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ARCHITECTURE, in the general sense of the word, is the art of erecting durable, commodious, healthful and handsome buildings of all kinds, adapted to the purposes of the builder. According to the objects to which it is applied, architecture is commonly divided into civil architecture, military architecture (see Fortification), and naval architecture. For the sake of convenience, further divisions are sometimes introduced, such as hydraulic, mining, &c, architecture. Upon the continent of Europe, architecture is often divided into private and public. The latter includes all structures commonly undertaken or particularly superintended by government. In Germany and France, there is a building police, which oversees both public and private edifices, and takes care that securitv and health are provided for in both.1?here is something divine in man, which prompts him to look beyond the mere supply of his necessities, and to aim continually at higher objects. He therefore soon expected from his habitation and his temples more than mere utility. He aimed at elegance, and architecture became, by degrees, a fine art, differing essentially, however, from the other line arts in these respects ; 1, that it is based on utility; 2, that it elevates mathematical laws to rules of beauty. Painting and sculpture are only the expression of the feeling of the beautiful. On the contrary, every creation of architecture must appear to have utility in view. A column or an architrave, which supports nothing, appears ridiculous, and every part of a building ought to show the purpose for which it is designed. Architecture 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 caver® and mound ;* the Chinese architecture is modelled from the tent; the Grecian is derived from the wooden cabin, and the Gothic from the bower of trees.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.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* Wilkins' Vitruvius, p. xvii. for a great length of time, and makes the foundation equally secure with one of brick or stone.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 paraboloid, 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, whiclj 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.*The swell of the shafts of columns was called the entasis by the ancients. It has been lately found,f that the columns of the Parthenon, at Athens, which have been commonly supposed straight, deviate about an inch from a straight line, and that 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. 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 an* See Tredgold's Principles of Carpentry, p. 50. t By Messrs. Allason and Cockerel!. See Brande's Journal; vol. x. p. 204. ©tent 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 lighthouses at Eddystone and Bell Rock. But many of our modern stone walls, for the sake of cheapness, have only one face of the stones 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. 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. 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 pise, 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.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. The floor is the lateral continuation or connexion of beams by means of a covering of boards.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 hntel, 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 keystone, but is not more essential than any other. In regard to the shape of the arch, its most simple form is that of the semicircle. 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 ki 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. 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 30 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 sideways, 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. 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. 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, 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 is one in which the two ends spring from unequal heights. The horseshoe or Moorish arch 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 is concavoconvex, 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 abut ments, or supporting walls. The span i? the distance from one springing line to the other. The wedgeshaped stones, which form an arch, are sometimes called voussoirs, the uppermost being the keystone. 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. 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 side way pressure of an arch is veiy 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 tiebeam of a roof. This is the case in the cathedral of Milan and some other Gothic buildings.*In an arcade, or continuation of arches, it is only necessary that the outer supports of the termi nal arches should be strong enough to re sist horizontal pressure. In the interme diate 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.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.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* Cadell's Journey through Carniola and Italy, vol. ii. p. 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 necessaiy 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 keystone, 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 2000 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. 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 iome, which is very great. The walls of he Roman Pantheon are of great depth md solidity. In order that a dome in itlelf should be perfectly secure, its lower parts must not be too nearly vertical, "ince,m 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, hi Paris, had, originally, a wooden dome more than 200 feet in diameter, and only one foot in thickness. This has since been replaced by a dome of iron.The roof is the mostcomVOL. i. 29 ings, 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 platformroof 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. 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, and where there are two portions to the roof, of different obliquity, it is a curb, or mansard roof. 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.* To counteract this lateral force, a tiebeam, as it is called, extends across, receiving the ends of the rafters, and protecting the wall from their horizontal thrust. To prevent the tiebeam from sagging, or bending downward with its own weight, a kingpost 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. Queenposts are sometimes added, parallel to the kingpost, in large roofs ; also various other connecting timbers. In Gothic buildings, where the vaults do not admit of the use of a tiebeam, the rafters are prevented from spreading, as in an arch, by the strength of the buttresses. In comparing the lateral pressure of a high roof with that of a low one, the length of the tiebeam 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* The largest roof that has hitherto been built is supposed to have been that of the ridinghouse at Moscow. Its span was 235 feet, and the slope of the roof about 19 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 tiebeams were supported by several vertical pieces, notched to this arch, and the whole stiffened by diagonal braces. Tredgotd/s Carpen try, p. 87. 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 the U. States, after being boarded, receive a secondaiy 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 head of the Grecian and Roman styles, but their component parts ought previously to be understood.The front or fapade 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 8 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 ;* 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.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. 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 is a convex moulding, the section of which is a semicircle or nearly so. The astragal is like the torus, but smaller. The ovolo is convex, but its outline is only the quarter of a circle. The echinus resembles the ovolo, but its outline is spiral, not circular. The scotia is a deep, concave moulding. The cavetto is also concave, and occupying but a quarter of a circle. The cymatium is an undulated moulding, of which the upper part is concave, and the lower convex. The ogee or talon is an inverted cymatium. The fillet is a small, square or flat moulding.fIn architectural measurement, a diameter means the* 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.t By a singular mixture of derivations, the Greek, Latin, Italian, French and English languages are laid under contribution for the technical terms of architecture. width of a column at the base. A module is half a diameter. A minute is a 60th part of a diameter.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. 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. 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 fallen, 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.We come now to the different styles of architecture.I. 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, if ever, employed by them. 3. Their columns were o numerous, close, short, and very large, being sometimes 10 or 12 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 palmleaves, 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 70 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 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. II. 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 then* 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 shop windows iii summer time. The verandah, sometimes copied in dwelling houses, 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.III. The Grecian style, Grecian architecture, from which have been derived the most splendid structures of later ages, had 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.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 6 or 7 . centuries. They were lost sight of in the dark ages, and again revived by the Italians, at the time of the restoration of letters. The Greeks had 3 orders, called the Doric? < Ionic and Corinthian. These were adopted a^nd modified by the Romans, who also added 2 others, called the Tuscan and Composite.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 6 diameters in height. In the older ¦ examples, as those at Psestum, it is but 4 or 5. The shaft; had no base, but stood directly on the stylobate. It had 20 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 3 parts by vertical furrows, and ornamented beneath by guttce, or drops. The spaces between the triglyphs were called metopes, and commonly contained sculptures. The sculptures representing Centaurs and Lapithse, 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 guttce. The best specimens of the Doric order are found in the Parthenon, the Propylsea and the temple of Theseus, at Athens.The Ionic is a lighter order than the Doric, its column being 8 or 9 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. Others were used in different parts of Greece. The shaft had 24, 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 2 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 Amnion. 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 denlels, 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, 70 years since, but is now extinct.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 10 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,* above which were 8 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. The Corinthian order was much employed in the subsequent structures of Rome and its colonies.Caryatides. The Greeks sometimes departed so far from the strict use of the orders, as to introduce statues, in the place of col umns, to support the entablature. Statues * The origin of the Corinthian capital has been ascribed to the sculptor Callimachus, 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.of slaves, heroes and gods appear to have oeen 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. 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 7 different species of temples. These were, 1. The temple with antes,. In this, the front was composed of pilasters, called antm, on the sides, and 2 columns in the middle. 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 6 in front and in rear, and 11, counting the angular columns, on each side. 5. The dipteral, with a double row of columns all round the cell, the front consisting of 8. 6. The pseudodipteral 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 hypcethral temple had the centre of its roof open to the sky. It was colonnaded without, like the dipteral, but had 10 columns in front. It had also an internal colonnade, called peristyle, on both sides of the open space, and composed of 2 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.*The theatre of the Greeks, which* The intercolumniation, or distance between the columns, according to Vitruvius, was differently arranged under the following names:In the pycrw29* was afterwards copied by the Romans was built in the form of a horseshoe, 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 mova ¦ ble 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.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 things, 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.IV. 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 2 new ordersthe Tuscan and the Composite.The order derived from the. ancient Etruscans is not unlike the Doric deprived of its triglyphs and mutules. It had a simple base, containing 1 torus. Its column was 7 diameters in height, wTith an astragal below the capital. Its entab^ lature, 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.The Romans modified the Doric order by increasing the height of its column to 8 di style, the columns were a diameter and a half apart; in the systyle, they were 2 diameters apart; in the diastyle, 3 j in the arceostyle, more than 3 3 in the eustyle, 2|. KJt/V IlilVlll JL J^IV JL KJ ll/JJ. ameters. 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.The Romans diminished the size of the volutes in the Ionic order. They also introduced a kind of Ionic capital, in which there were 4 pairs of diagonal volutes, instead of 2 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 modem Ionic.The Composite order was made by the Romans out of the Corinthian, simply by combining its capital with that of the diagonal, or modern Ionic. 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. 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 completely 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 Coliseum 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 2 stories, or with 2 tiers of columns, one over the other. The earliest Christian churches at Rome were sometimes called basilicce, 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 thermal, or baths, were vast structures, m which multitudes of people could bathe at once. They were supplied with warm and cola water, and fitted up with numerous rooms for purposes of exercise and recreation. 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 Adrian, Roman architecture is considered to have been on the decline. Among the marks of a deteriorated style, introduced in the latei periods, wTere 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.V. 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 GrecoGothic 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. The Saxon architecture, used anciently in England, has some things in common with this style.VI. Saracenic, or Moorish 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 inse domes of the Oriental mosques, which are sometimes large segments of a sphere, appearing as if inflated, and, at other times, concavoconvex in their outline, as in the mosque of Achmet. The minaret is a tall, slender tower, peculiar to Turkish architecture. A peculiar flowery decoration, called arabesque, is common in the Moorish buildings of Europe and Africa. Some distinguish the Arabian style, formed after the Greek, and the Moorish, formed after the remains of the Roman buildings in Spain, which seems a good division. With regard to the latter, nobody can behold the remains of the Moorish buildings at Grenada, Seville and Cordova, without admiration. The Arabian style is particularly distinguished by light decorations and splendor.VII. Gothic style. By this style is generally understood what is strictly called the modern Gothic, which flourished after the destruction of the Gothic kingdom by the Arabians and Moors. The old Gothic style, which probably originated under Theodoric, king of the Ostrogoths, during whose reign in Italy the Romans, with little sense of beauty, imitated the ancient Roman style, is coarse and heavy. The style now called Gothic exhibits a wonderful grandeur and splendor, and, at the same time, the most accurate execution; yet it is only in modern times that its great masterpieces, as the minster of Strasburg, the cathedral of Cologne, &c, have begun to be justly appreciated. Very great attention is, at present, paid to the study of this style. Its principle seems to have originated in the imitation of groves and bowers, under which the Druids performed their sacred rites. Its striking characteristics are, its pointed arches, its pinnacles and spires, its large buttresses, clustered pillars, vaulted roofs, profusion of ornaments, the general predominance of the perpendicular over the horizontal, and, in the whole, its lofty, bold spirit. 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 Any high building erected above the roof is calledif long and acute, a spire; and, if short and light, a lantern. Towers of great height in proportion to their diameter are called turrets. The walls of Gothic churches are supported, on the outside, by lateral projections, extending from top to bottom, at the corners, and between the windows. These are called buttresses, and they are rendered necessary to prevent the walls from spreading under the enormous weight of the roofs. 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 any thing like an entablature. Their use is to aid in sustaining the vaults under the roofj which rest upon them at springing points 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 pendentives. 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, admits of richer ornaments, and is 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 often dif ficult to accomplish what was achieved by the builders of the middle ages.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 any thing like thorough and genuine Gothic is attempted,a thing, however, rarely undertaken, as yet, in the U. States. 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 cities and villages. (For further information, see, among other works, Bigelow's Technology, Boston, 1829, p. 112-152, from which the above article is extracted, with the exception of the first paragraph.)