns at each end.

4. The Peripteral temple. This was surrounded by a single row of columns, having six in front, and in rear, and eleven, counting the angular columns, on each side.

5. The Dipteral, with a double row of columns all round the cell, the front consisting of eight.

6. The Pseudo-dipteral differs from the dipteral, in having a single row of columns on the sides, at the same distance from the cell, as if the temple had been dipteral.

7. The Hypaethral temple had the centre of its roof open to the sky. It was colonnaded without, like the dipteral, but had ten columns in front. It had also an internal colonnade, called peristyle, on both sides of the open space, and composed of two stories or colonnades, one above the other.

Temples, especially small ones, were sometimes made of a circular form. When these were wholly open, or without a cell, they were called Monopteral temples. When there was a circular cell within the colonnade, they were called Peripteral.[A]

Grecian Theatre.--The theatre of the Greeks, which was afterwards copied by the Romans, was built in the form of a horse-shoe, being semicircular on one side, and square on the other. The semicircular part, which contained the audience, was filled with concentric seats, ascending from the centre, to the outside. In the middle, or bottom, was a semicircular floor called the orchestra. The opposite, or square part, contained the actors. Within this was erected, in front of the audience, a wall ornamented with columns and sculpture, called the scena. The stage, or floor, between this part and the orchestra, was called the proscenium. Upon this floor was often erected a movable wooden stage, called, by the Romans, pulpitum. The ancient theatre was open to the sky, but a temporary awning was erected to shelter the audience from the sun and rain.

Remarks.--Grecian architecture is considered to have been in its greatest perfection in the age of Pericles and Phidias. The sculpture of this period, is admitted to have been superior to that of any other age; and although architecture is a more arbitrary art than sculpture, yet it is natural to conclude, that the state of tilings which gave birth to excellence in the one, must have produced a corresponding power of conceiving sublimity and beauty in the other. Grecian architecture was, in general, distinguished by simplicity of structure, fewness of parts, absence of arches, lowness of pediments and roofs, and by decorative curves, the outline of which was a spiral line, or conic section, and not a circular arc, as afterwards adopted by the Romans.

[A] The intercolumniation, or distance between the columns, according to Vitruvius, was differently arranged under the following names. In the pycnostyle, the columns were a diameter and a half apart. In the systyle they were two diameters apart. In the diastyle, three. In the araeostyle, more than three, In the eustyle, two and a quarter.

The following drawings give a front view of various Grecian edifices, the remains of which are extant at the present day. The limits of the page permit only the front elevation to be given, which, in the oblong Grecian temples, was the end of the building.

Fig. 33, represents the principle temple at Paestum, in Italy. At this place are now standing, the walls and colonnades of three temples, built in the ancient Doric style, and undoubtedly erected by a Grecian colony in that country. The characters of this early Doric, are short and heavy columns, much diminished upwards, large capitals, and a massive entablature, nearly half as high as the columns. The outline of the columns in this building is straight, or without entasis. The temple appears to have been hypaethral, though the number of columns is less than in the rule prescribed by Vitruvius.

Fig. 34, is the Temple of Concord, commonly so called, at Agrigentum, now Girgenti, in Sicily. It is erected in the massive style of the older Doric, on a stylobate of four steps, and, with the exception of the roof, is in a state of good preservation at the present day. Other Doric ruins are found in the same place, also at Segesta, Selinus, and other parts of Sicily. Views of these structures are given in Wilkins's Magna Graecia.

Fig. 35, is the Temple of Theseus, at Athens, situated in the lower part of that city, some way from the Acropolis. It is the most perfectly preserved of any of the Athenian edifices, its columns and walls having suffered scarcely any dilapidation. At the top of its stone platform, or stylobate, it measures one hundred and four feet in length, by forty-five in breadth, and has six columns on each front, with thirteen on each side, counting those at the angles. The temple of Theseus was erected by Cimon, the son of Miltiades, about four hundred and fifty years before Christ. The sculptures upon the frieze of this building are supposed, by Stuart and others, to refer to the exploits of Theseus, but according to Mr. Wilkins,[A] they represent the labors of Hercules.

Fig. 36, is the Propylaea, at Athens, a structure of much beauty, which commanded the entrance to the Acropolis, or citadel. Besides a portico of six Doric columns on each front, it had an Ionic colonnade within, and a separate quadrangular building attached to each side. Before the entrance, are two large pedestals, supposed to have supported equestrian statues. The Propylaea was ascended by steps at different stages, and had also an inclined plane for carriages. This building was erected in the time of Pericles, and is now in a ruinous state, a great portion of what remains being hidden by the walls of the Turks. Fig. 37, is a transverse section of the Propylaea, made at right angles with the former view, and showing the different ascents.

[A] Topography and Buildings of Athens, 8vo. 1816.

Fig. 38. is the façade of the Parthenon, or temple of Minerva, situated on the summit of the Acropolis, at Athens. This building is now considered the best model for the Doric order, and no edifice, ancient or modern, commands such general applause at the present day. It was built by the architect Ictinus, during the administration of Pericles, about four hundred and forty years before Christ. Its decorative sculptures are supposed to have been executed under the direction of Phidias. The platform or stylobate, consists of three steps, the uppermost of which is two hundred and twenty seven feet in length, and one hundred and one in breadth. The number of columns is eight in the portico of each front, and seventeen on each flank, besides which there is an inner row of six columns at each end of the cell. The proportional height of the columns is five diameters and thirty-three minutes, and they diminish thirteen minutes in diameter, from bottom to top. The sculptures on the frieze represent the combats of the Centaurs and Lapithæ. Those on the eastern pediment, represented the fabulous birth of Minerva; and those on the western, the contests between that goddess and Neptune, for the right of presiding over the city. When Athens was visited by Wheler, in 1676, the Parthenon remained entire, with the exception of its roof. But during the siege of the city by the Venetians, in 1687, a shell which exploded in the midst of the cell, destroyed the whole central part of the wall, together with nineteen of the columns. Most of the sculpture of both pediments has also disappeared.

Fig. 39, is the choragic monument of Thrasyllus, situated without the Acropolis, and constituting the front of a grotto. It is not, strictly speaking, of any architectural order, but departs from the Doric, in having a row of circular wreaths, instead of triglyphs, and a continuous row of guttae at the bottom of the frieze.

Fig. 40, is the small Ionic amphiprostyle temple on the banks of the Ilissus, which was standing in Stuart's time, but has now wholly disappeared. The delineations obtained from this building by Stuart, have since furnished the most popular models of the Ionic order.

Fig. 41, is the Erectheum, an Ionic building, much admired, in the Acropolis, at Athens. It comprises two temples, one dedicated to Minerva Polias, the other to the nymph Pandrosus. The smaller portico of the Pandroseum, is remarkable for a row of Caryatides, or female statues, which perform the office of columns in supporting the entablature.[A] Fig. 25, is an Ionic capital from the temple on the Ilissus. Those of the temple of Minerva Polias were similar in the general form of the volutes, but had also an ornamented neck above the flutings.

Fig. 42, represents the façade of the Temple of Apollo Didymaeus, near Miletus. It was among the most celebrated Grecian structures. It was termed by Strabo, the greatest of all temples, and was ranked by Vitruvius, with that of Diana, at Ephesus. Although few of its columns are now standing, the ruins give evidence of its original size and magnificence. It appears to have been a dipteral temple, surrounded with a double row of columns, triple in front, and in all one hundred and twelve. Views of this building are given in the Ionian antiquities, and in the Voyage Pittoresque of Choiseul Gouffier.

[A] One of these statues was carried off by Lord Elgin, and is placed with other Athenian marbles in the British Museum. Stuart makes this building to consist of three temples, viz. those of Erecthens, Minerva Polias, and Pandrosus. Mr. Wilkins divides it into two.

Fig. 43 is the choragic monument of Lysicrates, at Athens, sometimes improperly called the Lantern of Demosthenes. This elegant little structure has a circular ornamented roof of one stone, and six Corinthian columns engaged in a circular wall, the whole supported on a square basis. It is now half inclosed in a modern convent.

Fig. 44, is the octagon tower, at Athens, commonly called the Tower of Ike Winds, from the emblematic sculptures on its sides. Its sides are marked with lines, for indicating the hour of the day by the shadows of gnomons.

ROMAN STYLE.

Roman architecture had its origin in copies of the Greek models. All the Grecian orders were introduced into Rome, and variously modified. Their number was augmented by the addition of two new orders, the Tuscan and the Composite.

Tuscan Order.--This order, derived from the ancient Etruscans, is not unlike the Doric deprived of its triglyphs and mutules. It had a simple base containing one torus. Its column was seven diameters in height, with an astragal below the capital. Its entablature, somewhat like the Ionic, consisted of plain, running surfaces. There is no vestige of this order among ancient ruins, and the modern examples of it are taken from the descriptions of Vitruvius. [Fig. 67.]

Roman Doric.--The Romans modified the Doric order by increasing the height of its column to eight diameters. Instead of the echinus which formed the Grecian capital, they employed the ovolo, with an astragal and neck below it. They placed triglyphs over the centre of columns, not at the corners, and used horizontal mutules, or introduced foreign ornaments in their stead. The theatre of Marcellus has examples of the Roman Doric. [Fig. 69.]

Roman Ionic.--The Romans diminished the size of the volutes in the Ionic order. They also introduced a kind of Ionic capital in which there were four pairs of diagonal volutes, instead of two pairs of parallel ones. This they usually added to parts of some other capital, but at the present day it is often used alone, under the name of modern Ionic.

Composite Order.--This fifth order was made by the Romans out of the Corinthian, simply by combining its capital with that of the diagonal, or modern Ionic. [Fig. 72.] Its best example is found in the arch of Titus. The favorite order, however, in Rome and its colonies, was the Corinthian, and it is this order which prevails among the ruins, not only of Rome, but of Nismes, Pola, Palmyra, and Balbec.

Roman Structures.--The temples of the Romans, sometimes resembled those of the Greeks, but often differed from them. The Pantheon, which is the most perfectly preserved temple of the Augustan age, is a circular building, lighted only from an aperture in the dome, and having a Corinthian portico in front. The amphitheatre differed from the theatre, in being a complete circular, or rather elliptical building, filled on all sides with ascending seats for spectators, and leaving only the central space, called the arena, for the combatants and public shows. The Colosseum is a stupendous structure of this kind. The aqueducts were stone canals, supported on massive arcades, and conveying large streams of water, for the supply of cities. The triumphal arches were commonly solid oblong structures, ornamented with sculptures, and open with lofty arches for passengers below. The basilica of the Romans, was a hall of justice, used also as an exchange, or place of meeting for merchants. It was lined on the inside with colonnades of two stories, or with two tiers of columns, one over the other. The earliest Christian churches at Rome, were sometimes called basilicae, from their possessing an internal colonnade. The monumental pillars, were towers in the shape of a column on a pedestal, bearing a statue on the summit, which was approached by a spiral staircase within. Sometimes, however, the column was solid. The thermae, or baths, were vast structures, in which multitudes of people could bathe at once. They were supplied with warm and cold water, and fitted up with numerous rooms, for purposes of exercise and recreation.

Remarks.--In several particulars, the Roman copies differed from the Greek models, on which they were founded. The stylobate, or substructure, among the Greeks, was usually a plain succession of platforms, constituting an equal access of steps, to all sides of the building. Among the Romans, it became an elevated structure, like a continued pedestal, accessible by steps only at one end. The spiral curve of the Greeks, was exchanged for the geometrical circular arc, as exemplified in the substitution of the ovolo for the echinus in the Doric capital. The changes in the orders, have been already mentioned. After the period of Hadrian, Roman architecture is considered to have been on the decline. Among the marks of a deteriorated style, introduced in the later periods, were columns with pedestals, columns supporting arches, convex friezes, entablatures squared so as to represent the continuation of the columns, pedestals for statues projecting from the sides of columns, niches covered with little pediments, &c.

The following buildings in the Roman style, are reduced to a scale, after Durand. They are all of the Corinthian order.

Fig. 45, is the Pantheon, already mentioned, of which the portico is of stone, while the body, or circular part covered by the dome, is of brick. The occurrence in this building, of two pediments, one above the other, is considered a defect, and probably indicates that the parts of the edifice were erected at different times. The entablature consists only of a cornice. In most other respects, the symmetry of this building is much admired.

Fig. 46, is the temple of Antoninus and Faustina, at Rome. The walls and columns are raised upon an elevated stylobate, and are approached by steps in front only, differing in this respect from the Grecian temples, which were accessible on all sides.

Fig. 47, is the Maison carrée at Nismes, in France, It is psuedo-peripteral, having its columns engaged in the wall, with the exception of ten, which form the portico in front. It has been lately discovered that this building which remains in excellent preservation, was erected to the memory of Caius and Lucius Caesar, sons of Agrippa, and grandsons of Augustus.[A]

Fig. 48, is the circular peripteral temple of Vesta, at Rome. The temple of Vesta, at Tivoli, differs from this, in having a raised stylobate. The dome, in both these buildings, is an imaginary restoration, made after the rules of Vitruvius. Messrs. Taylor and Cresy have given to the temple at Tivoli, a conical roof, like that of the monument of Lysicrates.

Fig. 49, is a temple at Pola, in Istria, dedicated to Rome and Augustus. At this place are many interesting antiquities, among which are an amphitheatre and triumphal arch.

Fig. 50, is the structure commonly called the Arch of Theseus, at Athens. It was erected probably by the Roman emperor Hadrian, to divide the new city from the old, and bears an inscription on each side, indicating that on one side is seen the city of Theseus, and on the other the city of Hadrian.

[A] The origin and date of this beautiful temple were unknown, until an artist, named Seguier, made out the inscription on the frieze, by connecting together the holes in which the nails were driven, that formerly confined bronze letters upon the wall

Fig. 51, is a sepulchre at Mylassa, in Asia Minor, apparently of Roman origin, and described in the Ionian antiquities. Its angular pillars are square, but the intermediate columns have a form very unusual in ancient or modern architecture, being compressed, so that a section of the shaft represents an ellipse. They are fluted for half their length.

Fig. 52, is the triumphal arch of Constantine, at Rome, which, with the exception of a part of its sculptures, is entire at the present day. This arch was built after the arts had begun to decline, and is constructed chiefly of materials taken from the arch of Trajan, erected two centuries before. Its columns stand upon separate, projecting pedestals, and have a part of the entablature squared upon the top of each.

Fig. 53, is the external portico of the Temple of the Sun, at Palmyra. The ruins of this city exceed in extent and magnificence anything else which remains of antiquity in Europe, or Asia. It is built in the Corinthian order, and in the later style of Roman architecture, characterized by niches in the walls at different heights, containing statues; by numerous small pediments and entablatures; also in some cases by statues supported on brackets, or pedestals projecting from the sides of columns. In this portico, an example occurs of double columns, a feature rarely met with, in antique architecture, but sometimes used by the moderns, upon an extensive scale.[A]

Fig. 54, is the circular temple at Balbec, a place distinguished by the magnificence and colossal size of its ruins. This temple is singular in the form of its outline, which is circular, with large concave recesses between all the columns, as shown more distinctly in the ground plan, Fig. 55, of the same building. In other respects it partakes of the later Roman style.

[A] To the regular duplicature of columns introduced in the colonnade of the Louvre, in Paris, Perrault has given the name of araeo-systile. See note, p.277.

Fig. 56, is the octagonal temple of Jupiter, forming part of the palace erected by the Roman emperor Diocletian, at Salona, now Spalatro, in Dalmatia, where its extensive ruins are still extant.

GRECO-GOTHIC STYLE.

After the dismemberment of the Roman empire, the arts degenerated so far, that a custom became prevalent of erecting new buildings with the fragments of old ones, which were dilapidated and torn down for the purpose. This gave rise to an irregular style of building, which continued to be imitated, especially in Italy, during the dark ages. It consisted of Grecian and Roman details, combined under new forms, and piled up into structures wholly unlike the antique originals. Hence the names Greco-gothic and Romanesque architecture have been given to it. It frequently contained arches upon columns, forming successive arcades, which were accumulated above each other to a great height. The effect was sometimes imposing. The cathedral and leaning tower, at Pisa, and the church of St. Mark, at Venice, are cited as the best specimens of this style. [Pl. II. No. 15, and Fig. 74.] The Saxon architecture, used anciently in England, has some things in common with this style.

SARACENIC STYLE.

The edifices erected by the Moors and Saracens in Spain, Egypt, and Turkey, are distinguished, among other things, by a peculiar form of the arch. This is a curve, constituting more than half of a circle, or ellipse. This construction of the arch, is unphilosophical, and comparatively insecure. A similar peculiarity exists in the domes of the oriental Mosques, which are sometimes large segments of a sphere, appearing as if inflated; and at other times concavo-convex in their outline, as in the mosque of Achmet, in Constantinople, represented in the figure which follows. [57.] It has a central dome, surrounded by four half domes, which cover vast recesses resembling niches. Its court is surrounded by a sort of cloister, covered by numerous small cupolas, and having minarets at the angles and sides. The minaret is a tall, slender tower, peculiar to Turkish architecture. A peculiar flowery decoration, called arabesque, is common m the Moorish buildings of Europe, and Africa. [Pl. II. Fig. p and q, Fig. 77.]

GOTHIC STYLE.

The Goths, who plundered Rome, had nothing to do with the invention of Gothic architecture. The name was introduced by Sir Christopher Wren, and others, as a term of reproach, to stigmatize the edifices of the middle ages, which departed from the purity of the antique models. The term was, at first, very extensive in its application, but it is now confined chiefly, to what may be called the modern Gothic,--the style of building cathedrals, churches, abbeys, &c. which was introduced in England six or eight centuries ago, and adopted, nearly at the same time, in France, Germany, and other parts of Europe. The Gothic style is peculiar and strongly marked. Its principle seems to have originated in the imitation of groves, and bowers, under which the Druids performed their sacred rites. Its characteristics, at sight, are, its pointed arches, its pinnacles and spires, its large buttresses, clustered pillars, vaulted roofs, profusion of ornaments, and the general predominance of the perpendicular over the horizontal.

Although the Gothic style of building was originated at a period, when the arts were less successfully cultivated than they were in the time of the Greeks, it has nevertheless given rise to some of the most lofty, the most highly decorated, and the most imposing structures now in existence.

Definitions.--As the common place for the display of Gothic architecture, has been in ecclesiastical edifices, it is necessary to understand the usual plan and construction of these buildings. A church or cathedral is commonly built in the form of a cross, having a tower, lantern, or spire, erected at the place of intersection. The part of the cross, situated toward the west, is called the nave. The opposite, or eastern part, is called the choir, and within this is the chancel. The transverse portion, forming the arms of the cross, is called the transept.

These are called buttresses, and they are rendered necessary to prevent the walls from spreading under the enormous weight of the roofs. [Figs. 59, and 60.] On the tops of the buttresses, and elsewhere, are slender pyramidal structures, or spires, called pinnacles. These are ornamented on their sides, with rows of projections, appearing like leaves or buds, which are named crockets. The summit, or upper edge of a wall, if straight, is called a parapet; if indented, a battlement. Gothic windows were commonly crowned with an acute arch. They were long and narrow, or if wide, were divided into perpendicular lights by mullions. The lateral spaces on the upper and outer side of the arch, are called spandrells; and the ornaments in the top, collectively taken, are the tracery. An oriel, or bay window, is a projecting window. A wheel, or rose window, is large and circular. A corbel, is a bracket or short projection from a wall, serving to sustain a statue, or the springing of an arch.

Gothic pillars or columns, are usually clustered, appearing as if a number were bound together. The single shafts thus connected, are called boltels. They are confined chiefly to the inside of buildings, and never support anything like an entablature. Their use is to aid in sustaining the vaults under the roof, which rest upon them at springing points. [Fig. 61]. Gothic vaults intersect each other, forming angles called groins. The parts which are thrown out of the perpendicular, to assist in forming them, are the pendemives. The ornamented edge of the groined vault, extending diagonally, like an arch, from one support to another, is called the ogyve. The gothic term gable, indicates the erect end of a roof, and answers to the Grecian pediment, but is more acute.

The Gothic style of building is more imposing, and more difficult to execute, than the Grecian. This is because the weight of its vaults and roofs is upheld at a great height, by supporters acting at single points, and apparently but barely sufficient to effect their object. Great mechanical skill is necessary, in balancing and sustaining the pressures; and architects at the present day, find it difficult to accomplish what was achieved by the builders of the middle ages.

Fig. 59, is a perspective view of York cathedral, one of the most admired specimens of Gothic architecture. It is built in the form of a cross, and has three towers, of which the two front ones are surmounted by pinnacles, and the central one by battlements. It was built between the years 1171 and 1426.

Fig. 60, is a Gothic exterior, from the wall of Westminster Abbey, showing the buttresses, which support the walls; also the short pinnacles and battlements. The slanting braces at top are called flying buttresses.

Fig. 61, is a Gothic interior, from the nave of York cathedral. It shows the clustered pillars, pointed arches, groined vaulting, and tracery, which belong to the Gothic style.

In the following figures, is presented a series of columns, with some of their entablatures, arches, &c., illustrative of the styles of building which have prevailed in different epochs, and countries. The first three figures are those of Egyptian columns, all serving to show the massiveness of structure which prevailed in the buildings of that nation. A great variety of these columns exist at the present day in Upper Egypt, particularly at Karnac and Luxor, the remains of ancient Thebes. Fig. 62, is from a tomb of Silsilis, and has an outline which is common among the Egyptian ruins.--Fig. 63, likewise a common form, has a capital composed of faces. Fig. 64, is a column from Komonbu. The idea of the Corinthian capital, seems to have been borrowed from Egyptian specimens of this kind. The column, Fig. 65, is from the great cave at Elephanta, near Bombay, one of the wonderful subterranean structures excavated by the ancient inhabitants of Hindostan out of solid rock. Fig. 66, is a column from the ruins of Persepolis. At this place, which contains the most remarkable relics of the ancient arts of Persia, the style of architecture partakes of the Egyptian and Hindoo characteristics, the columns, however, being more slender. Fig. 67, represents the Tuscan order, used by the ancient inhabitants of Etruria. Fig. 68, is the Grecian Doric, of the age of Pericles, at which time it is considered to have been in greatest perfection. Fig. 69, is the Roman Doric, represented with a base, after the Restorations of the moderns. Fig. 70, is the Grecian Ionic. The base represented in this figure, and the next, is called the Attic base.--Fig. 71, the Corinthian order. Fig. 72, the Composite order, in which the volutes are larger than in the Corinthian. The modern Ionic is taken from the upper part of this capital. The frieze is represented as convex, a feature which is considered peculiar to the later or declining period of Roman architecture. Fig. 73, is a combination of the column with a pedestal, and a squared portion of the entablature, usually attached to the main edifice, by one side. This peculiarity was introduced after the arts had begun to decline, and appears in many of the later Roman edifices. It has been absurdly imitated in more modern times, by making a squared entablature to constitute a portion of the column, and placing another entablature above it. Fig. 74, shows a mode of building with arches between the columns and the entablature. It is taken from the remains of Diocletian's palace at Spalatro, and seems to have given rise to the Greco-gothic style. Fig. 75, which also exhibits arches upon columns, is a specimen of Saxon architecture from the cathadral at Ely. Fig. 76, is a twisted column from a cloister belonging to St. Paul's church, without the walls, at Rome, rebuilt about the year 800. Columns of this sort occur in various Italian structures, but it is difficult to conceive of a form more at variance with architectural fitness or security. Fig. 77, Moorish double columns, arches, and arabesques, from the Alhambra, at Granada. In the same building, the true Saracenic, or horse-shoe arch, also occurs. Fig. 78, a Gothic pillar from Salisbury cathedral. Other Gothic forms are seen in Fig. 79, a Chinese column from the viceroy's palace, at Canton, Fig. 80, section of a reeded Egyptian column, Fig. 81, section of a fluted Doric column, Fig. 82, section of a fluted Ionic column, and Figs. 83, 84, and 85, sections of different Gothic columns.

Application.--In edifices erected at the present day, the Grecian and Gothic outlines are commonly employed, to the exclusion of the rest. In choosing between them, the fancy of the builder, more than any positive rule of fitness, must direct the decision. Modern dwellinghouses have necessarily a style of their own, as far as stories and apartments, and windows and chimneys, can give them one. No more of the styles of former ages can be applied to them, than what may be called the unessential and decorative parts. In general, the Grecian style, from its right angles and straight entablatures, is more convenient, and fits better with the distribution of our common edifices, than the pointed and irregular Gothic. The expense, also, is generally less, especially if anything like thorough and genuine Gothic is attempted; a thing, however, rarely undertaken, as yet, in this country. But the occasional introduction of the Gothic outline, and the partial employment of its ornaments, has undoubtedly an agreeable effect, both in public and private edifices; and we are indebted to it, among other things, for the spire, a structure exclusively Gothic, which, though often misplaced, has become an object of general approbation, and a pleasing landmark to our cities and villages.

WORKS OF REFERENCE.--WILKINS'S Translation of Vitruvius, 4to. 1817;--ELMES' Lectures on Architecture, 8vo. 1823;--STUART'S Antiquities of Athens, 4 vols. fol. 1762, &c.;--Antiquities of Ionia, by the DILETTANTI SOCIETY, 2 vols. fol. 1817-21;--Antiquities of Attica, by the same, fol. 1817;--WILKINS'S Magna Graecia, fol. 1807;--DESGODETZ'S buildings of Rome, 2 vols. fol. tra. 1771;--TAYLOR and CRESYS' Antiquities of Rome, 2 vols. fol. 1821-2;--DURAND, Recueil des Edifices, oblong fol. 1801;--PUGINS' Specimens of Gothic Architecture, 2 vols. 4to. 1823;--BRITTONS' Architectural Antiquities of Great Britain, 4 vols. 4to. 1815, &c.;--TREDGOLD'S Elements of Carpentry, 4to. 1821;--NICHOLSON'S Architectural Dictionary, 3 vols. 4to. 1821.