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port their own entablatures, which must be the consequence in insulated columns.

When the front of a building is to have two or more orders in the altitude, the succession ought to be complete, otherwise the harmony will be destroyed by the violent contrast of the parts. When columns are attached, a recedure of the superior order will not offend the eye in any great degree, nor will the solidity of the structure be impaired this is to be seen in the theatre of Marcellus; but when the stories of orders are insulated, it is necessary that the axis of the superior and inferior columns should be in the same vertical lines. If the upper or der only insists in the middle of that below in two equidistant parts from the middle, the portions of the entablature of the lower order in which there is no superior order are generally finished with a balustrade,

level with the sills of the windows.

In England we have few examples of more than two ranges of columns in the same front; for when there are three, it is difficult to preserve the character of each order in the intercolumnial decorations, without some striking defects. The first and second orders should stand upon a plinth, and the third also when there is one; the point of view regulating the two upper plinths. In this case pedestals should be omitted in the upper orders, and if there is one, or a balustrade under the windows, the base and cornice should have but a small projection, and should be continued to profile upon the sides of the columns. In raising stories of arcades upon each other, with orders decorating the piers, the inferior columns should be placed upon a plinth, and the superior ones upon a pedestal, in order that the arches may obtain a just proportion.

Pediments. A pediment is a part of a building having a horizontal cornice below, and two equally inclined ones, or an arched cornice above, joined at the extremities of the horizontal one; the cornices including a plane surface within, called the tympanum, which is therefore either a triangle or the segment of a circle.

This definition does not comprehend every species of pediments which have been absurdly introduced; but it may be said to be the only genuine one, as pediments 'represent the ends of roofs, and were originally intended to discharge the rain from the middle of the building, by compelling it to descend and fall over the flanks or extremes, and not over the front, which must be the case with every other figure that

can be introduced except those of a polygonal form, which present their interior angles to the horizontal cornice, or the exterior ones upwards. To find the pitch of the pediment Vitruvius directs as follows: divide between the extremities of the cymatium of the corona into nine equal parts, and one makes the height of the tympanum ; but this rule is not correct, as the tympanum will vary its angles according as there are more or less mouldings of the inclined cornices within the extremities of the cymatium of the corona; for since the middle part by this rule is invariable, and the broader the parts are of the inclined cornices within each extremity of the cymatium of the corona, or rather within the under edge of the fillet of the sima upon each inclined cornice, the less is the base of the tympanum, and consequently the vertical angle less obtuse, and the base angles less acute; but if this height extended to the meeting of the two under sides of the fillets of the sima, or crowning moulding, then the figure of the tympanum would be invariable. The Vitruvian rule has been thought by many to be too low; but it is to be recollected, that that of the Parthenon at Athens, which has an octostyle portico, is nearly of this proportion; that of the temple of Theseus, which has an hexastyle portico, is about one-eighth; that of the Ionic temple on the Ilyssus, and of the Doric portico, which are both tetrastyle, are about one-seventh; the tympanum of the pediment of the door on the Tower of the Winds is about one-fifth of the span. The edifices here mentioned are all Athenian buildings. From this comparison it would appear, that a kind of reciprocal ratio subsists between the extension of the base of the tympanum, and its height. Indeed, if a fixed ratio were applied to windows, the pediment would frequently consist of a cornice without the tympanum. It is therefore with great reason that we often make the pitch of pediments of windows more than those which crown porticos, or the fronts of buildings. The plinths by which pediments are sometimes decorated are called acroterions, or acroters: the two which present triangular faces at the extremes, have their heights, according to Vitruvius, half of that of the tympanum, and the middle one saddled on the summit is one-eighth part higher than those at the extremes. Pediments owe their origin most probably to the inclined roofs of primitive huts. Among the Romans they were only

used as coverings to their sacred buildings, till Cæsar obtained leave to cover his house with a pointed roof, after the manner of temples. In Grecian antiquity we meet only with triangular pediments, and in Roman buildings we meet with both the triangular and circular. In rows of openings, or niches, both kinds of pediments were employed in the same range, and disposed in alternate succession. The horizontal cornices of pediments should never be discontinued, as may be seen in many of the street houses of London, in order to give room for a fan light, and to lessen the expenses of the frontispiece, by introducing shorter columns and a less massy entablature: for since the horizontal cornice represents the tie-beam, and the inclined ones the rafters, the columns will appear to have a tottering effect by spreading them out at the top beyond the extremities of their bases.

Vitruvius observes, that the Greeks never used mutules, modillions, or dentils, in the front, in which the end of the roof, or fastigium, appears, because that the ends of the rafters and the ends of the laths which support the tiles only appear at the eaves of the building. Now, as mutules and dentils originated from the projecting ends of the rafters and laths, following the course of nature, it would have been absurd to introduce them into the pediment.

However just this reasoning appears, we find from the remains of Grecian antiquity this assertion only verified in the inclined cornices of the pediment: for mutules are constantly employed in the horizontal cornice; but neither mutules, modillions, nor dentils, on the sloping sides: at least, when any of the edifices in Greece appear with those innovations, they were introduced during the time it was a province of the Roman empire. Of this practice at Rome the Pantheon and the frontispiece of Nero are examples of modillions; and the temple of Fortune one where dentils are used. In the inclined cornices of pediments the sides of the modillions and dentils are planes perpendicular to the horizon and to the front of the edifice; and in the same vertical planes with those of the modillions or dentils of the horizontal cornice.

Balustrades. A balustrade is a range of small columns, called balusters, supporting a cornice, used as a parapet or as a screen to conceal the whole or a part of the roof: it is also sometimes used as a decoration for terminating the building. Balustrades are

employed in parapets, on the margins of stairs, or before windows, or to inclose terraces or other elevated places of resort, or on the sides of the passage way of bridges. It is remarkable, that there are no remains of balusters to be seen in any ancient building. In the theatres and amphitheatres of the Romans the pedestals of the upper orders were always continued through the arcades, to serve as a parapet for the spectators to lean over. The lowermost seats next to the arena in the amphitheatres, and those next to the orchestra in the theatres, were guarded by a parapet or podium. The walls of ancient buildings generally terminated with the cornice itself, or with a blocking course, or with an Attic. In the monument of Lysicrates at Athens, which is a small beautiful building, the top is finished with fynials, composed of honeysuckles, solid behind, and open between each pair of fynials: each plant or fynial is bordered with a curved head, and the bottom of each interval with an inverted curve. Perhaps terminations of this nature might have been employed in many other Grecian buildings, as some coins seem to indicate; but this is the only existing example of the kind. The temples in Greece are mostly finished with the cornice itself. This was also the case with many of the Roman temples; but as there are no remains of balustrades in ancient buildings, their antiquity may be doubted: they are, however, represented in the works of the earliest Italian writers, who perhaps may have seen them in the ruins of Roman edifices. When a balustrade finishes a building, and crowns an order, its height should be proportioned to the architecture it accompanies, making it never more than four-fifths, nor less than twothirds of the height of the order, without reckoning the zocholo, or plinth, on which it is raised, as the balustrade itself should be completely seen at a proper point of view. Balustrades that are designed for use should always be of the height of parapet walls, as they answer the same purpose, being nothing else than an ornamental parapet. This height should not exceed three feet and a half, nor be less than three feet. In the balusters, the plinth of the base, the most prominent part of the swell, and the abacus of their capital, are generally in the same straight line: their distance should not exceed half the breadth of the abacus or plinths, nor be less than one-third of this measure. On stairs or inclined planes the same proportions are to be observed as on

horizontal ones. It was formerly customary to make the mouldings of the balusters follow the inclination of the plane; but this is difficult to execute, and, when done, not very pleasant to the eye: though in ornamental iron-work, where it is contined to a general surface, passing perpendicularly by the ends of the steps, it has a very handsome appearance. The breadth of pedestals, when placed over an order, is regulated by the top of the shafts, the die being always equal thereto. When balustrades are placed upon the entablature of an order, over the intercolumns or interpilasters, and the base and cornice of the balustrade continued, so as to break out and form pedestals over the columns or pilasters; the breadth of the die of the pedestals should be equal to the breadth of the top of the shafts; and where there is no order, the breadth of the die is uever more than its height, and very seldom narrower; and the dies of the pedestals are frequently flanked with half dies, particularly when the range of balusters is long. This is not only apparently necessary, but is in reality useful in shortening the range, and forming a better support for the ends of the rail.

Attics. An Attic is a part of a building standing on the cornice, similar in form to that of a pedestal; and is either broken or continued. The use of an attic is to conceal the roof, and to give greater dignity to the design. The Romans employed attics in their edifices, as may be seen in the remains of the triumphal arches, and piazza of Nerva. In the arch of Constantine pedestals are raised over the columns as high as the base of the attic, and these pedes tals are again surmounted with insulated statues. In the ruins of Athens there are no attics to be found: there is one, how ever, over a Corinthian colonade at Thessalonia, with breaks forming dwarf pilasters over the columns; and with statues placed on front of the pilasters, as in the arch of Constantine. The attic carried round the two courts of the great temple of Balbec is also broken into dwarf pilasters over the columns and pilasters of the order; and the dwarf pilasters have blocking courses over them, on which statues are supposed to have been placed. Attics are very disproportional in the ruins of these ancient edifices; some of them being nearly one-half of the height of the order. The moderns make their height equal to that of the entablature; as to the proportion of the height of the members it may be the same as that fer pedestals.

Doors. Doors are apertures in exterior walls, used for passage into public and private buildings; and in the interior for communication from one apartment to another. In the fourth book of Vitruvius rules are laid down for Doric, Ionic, and Attic doors, all of which have apertures narrower at the top than at the bottom. These trapazoidal closures of apertures have the property of shutting themselves, which, perhaps, might have occasioned the introduction of this form, and are useful in modern times for raising the door above the floor in the act of opening, in order to keep it clear of the carpet. Examples of them are to be found among the ruins of ancient edifices; they have also been introduced by a few modern architects. The apertures of doors of small dimensions are most commonly closed with lintels. Doors, in general, are regulated in their apertures by the size of a man, so ás never to be smaller than that he might pass freely through them; they are 'seldom less than two feet nine inches in width, by six feet six inches in height, except in confined situations, and where utility is beyond any other consideration.

Doors of entrance vary in their dimensions according to the height of the story, or magnitude of the building in which they are placed. In small private houses four feet may be the greatest width, and in most cases three feet six inches will be sufficient. The lintels of doors should range with those of the windows; and the width of their aperture should not be less than that of the windows. A good proportion of doors is that where its dimensions has the ratio of three to seven; their height should never be less than twice, nor more than twice and a half their breadth. In the entrance doors of public edifices, where there is a frequent ingress and egress of people, and often crowded, their width may be from six to ten feet. Inside doors, or doors of communication, should be in some measure proportioned to the height of the stories; however, there is a certain limit for the dimensions of their apertures, which they should not exceed; for the difficulty of shutting the door will be increased by its magnitude; therefore the apertures of doors which are intended to shut in one breadth should never exceed three feet six inches. In palaces and in noblemen's houses, where much company resort, and in state apartments, all the doors are frequently thrown open: they are made much larger than other doors, being from four to six feet in width, with folding leaves. The proportion of the apertures of such

doors will often be of a less height than that of twice the breadth, as all the rooms in the same story have a communication with one another, the whole of the doors in that story will have one common height.

The apertures of exterior doors placed in blank arcades are regulated by the imposts, the top of the aperture being generally made level with the springing of the arch; or if the door has dressings which include a cornice, the top of the cornice ought to be on the same level with the springing of the arch. With regard to the situation of the principal entrance, it is evident that the door should be in the middle, as it is not only more symmetrical, but will communicate more easily with all the parts of the building. In principal rooms doors of communication should at least be two feet distant from the walls if possible, that furniture may be placed close to the door-side of the room. The most common method of adorning doors is with an architrave surrounding the sides of the aperture, or with the architrave surmounted with a cornice forming an architrave cornice, or with the architrave frize and cornice forming a complete entablature. Sometimes the ends of the cornice are supported with consoles, placed one on each side of the architrave; and each console is most commonly attached to the head of a pilaster; sometimes the surrounding architrave is flanked with pilasters of the orders, or of some other analogical form. In this case, the projections of their bases and capitals are always within that of the architrave the architrave over the capitals of the pilasters is the same as that of the head of the door, and the parts exactly of the same height, and projections profiling upon the sides of the surrounding architrave. Sometimes, either with or without these dressings, the door is also adorned with one of the five orders, or with columns supporting a regular entablature, frequently surmounted with a pediment. Doors are also sometimes adorned with rustics, which may either be smooth, hatched, frosted, or vermiculated; but their outline must be sharp. The rustics are disposed in contiguity with each other, or are repeated by equal intervals: as to the shafts of columns the rustic cinctures may either be cylindrical or with rectangular faces. In doors with rectangular apertures and rusticated heads, the rus tics are drawn from the vertex of an equilateral triangle within the aperture. The entrance doors of grand houses are often adorned with porticos, frequently in the

manner of Grecian temples; sometimes the plan of the portico may be circular, which should never have less than three intercolumniations, as the entablature would appear to overhang its base, in such a degree as to offend the eye of a beholder.

Windows. A window is an aperture in a wall for the admission of light. The size of windows depends on the climate, the aspect, the cubature, the proportion, the destination, and the thickness of the walls of the place to be lighted; as also on the number and distribution of windows in that place. It is not very easy, even with these data, to determine, with mathematical exactness, the necessary quantity of light; but in private houses, were beauty and proportion are required, the width of windows depends on the height of the principal story; otherwise the apertures will be disproportionate figures of themselves, and also to the whole facade in which they are placed.

The apertures of windows should not only be of shapely figures, and proportioned to the building, but the piers also should, in some measure, be regulated by the breadth of the apertures; at least, certain proportionable limits of this breadth ought to be assigned to that of the piers, so as not to offend the eye by their being too clumsy or too small, and at the same time permit a less or greater quantity of light, for a greater or less depth of rooms. As to the size of the piers, considerable latitude may be taken; but in general, they should not be of less breadth than the apertures, nor more than twice that breadth. In a small building, with only three rooms and three windows in the length, the piers will necessarily be large.

In buildings with a great number of windows in the length, where there are at least three windows in one or more principal rooms; and where there are no breaks, the breadth of the piers may be from once the breadth of the window, to once and a half that breadth; but if there are columns, pilasters, or breaks, the breadth of the pier may be from once to twice that of the apertures, according as the breadth of the pilasters or columns may require, so as to leave a proper repose of wall upon the sides.

The sills of windows should be from three feet to three feet six inches distant from the level of the floor, forming a parapet for leaning upon: these limits are the natural heights of the breasts of windows; but it

is now common, even in ordinary buildings, to make them from two feet to two feet six inches high only. In noblemen's houses, the sills are frequently upon the same level with the floor, and sometimes rise a step or two higher. These circumstances will alter the proportion of the windows, and make them much higher than the double square. The width of all the windows must be the same in the same façade; but the different heights of the stories will require different heights of windows. Were it required to find the quantity of light for a room of given dimensions, it is evident that this will depend upon the area of the inlet and the cubature of the room; therefore, supposing that an aperture containing 20 square feet is sufficient for a room 12 feet square and 10 feet high, that is, 1400 cubic feet, the quantity of light will easily be ascertained for a room of any other given dimensions. Let a room be supposed 25 feet long, 20 feet broad, and 14 feet high, the cubature will be 7000 feet; then, because the cubature of rooms should be as the area of the inlets, the proportion will stand thus :

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This quotient, divided into three parts, gives nearly 32 feet for each window, which is very sufficient for light; and after deducting 12 feet, the breadth of three windows, 13 feet will remain for the four piers, which is a very good proportion: there is also abundant room left for any kind of furnishing above the windows.

An odd number of windows, either in the same length of front, or in the same length of principal rooms, is always to be preferred to an even number; for, since it is necessary to have the door in the middle of

the front, an even number of windows would occasion a pier to be above the opening of the door, contrary either to regularity or to the laws of solidity; and in rooms nothing is more gloomy than a pier opposite the centre of the floor. Windows placed in blank arcades should have the under sides of their lintels in the same horizontal plane with the springing of the arch; or if the windows have a cornice, the springing of the arch ought to be carried as high as the top of the cornice.

The aperture of the windows may be from two-fifths to three-fourths of the breadth of the arcade. In the principal floor, the windows are generally ornamented; the most simple kind of which is, that with an architrave, surrounding the jambs aud lintels of the aperture, and crowned with a frize and cornice. In cases where the aperture is high, in order to make the dressing of a good composition, the sides of the architrave are frequently flanked with pilasters or consoles, or with both; and sometimes with columns, when there is a set-off or proper base, so as not to have a false bearing. When the principal rooms are in the one pair of stairs, the windows of the ground floor are sometimes left entirely plain, and at other times they are surrounded with an architrave; or the rusticated basement, where there is one, terminates upon their margins without any other finish. The windows in the third story are frequently plain, and sometimes surrounded with an architrave. When the windows in the principal story have pediments, the windows of the story immediately above have frequently their surrounding architraves crowned with a frize and cornice. The sills of all the windows in the same floor should be upon the same level. The sills of the windows in the ground story should be elevated five or six feet at the least above the pavement. In the exterior of every building, the same kind of finish or character should be preserved throughout the same story. Mixtures of windows should be avoided as much as possible; or where there is a necessity for introducing Venetian windows, they ought to stand by themselves, as in breaks.

Gates. A gate is an aperture in a wall, which serves for the passage of horsemen and carriages. They are employed as inlets to cities, fortresses, parks, gardens, palaces, and all places to which there is a frequent resort of carriages. In gates which

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