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sidered more in relation to a building than a mere cornice, and requires rustic quoins, if possible, at the angles when used. Chambers, speaking of this example, says, that "when it is used to finish a plain building, the whole height is found by dividing the height of the whole front into eleven parts, one of which must be given to the entablature, and the remaining ten to the rest of the front." We suspect that the smallness which is assigned by this author to its height has been induced by some error, and that a better rule would be induced by assigning to the cornice its proper height, according to the laws above hinted at, and proportioning the rest of the entablature from the cornice thus obtained.

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2727. In figs. 949, 950, and 951. are given three examples of block cornices (the second being by Palladio), whose proportions the figures sufficiently show without here giving a detail of their parts. The height of either should not be less than one fifteenth of the height of the building.

Fig. 952.

Fig. 954.

Fig. 953.

2728. Figs. 952. and 953. are block cornices, which we have adopted from Chambers, the first being from a palace at Milan, and the other, by Raffaelle, in a house in the Lungara at Rome. The height of these, says the author, and we agree with him, need not exceed one sixteenth part of the whole front, nor should either be less than one eighteenth. Fig. 954. is what is called an architrave cornice, which was frequently employed by the old masters. It seems well adapted to the entablatures of columns bearing arches, being rather in the nature of an impost; but it is useful, changing it to suit the order in cases where the height does not admit of the whole of the entablature being used over the order.

SECT. XIX.

PROFILES OF DOORS.

2729. One of our objects in this work has been to impress throughout on the minds of our readers that architecture does not depend on arbitrary laws; and though we may not have proved satisfactorily to the student that the precise laws have been exactly stated, we trust we have exhibited sufficient to show and convince him that there was a method and limit in the works of the ancients which in the best times prevented the artists from falling on either side into excess.

2730. In fig. 955. we give a door with its architrave, frieze, and cornice, without relation to mouldings, but merely considered in the masses. Its proportions correspond with those most usually adopted; that is, its height is twice its width, the entablature is one fourth of the height of the opening, and the architraves on each side, together, two sixths of the width. The opening, therefore, measuring it in terms of the width of the architrave, will be 6 parts wide and 12 high, and its area consequently 72 parts. Now

it will be found that the solid parts of this are exactly on their face two thirds of this area; for up to the top of the opening each architrave being equal to 12, the sum will be 24; and the entablature being 8 wide and 3 (one fourth of twelve) high, 8 x 3=24; which added to 24 for the architraves gives 48 for the solids, and 13, as above stated. The same analogy does not seem to hold in respect of doors and windows, of making the voids equal to the supports and weights, as in intercolumniations; nor indeed ought we to expect to find it, for the conditions are totally different, inasmuch as no door can exist except in a wall, whereas the office of columns is connected with the weight above only. We trust, therefore, we have shown enough to keep the reader's mind alive to some such law as above developed, without insisting very strongly on a minute attention to it in detail.

2731. We shall now, before submitting any examples of doorways

Fig. 955.

to the reader, touch upon some important points that must be attended to; the first of which is, that all gates and doors, independent of all other considerations, must be of sufficient size for convenient passage through them. Hence internal doors must never be reduced under 2 feet 9 or 10 inches, and their height must not be under 6 feet 10 inches or 7 feet, so as to admit the tallest person to pass with his hat. There are minimum dimensions for ordinary houses in the principal floors; but for houses of a superior class, which are provided with what may be called state apartments, widths of 4, 5, and 6 feet, folding doors and the like, will not be too great for the openings, and the heights will of course be in proportion. The entrance doors of private houses ought not to be under 3 feet 6 inches, nor ordinarily more than 6 feet in width; but in public buildings, where crowds of people assemble, the minimum width should be 6 feet, and thence upwards to 10 or 12 feet. No gate should be less than 9 feet wide; and when loaded waggons or carts are to pass through it, 11 or 12 feet will not be too much. As a general observation we may mention that all doors should open inwards, for otherwise the person entering pulls the door in his face, which is an inconvenient mode of entering a room. Also when the width of a door is greater than 3 feet 8 inches it should be formed in two flaps, by which three advantages accrue: first, that the door will not occupy so much space for opening; second, that each door will be lighter; and, third, that the flaps will more nearly fold into the thickness of the wall. Chambers properly says, "That in settling the dimensions of apertures of doors regard must be had to the architecture with which the door is surrounded. If it be placed in the intercolumniation of an order, the height of the aperture should never exceed three quarters of the space between the pavement and the architrave of the order; otherwise there cannot be room for the ornaments of the door. Nor should it ever be much less than two thirds of that space, for then there will be room sufficient to introduce both an entablature and a pediment without crowding; whereas if it be less it will appear trifling, and the intercolumniation will not be sufficiently filled. The apertures of doors placed in arches are regulated by the imposts, the top of the cornice being generally made to level with the top of the impost; and when doors are placed in the same line with windows, the top of the aperture should level with the tops of the apertures of the windows; or if that be not practicable without making the door much larger than is necessary, the aperture may be lower than those of the windows, and the tops of all the cornices made on the same level."

2732. To say that the principal door of a building should if possible be in the centre of the front would seem almost unnecessary; but it is not so, perhaps, to inculcate the necessity of its being so situated in connection with the internal arrangement of the building as to lead with facility to every part of it, being, as Scamozzi observes (Parte Secunda, lib. vi. c. 4.), like the mouth of an animal placed in the middle of the face, and of easy communication with the inside. In the internal distribution the doors should as much as possible be opposite one another on many accounts, not the least whereof is the facility thus given to ventilation; but such a disposition also gives the opportunity of a far better display of a series of rooms, which on occasions of fêtes imparts great magnificence to the apartments. In this climate it is well to avoid too great a number of doors, and they should never, if it can be avoided, be placed near chimneys, because of subjecting to draughts of air those who sit near the fire. Generally the doors in a room should be reduced to the smallest number that will suit the distribution, and the practice of making feigned or blank doors, though sometimes necessary, should if possible be excluded.

2733. The ornaments with which doors are decorated must of course depend on the building in which they are used; and as this is a matter in which common sense must direct the architect, it is hardly necessary to say that the ornaments applied to them in a theatre would ill suit a church.

2734. The composition and designing of gates and their piers must of necessity suit the occasion, as well as the folding gates attached to them, for the enclosure of the parks,

gardens, and other places they are to serve. There are few finer examples in the higher class of this species of design than the celebrated gates at Hampton Court.

2735. The evil days on which we have fallen in this country, in respect of the arts, precludes the hope of again seeing the doors of our buildings ornamented with bassi relievi and bronze ornaments, a practice common among the ancients no less than among the revivers of the arts; witness the doors of St. Peter's, and, above all, those monuments of the art, the doors of the baptistery at Florence by Lorenzo Ghiberti, wherein art rises by being made only subservient to the holy purpose to which it is the mere handmaid. In the mention of doors those of San Giovanni Laterano at Rome must not be omitted; they have the credit of having been the enclosures to the temple of Saturn in the ancient city.

2736. The manufacture of doors has been already sufficiently noticed in the Second Book; and it therefore only remains for us to subjoin a few examples, which, we think, among many others, deserve the attention of the student.

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2737. Fig. 956. is an external doorway designed and executed by Vignola, at Caprarola, not a great distance north of Rome; it must speak for itself: if the reader be of our mind, he will see in it a beautiful handling of the subject; but we cannot further answer for our opinion, knowing as we do that some of the reviewers of these days may find out that it possesses no aesthetic beauties. There are cases where imitation has been permitted; and the sanction for our opinion is, that it has been imitated by one whom we and all others hold in reverence at Greenwich Hospital, though, as we think with Chambers, for the worse. "The aperture is in the form of an arch, and occupies somewhat more than two thirds of the whole height. It is adorned with two rusticated Doric pilasters and a regular entablature. The height of the pilasters is 16 modules, that of the entablature 4. The width of the aperture is 7 modules, its height 14, and the breath of each pier is 3 modules." To the detail of Chambers we have to add that the void in this example, which has no analogy to that which as a general rule we gave in the commencement of the section, is about one third of the area of the whole design, the void being to such area as 7 57 to 20.88.

2738. Fig. 957. is a design by the last-mentioned master, in which the void is as nearly as possible equal to one third of the area, the supports another, and the weights the other third in other terms, the aperture occupies two thirds of the whole height and one half of the whole breadth, being, in fact, a double square. Its entablature has an alliance with the Tuscan order, and the cornice is equal to one fifteenth of the whole height of the door. These two examples are especially external; those which follow are from their rature applicable in general form to either external or internal doorways.

2739 Fig. 958. is a doorway in the Cancellaria at Rome, and is from the design of Vignola. The width is one half

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the whole entablature a quarter of its height, and the architrave one sixth of the width of the aperture. The face of the pilasters or columns at the sides must be regulated by the lower fascia of the architrave, and their breadth is to be a semidiameter.

2741. Fig. 960. is by Vignola, and is in the Farnese palace at Rome. The opening is twice the width in height, and the entablature is three elevenths of the height of the aperture, one of the foregoing elevenths being given to the architrave. The whole of the ornament on the sides is, including architraves and pilasters, equal to two sevenths of the width of the aperture. The cornice is Composite, with modillions and dentils, and the frieze is enriched with a laurel band.

2742. Fig. 961., another of the examples given by Chambers, is believed to be by Cigoli. The void is rather more in height than twice its width. The impost of the arch is equal to half a diameter, the columns are rather more than nine diameters high, and rusticated with five square cinctures. The entablature is not so much as one quarter of the height of the column, and its tablet is equal to the width of the aperture.

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Fig. 963.

2743. Fig. 962. is by Inigo Jones, and the aperture may be twice as high as it is wide. The architrave may be a sixth or seventh of the width of the aperture, the top of it being level with the astragal of the columns, which are Corinthian, and ten diameters in height. They must be so far removed on each side from the architrave as to allow the full projection of their bases. The entablature may be from two ninths to one fifth of the column, and the pediment should be regulated by the rules given in Sect. XVII. (2722.).

2744. Fig. 963. is by Serlio. The aperture may be a double square, or a trifle less; the diameter of the columns a quarter of the width of the aperture, or a trifle less; their height 8 to 8 diameters; the entablature about a quarter of the height of the columns, and the pediment should be drawn in conformity with the directions in Sect. XVII.

SECT. XX.

WINDOWS.

2745. Windows, of all the parts of a building, are those which require the greatest nicety in adjustment between the interior and exterior relations of them. The architect who merely looks to the effect they will produce in his façades has done less than half his work, and deserves no better name or rank than that of a mere builder. It seems almost useless to observe that the windows of a building should preserve the same character, that those in each story must be of the same height, and that the openings must be directly over one another. Blank windows are, if possible, to be avoided: they always indicate that the architect wanted skill to unite the internal wants of the building with its external decoration. Windows, moreover, should be as far removed as the interior will permit from the quoins of a building, because they not only apparently, but really, weaken the angles when placed too near them.

2746. Vitruvius, Palladio, Scamozzi, and Philibert de l'Orme, besides many other masters, have given different proportions to them as connected with the apartments to be lighted. That these should be different is indicated by the different places in which those masters have written. Nothing, indeed, seems so much to disallow general laws as the proportion of windows to an apartment; according to the climate, the temperature, the

length of the days, the general clearness of the sky, the wants and customs of commerce and of life generally. In hot climates the windows are always few in number and small in dimension. As we approach those regions where the sun has less power and the winter is longer, we observe always an increase in their size and number, so as to enable the inhabitants to take as much advantage as possible of the sun's light and rays. It seems, therefore, almost impossible to give general rules on this subject. We shall on this account endeavour, in the rules that this section contains, to confine ourselves to the sizes which seem suitable in this climate, as respects the proportion of light necessary for the comfort of an apartment.

2747. It is a matter of experience that the greatest quantity of light is obtained for an apartment when lighted by an horizontal aperture in the ceiling. Of this a very extraordinary verification is to be found in the Pantheon at Rome. This edifice, whose clear internal diameter is 142 feet 6 inches, not including the recesses behind the columns, is nearly 74 feet high to the springing of the dome, which is semicircular. The total clear number of cubic feet in it may therefore be taken in round numbers at 1,934,460 cubie feet. Those who have visited it well know that it is most sufficiently and pleasingly lighted, and this is effected by an aperture (the eye, as it is technically called,) in the crown of the dome, which aperture is only 27 feet in diameter. Now the area of a circle 27 feet in diameter being rather more than 572 feet, it follows that each superficial foot of the area lights the astonishing quantity of nearly 3380 cubic feet. Independent of all considerations of climate, this shows the amazing superiority of a light falling vertically, where it can be introduced. But in a majority of cases the apertures for light are introduced in vertical walls; and the consequence is, that a far greater area of them for the admission of light becomes necessary. In considering the question it must be premised that a large open space is supposed before the windows, and not the obstructed light which it is the lot of the inhabitants of closely-built streets to enjoy. Again, it is to be recollected that in the proportioning of windows it is the apartments on the principal floor that are to be considered, because their width in all the stories must be guided by them, the only sariety admissible being in the height. In this country, where the gloom and even darkness of wet, cloudy, and foggy seasons so much prevails, it is better to err on the side of too much rather than too little light, and when it is superabundant to exclude it by means of shutters and blinds. We are not very friendly to the splaying of windows, because of the irregularity of the lines which follows the practice; but, it must be admitted, it often becomes necessary when the walls are thick, and in such cases a considerable splay on the inside increases the light in effect by a great diminution of shade. It is well, if possible, to have an odd number of windows in an apartment: nothing wherein contributes more to gloom than a pier in the centre.

2748. We do not think it necessary to advert to the rule of Palladio for the dimensions of windows given in the first book of his work, chap. 25.; because, were it true for the climate of northern Italy, it would not be so for that of Great Britain; neither are we at all satisfied with that which in his practice Sir William Chambers says he adopted, and which is as follows, in his own words:" I have generally added the depth and height" we suppose width "of the rooms on the principal floor together, and taken one eighth part thereof for the width of the window; a rule to which there are few objections: admitting somewhat more light than Palladio's, it is, I apprehend, fitter for our climate than his rule would be." This rule is empirical, as indeed is that on which we place most dependence, and to which we shall presently introduce the reader, being ourselves inclined to the belief that in the lighting a room there is a direct relation between the area of the aperture admitting the light and the quantity of cube space in the room. Indeed the law which we are about to give is one founded on the cubic contents of the apartment; and if the results bore a regular ratio to that quantity, the discussion would be at an end, for we should then have only to ascertain the cubic contents, and, knowing how much an area of light one foot square would illuminate, the division of one by the other would supply the superficies of windows to be provided. Our own notion on this subject is, that I foot superficial of light in a vertical wall, supposing the building free from obstruction by high objects in the neighbourhood, will in a square room be sufficient for 100 cube feet if placed centrally in such room. It will, however, immediately occur to the reader, that this rule cannot in many cases satisfy the requirements of an apartment as respects the quantity of light necessary for its proper illumination. The subject is beset with numerous difficulties, which to overcome requires the greatest skill. In the case of an apartment, long as compared with its width, it is well known to every practical architect that windows of the same collective area at either of the narrow ends of such apartment will light it much more effectively than if the same area of light were admitted on either of the long sides, and most especially so, if it should happen that on such long side there were a pier instead of a window in the centre of such side. In illustration of what we mean, let us refer the reader to the ball room at Windsor Castle, an apartment 90 feet long, 34 feet wide, and 33 feet high. This room is lighted from the northern narrower side by a window nearly occupying the

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