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breadth of the pier equal to the opening. By dividing the latter into twelve parts we have a measure which seems to have prevailed in the mind of the architect, inasmuch as two of them will measure the parts of the pier supporting the archivolts, four the space for the two columns, two for the intervals between the niche and the columns, and four for the niche. Half the diameter of the arch measures the height of the pedestal; the columns are of the height of ten diameters, and their entablature one quarter of the height of the columns. The impost and archivolt are each equal to half a diameter of the column. 2639. Fig. 911. is an example whose employment is not uncommon in the designs of Palladio, and was considered by our great countryman Inigo Jones to be worthy of his imitation. The arch may be taken at about twice its width, and the pier not less than one mor more than two thirds of the width of the aperture.
2640. The example in fig. 912. is from the hand of Vignola, and was executed for on: of the Borghese family at Mondragone, near Frascati. In it the arch is a little more in height than twice its width, and the breadth of the pier columns supporting the arch include a little less than the width of the arch itself. We are not quite satisfied in having here produced it as an example, though, compared with the following one, we scarcely know whether we should not on some accounts prefer it.
2641. The last example (fig. 913.) is one by that great master, Palladio, from the basilica at Vicenza. From the figure it is impossible to judge of its beauty in execution, neither can any imitation of it, unless under circumstances in every respect similar, produce the sensation with which the building itself acts on the spectator; yet in the figure it appears meagre and nothing worth. We can therefore easily account for the conduct of the critics, as they are called, who, never having seen this master's works, indulge in ignorant speculations of the pictorial effects which his compositions produce. Though not entirely agreeing with Chambers in his concluding observations on arcades and arches, we may safely transfer them to these pages. “The most beautiful proportion,” he observes, “for compositions of this kind is, that the aperture of the arch be in height twice its width; that the breadth of the pier do not exceed that of the arch, nor be much less; that the small order be in height two thirds of the large columns, which height being divided into nine parts, eight of them must be for the height of the column, and the ninth for the height of the architrave cornice, two fifths of which should be for the architrave and three for the cornice. The breadth of the archivolt should be equal to the superior diameter of the small columns, and the keystone at its bottom must never exceed the same breadth.”
2642. Vitruvius, in the fifth chapter of his book “On the Forum and Basilica,” in both which species of buildings it is well known that orders above orders were employed, thus instructs his readers:– “The upper columns are to be made one fourth less than those below" (quarta parte minores quam inferiores sunt constituenda), “and that because the latter, being loaded with a weight, ought to be the stronger; because, also, we should follow the practice of nature, which in straight-growing trees, like the fir, cypress, and pine, makes the thickness at the root greater than it is at top, and preserves a gradual diminution throughout their height. Thus, following the example of nature, it is rightly ordered that bodies which are uppermost should be less than those below, both in respect of height and thickness." It is curious that the law thus given produces an exactly similar result to that laid down by Scamozzi, p. 2. lib. v. cap. ii., whereon we shall have more presently to speak. Galliami, Chambers, and others have considered the above-quoted passage of Vitruvius in connection with another in chap. vii. of the same book, which treats of the portico and other parts of the theatre, wherein the author states, after giving several to this question unimportant details, “The columns on this pedestal” (that of the upper order) “are one fourth less in height” (quartà parte minores altitudine sint) “than the lower columns.” The reader will here observe the word altitudine is introduced, which does not appear in the passage first quoted; and we beg him, moreover, to recollect that the last quotation relates entirely to the scene of the ancient theatre, in which liberties were then taken with strict architectural proportion as much as they are in these later days. Those who think that because Vitruvius interlarded his work with a few fables, he is therefore an author not worth consulting, as ephemeral critics have done in respect of that great master of the art, Palladio, may opine we have wasted time in this discussion; but, adopting the old maxim of Horace, “Non ego paucis offendarmaculis,” we shall leave them to the exposure which, with the instructed architect, their own ignorance will ultimately inflict on them, and to the enjoyment of the felicity attendant on a slight knowledge of the subject a person is in the habit of handling. * . . . , i. 2643. We will now place before the student our own reading and explanation of the passage of Vitruvius relative to the use of orders above orders, and attempt n to show what we conceive to be its real meaning. In fig. 914. the diagram || exhibits an Ionic placed above a Doric column: the entablature (which however does not belong to the consideration) being in both cases one || fourth of the height of the column. “Inasmuch as in our previous rules | (following Vignola) it will be recollected that the module of the Doric order is subdivided into twelve, whilst that of the Ionic is subdivided into eighteen parts, we must, for the purpose of obtaining an uniformity of measures in both orders, reduce those of either to the other to obtain similar dimensions. Instead, therefore, of measuring the upper order by itself, which would not afford the comparison sought, we shall have to reduce its established measures to those of the lower one, or Doric, and this, as well as the measurement of the lower order itself, is taken in modules and decimal parts of its semidiameter. Thus, the lower order being 2 modules at its bottom diameter and 1 666 modules at its upper diameter, the means, without descending to extreme mathematical nicety, may be taken at 1.833, which multiplied by the height, 18 modules = 32.994, the area of a section through the centre of the column. Now if the upper columns are to be the same thickness at the bottom as the lower ones are at the top, that is, 1 666 module of the lower order, their upper diameters will be 1 387 (that is, five sixths of the lower diameter), and the mean will be 1:526, which, multiplied by 16, the height, = 24.416 the area of a section down the centre of the column, and just one fourth less than that of the lower column. The investigation tends to show us that we should not lightly treat the laws laid down by Vitruvius and his followers at the revival of the arts, for we may be assured that in most cases they are not empirical, but founded on proper principles. We cannot, however, leave this point without giving another reason, which is conclusive against Chambers's construction of the passage; it is, that supposing the upper column's lower diameter to be the same or nearly so as the lower column's upper diameter, Fig. 914. if the fourth part had relation to the height instead of the bulk, we should have had the absurdity in the illustration above given, of an Ionic column in the second order only six and three quarters diameters high, whilst the lower or Doric is nine diameters in height. 2644. Scamozzi, we doubt not, thought as we have expressed ourselves on this subject, and we here translate the words he uses in the eleventh chapter of his sixth book (second part). “Hence it is more satisfactory, and they succeed better and are more pleasing to the eye, when these columns (the upper ones) are made according to their proper diminution, so that the lower part of the upper column may be just the thickness of the upper part of the lower one, and so from one to the other, as may be seen in the Ionic order of the Theatre of Marcellus and other edifices; and this is the reason and natural cause that it is the same as though out of a long and single tree the shafts were cut out one after the other.” 2645. The laws of solidity seem to require that where more than one order is used, the strongest is to occupy the lower situation; thus the Doric is placed on the Tuscan, the Ionic on the Doric, the Corinthian on the Ionic, and the Composite on the Corinthian; though, with respect to the last, we find examples of importance wherein the reverse has been the case. Two tiers of columns should not be of the same order, neither should an intermediate order be omitted; such, for instance, as placing the Ionic on the Tuscan column, or the Corinthian on the Doric; for by this practice many irregularities are introduced, especially in the details of the members. • **
2646. Frontwise the axes of the upper and lower columns must be in the same vertical plane, but viewed in flank this is not absolutely necessary; they should not, however, deviate too much from it. In the theatre of Marcellus the axes of the upper columns are nearly a foot within those of the Doric below them; but circumstances required this, and there is no great objection to the practice if the solidity of the structure be not lessened by it. Chambers observes that the retraction should never be greater than at the theatre of Marcellus, where the front of the plinth in the second order is in a line with the top of the shaft in the first. When the columns are detached, they should be placed centrally over each other, so that the axes of the upper and under ones may form one continued line, by which means solidity is gained as well as a satisfactory result to the eye. As to the false bearings of the bases of the upper order on the profile, this is a matter neither really affecting stability nor the appearance of the design.
2647. In England there are not many examples of orders above orders, while on the Continent the practice has not been uncommon; but it is always a matter of great difficulty so to arrange them as to avoid irregularities where triglyphs and modillions in the same design meet in the composition. We have used the figures of Chambers for our illustration here, because they are nearly coincident with the rules of Vitruvius and Scamozzi, and we shall now place them before the reader, observing that the irregularities alluded to are almost altogether avoided.
2648. Fig. 915. exhibits the Doric over the Tuscan order. The intervals A, B, and C are respectively 24,4}, and 6 modules; and A, B, and C’, 3, 5}, and 8 modules of their order. The entablature of the lower order is 3' modules, the column, including base and capital, being 14 modules high; and the entablature of the upper order is 4 modules high, the column with its base and capital being 16 modules in height. 2649. The distribution of the Doric and Ionic orders is given in fig. 916., wherein the intervals A, B, and C are respectively 3, 5}, and 8 modules; D, 7 module; and A, B, C, and D respectively 4, 7, 10, and 11 modules. The Doric order in this example is 20 modules high, whereof 4 are assigned to the entablature; the Ionic 22 modules high, whereof 4 belong to the entablature, 2650. In fig. 917. is represented the Corinthian above the Ionic order; the intervals A, B, C, D are respectively 5, 6, 7, and 1 modules, and those of A, B, C, D respectively 6-4, 7-6, 8.8, 1:6 modules; the lower order is 224 modules high, 18 being given to the column with its base and capital; and the upper or Corinthian order is 243 modules high, whereof 20 belong to the height of the column, including its base and capital. 2651. The last (fig. 918.) is of the Corinthian order above and Composite below. In the lower order the intervals A, B, C, D are 43, 6, 7, and 1 modules respectively, and A, B, C, and D, in the upper order, 6, 7-6, 8.8, and 1.6 modules respectively. The whole height of the Corinthian order is 25 modules, whereof 5 are given to the entablature; the Composite order here is 24 modules, of which 20 belong to the column, including the base and capital. 2652. We insert the observations of Chambers relative to the above four figures, which,
Fig. 917. Fig. 918.
as we have adopted them, shall be in his own words. “Among the intercolumniations there are some in the second orders extremely wide, such as the Ionic interval over the Doric araeostyle; the Composite and Corinthian intervals over the Ionic and Composite aracostyle, which, having a weak meagre appearance, and not being sufficiently solid, excepting in small buildings, are seldom to be suffered, and should seldom be introduced. The most eligible are the eustyle and diastyle for the first order, which produce nearly the diastyle and araeostyle in the second.” Speaking of the use of pedestals in orders above orders, the author thus proceeds: – “Many architects, among which number are Palladio and Scamozzi, place the second order of columns on a pedestal. In compositions consisting of two stories of arcades this cannot be avoided, but in colonnades it may and ought; for the addition of the pedestal renders the upper ordonnance too predominant, and the projection of the pedestal's base is both disagreeable to the eye and much too heavy a load on the inferior entablature. Palladio, in the Barbarano palace at Vicenza, has placed the columns of the second story on a plinth only, and this disposition is best; the height of the plinth being regulated by the point of view, and made sufficient to expose to sight the whole base of the column. In this case the balustrade must be without either pedestals or half balusters to support its extremities, because these would contract and alter the form of the column; its rail or cap must be fixed to the shafts of the columns, and its base made level with their bases; the upper torus and fillet of the columns being continued in the interval, and serving as mouldings to the base of the balustrade. The rail and balusters must not be clumsy; wherefore it is best to use double-bellied balusters, as Palladio has done in most of his buildings, and to give the rail a very little projection, that so it may not advance too far upon the surface of the column, and seem to cut into it. In large buildings the centre of the baluster may be in a line with the axis of the column; but in small ones it must be within it, for the reason just mentioned. The height of the balustrade is regulated in a great measure by its use, and cannot well be lower than three feet, nor should it be higher than three and a half or four feet. Nevertheless, it must necessarily bear some proportion to the rest of the architecture, and have nearly the same relation to the lower order, or whatever it immediately stands upon, as when a balustrade is placed thereon chiefly for ornament. Wherefore, if the parts are large, the height of the balustrade must be augmented, and if they are small it must be diminished; as is done in the Casino at Wilton, where it is only two feet four inches high, which was the largest dimension that could be given to it in so small a building. But that it might, notwithstanding its lowness, answer the intended purpose, the pavement of the portico is six inches lower than the bases of the columns, and on a level with the bottom of the plat-band that finishes the basement.” We must here leave this subject, recommending the student to an intimate acquaintance with the various examples that have been executed, and further advising him to test each of the examples that may fall under his notice by the principles first adverted to in this section, as the only true means of arriving at a satisfactory result.
2653. As the disposition of one arcade upon another is, under certain regulations, subject to the same laws of voids and solids as the simple arcade of one story, which has formed the subject of a previous section, we shall no further enter into the rules of its combination than to offer a few general observations on the matter in question; and herein, even with the reproach of a want of originality, we shall draw largely on our much-quoted author, Chambers, whose language and figures we are about to use. So sound, indeed, is the doctrine of Chambers in this respect, and so well founded on what has been done by those whom we consider the greatest masters, that we should not be satisfied without transferring his dicta to these pages, and that without any alteration. 2654. “The best,” says Chambers, “and, indeed, the only good disposition for two stories of arcades, is to raise the inferior order on a plinth, and the superior one on a pedestal, as Sangallo has done at the Pallazzo Farnese; making both the ordonnances of an equal height, as Palladio has done at the Basilica of Vicenza.” 2655. “Scamozzi, in the thirteenth chapter of his sixth book, says that the arches in the second story should not only be lower, but should also be narrower, than those in the first; supporting his doctrine by several specious arguments, and by the practice, as he says, of the ancient architects in various buildings mentioned by him. In most of these, however, the superior arches are so far from being narrower, that they are either equal to or wider than the inferior ones. In fact, his doctrine in this particular is very erroneous, entirely contrary to reason, and productive of several bad consequences; for if the upper arches be narrower than the lower ones, the piers must of course be broader, which is opposite to all rules of solidity whatever, and exceedingly unsightly. The extraordinary breadth of the pier on each side of the columns in the superior order is likewise a great deformity; even when the arches are of equal widths it is much too considerable. Palladio has, in the Carità at Venice, and at the Palazzo Thiene in Vicenza, made his upper arches wider than the lower ones, and I have not hesitated to follow his example; as by that means the weight of the solid in the superior order is somewhat diminished, the fronts of the upper piers bear a good proportion to their respective columns, and likewise to the rest of the composition.” 2656. “In a second story of arcades there is no avoiding pedestals. Palladio has, indeed, omitted them at the Carità, but his arches there are very ill proportioned. The extraordinary bulk and projection of these pedestals are, as before observed, a considerable defect; to remedy which in some measure they have been frequently employed without bases, as in the theatre of Marcellus, on the outside of the Palazzo Thiene, and that of the Chiericato in Vicenza. This, however, helps the matter but little; and it will be best to make them always with bases of a moderate projection, observing at the same time to reduce the projection of the bases of the columns to ten minutes only, that the die may be no larger than is absolutely necessary; and in this case particular care must be taken not to break the entablature over each column of the inferior order, because the false bearing of the pedestal in the second order will by so doing be rendered far more striking, and in reality more defective, having then no other support than the projecting mouldings of the inferior cornice. There is no occasion to raise the pedestals of the second order on a plinth, for as they come very forward on the cornice of the first order, and as the point of view must necessarily be distant, a very small part only of their bases will be hid from the eye.” 2657. “The balustrade must be level with the pedestals supporting the columns; its rail or cornice and base must be of equal dimensions, and of the same profile with theirs. It should be contained in the arch and set as far back as possible, that the form of the arch may appear distinct and uninterrupted from top to bottom; for which reason, likewise, the cornice of the pedestals must not return nor profile round the piers, which are to be contained in straight perpendicular lines from the imposts to the bases of the pedestals. The back of the rail may either be made plain or sunk into a panel in form of an open surbase, for so it will be most convenient to lean upon, and it should be in a line with or somewhat recessed within the backs of the piers. The back part of the balustrade may be adorned with the same mouldings as the bases of the piers, provided they have not much projection; but if that should be considerable, it will be best to use only a plinth crowned with the two upper mouldings, that so the approach may remain the more free." 2658. In fig. 919, is a Doric above a Tuscan arcade, from the example given by Chambers, whereon, before giving the dimensions of the different parts, we shall merely observe of it that the voids or arcades themselves are in round numbers to the solids as 295 to 205, being vastly greater. We are inclined to think that the voids in this case are rather too great in volume, and that had they been reduced to one half exactly, the