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CHAPTER IX.
THE CAPITAL.
Оглавление§ I. The reader will remember that in Chap. VII. § V. it was said that the cornice of the wall, being cut to pieces and gathered together, formed the capital of the column. We have now to follow it in its transformation.
We must, of course, take our simplest form or root of cornices (a, in Fig. V., above). We will take X and Y there, and we must necessarily gather them together as we did Xb and Yb in Chap. VII. Look back to the tenth paragraph of Chap. VII., read or glance it over again, substitute X and Y for Xb and Yb, read capital for base, and, as we said that the capital was the hand of the pillar, while the base was its foot, read also fingers for toes; and as you look to the plate, Fig. XII., turn it upside down. Then h, in Fig. XII., becomes now your best general form of block capital, as before of block base.
§ II. You will thus have a perfect idea of the analogies between base and capital; our farther inquiry is into their differences. You cannot but have noticed that when Fig. XII. is turned upside down, the square stone (Y) looks too heavy for the supporting stone (X); and that in the profile of cornice (a of Fig. V.) the proportions are altogether different. You will feel the fitness of this in an instant when you consider that the principal function of the sloping part in Fig. XII. is as a prop to the pillar to keep it from slipping aside; but the function of the sloping stone in the cornice and capital is to carry weight above. The thrust of the slope in the one case should therefore be lateral, in the other upwards.
§ III. We will, therefore, take the two figures, e and h of Fig. XII., and make this change in them as we reverse them, using now the exact profile of the cornice a—the father of cornices; and we shall thus have a and b, Fig. XIX.
Fig. XIX.
Both of these are sufficiently ugly, the reader thinks; so do I; but we will mend them before we have done with them: that at a is assuredly the ugliest—like a tile on a flower-pot. It is, nevertheless, the father of capitals; being the simplest condition of the gathered father of cornices. But it is to be observed that the diameter of the shaft here is arbitrarily assumed to be small, in order more clearly to show the general relations of the sloping stone to the shaft and upper stone; and this smallness of the shaft diameter is inconsistent with the serviceableness and beauty of the arrangement at a, if it were to be realised (as we shall see presently); but it is not inconsistent with its central character, as the representative of every species of possible capital; nor is its tile and flower-pot look to be regretted, as it may remind the reader of the reported origin of the Corinthian capital. The stones of the cornice, hitherto called X and Y, receive, now that they form the capital, each a separate name; the sloping stone is called the Bell of the capital, and that laid above it, the Abacus. Abacus means a board or tile: I wish there were an English word for it, but I fear there is no substitution possible, the term having been long fixed, and the reader will find it convenient to familiarise himself with the Latin one.
§ IV. The form of base, e of Fig. XII., which corresponds to this first form of capital, a, was said to be objectionable only because it looked insecure; and the spurs were added as a kind of pledge of stability to the eye. But evidently the projecting corners of the abacus at a, Fig. XIX., are actually insecure; they may break off, if great weight be laid upon them. This is the chief reason of the ugliness of the form; and the spurs in b are now no mere pledges of apparent stability, but have very serious practical use in supporting the angle of the abacus. If, even with the added spur, the support seems insufficient, we may fill up the crannies between the spurs and the bell, and we have the form c.
Thus a, though the germ and type of capitals, is itself (except under some peculiar conditions) both ugly and insecure; b is the first type of capitals which carry light weight; c, of capitals which carry excessive weight.
§ V. I fear, however, the reader may think he is going slightly too fast, and may not like having the capital forced upon him out of the cornice; but would prefer inventing a capital for the shaft itself, without reference to the cornice at all. We will do so then; though we shall come to the same result.
The shaft, it will be remembered, has to sustain the same weight as the long piece of wall which was concentrated into the shaft; it is enabled to do this both by its better form and better knit materials; and it can carry a greater weight than the space at the top of it is adapted to receive. The first point, therefore, is to expand this space as far as possible, and that in a form more convenient than the circle for the adjustment of the stones above. In general the square is a more convenient form than any other; but the hexagon or octagon is sometimes better fitted for masses of work which divide in six or eight directions. Then our first impulse would be to put a square or hexagonal stone on the top of the shaft, projecting as far beyond it as might be safely ventured; as at a, Fig. XX. This is the abacus. Our next idea would be to put a conical shaped stone beneath this abacus, to support its outer edge, as at b. This is the bell.
Fig. XX.
§ VI. Now the entire treatment of the capital depends simply on the manner in which this bell-stone is prepared for fitting the shaft below and the abacus above. Placed as at a, in Fig. XIX., it gives us the simplest of possible forms; with the spurs added, as at b, it gives the germ of the richest and most elaborate forms: but there are two modes of treatment more dexterous than the one, and less elaborate than the other, which are of the highest possible importance—modes in which the bell is brought to its proper form by truncation.
§ VII. Let d and f, Fig. XIX., be two bell-stones; d is part of a cone (a sugar-loaf upside down, with its point cut off); f part of a four-sided pyramid. Then, assuming the abacus to be square, d will already fit the shaft, but has to be chiselled to fit the abacus; f will already fit the abacus, but has to be chiselled to fit the shaft.
From the broad end of d chop or chisel off, in four vertical planes, as much as will leave its head an exact square. The vertical cuttings will form curves on the sides of the cone (curves of a curious kind, which the reader need not be troubled to examine), and we shall have the form at e, which is the root of the greater number of Norman capitals.
From f cut off the angles, beginning at the corners of the square and widening the truncation downwards, so as to give the form at g, where the base of the bell is an octagon, and its top remains a square. A very slight rounding away of the angles of the octagon at the base of g will enable it to fit the circular shaft closely enough for all practical purposes, and this form, at g, is the root of nearly all Lombardic capitals.
If, instead of a square, the head of the bell were hexagonal or octagonal, the operation of cutting would be the same on each angle; but there would be produced, of course, six or eight curves on the sides of e, and twelve or sixteen sides to the base of g.
Fig. XXI.
§ VIII. The truncations in e and g may of course be executed on concave or convex forms of d and f; but e is usually worked on a straight-sided bell, and the truncation of g often becomes concave while the bell remains straight; for this simple reason—that the sharp points at the angles of g, being somewhat difficult to cut, and easily broken off, are usually avoided by beginning the truncation a little way down the side of the bell, and then recovering the lost ground by a deeper cut inwards, as here, Fig. XXI. This is the actual form of the capitals of the balustrades of St. Mark’s: it is the root of all the Byzantine Arab capitals, and of all the most beautiful capitals in the world, whose function is to express lightness.
§ IX. We have hitherto proceeded entirely on the assumption that the form of cornice which was gathered together to produce the capital was the root of cornices, a of Fig. V. But this, it will be remembered, was said in § VI. of Chap. VI. to be especially characteristic of southern work, and that in northern and wet climates it took the form of a dripstone.
Accordingly, in the northern climates, the dripstone gathered together forms a peculiar northern capital, commonly called the Early English,47 owing to its especial use in that style.
There would have been no absurdity in this if shafts were always to be exposed to the weather; but in Gothic constructions the most important shafts are in the inside of the building. The dripstone sections of their capitals are therefore unnecessary and ridiculous.
§ X. They are, however, much worse than unnecessary.
Fig. XXII.
The edge of the dripstone, being undercut, has no bearing power, and the capital fails, therefore, in its own principal function; and besides this, the undercut contour admits of no distinctly visible decoration; it is, therefore, left utterly barren, and the capital looks as if it had been turned in a lathe. The Early English capital has, therefore, the three greatest faults that any design can have: (1) it fails in its own proper purpose, that of support; (2) it is adapted to a purpose to which it can never be put, that of keeping off rain; (3) it cannot be decorated.
The Early English capital is, therefore, a barbarism of triple grossness, and degrades the style in which it is found, otherwise very noble, to one of second-rate order.
§ XI. Dismissing, therefore, the Early English capital, as deserving no place in our system, let us reassemble in one view the forms which have been legitimately developed, and which are to become hereafter subjects of decoration. To the forms a, b, and c, Fig. XIX., we must add the two simplest truncated forms e and g, Fig. XIX., putting their abaci on them (as we considered their contours in the bells only), and we shall have the five forms now given in parallel perspective in Fig. XXII., which are the roots of all good capitals existing, or capable of existence, and whose variations, infinite and a thousand times infinite, are all produced by introduction of various curvatures into their contours, and the endless methods of decoration superinduced on such curvatures.
§ XII. There is, however, a kind of variation, also infinite, which takes place in these radical forms, before they receive either curvature or decoration. This is the variety of proportion borne by the different lines of the capital to each other, and to the shafts. This is a structural question, at present to be considered as far as is possible.
Fig. XXIII.
§ XIII. All the five capitals (which are indeed five orders with legitimate distinction; very different, however, from the five orders as commonly understood) may be represented by the same profile, a section through the sides of a, b, d, and e, or through the angles of c, Fig. XXII. This profile we will put on the top of a shaft, as at A, Fig. XXIII., which shaft we will suppose of equal diameter above and below for the sake of greater simplicity: in this simplest condition, however, relations of proportion exist between five quantities, any one or any two, or any three, or any four of which may change, irrespective of the others. These five quantities are:
1. The height of the shaft, a b;
2. Its diameter, b c;
3. The length of slope of bell, b d;
4. The inclination of this slope, or angle c b d;
5. The depth of abacus, d e.
For every change in any one of these quantities we have a new proportion of capital: five infinities, supposing change only in one quantity at a time: infinity of infinities in the sum of possible changes.
It is, therefore, only possible to note the general laws of change; every scale of pillar, and every weight laid upon it admitting, within certain limits, a variety out of which the architect has his choice; but yet fixing limits which the proportion becomes ugly when it approaches, and dangerous when it exceeds. But the inquiry into this subject is too difficult for the general reader, and I shall content myself with proving four laws, easily understood and generally applicable; for proof of which if the said reader care not, he may miss the next four paragraphs without harm.
§ XIV. 1. The more slender the shaft, the greater, proportionally, may be the projection of the abacus. For, looking back to Fig. XXIII., let the height a b be fixed, the length d b, the angle d b c, and the depth d e. Let the single quantity b c be variable, let B be a capital and shaft which are found to be perfectly safe in proportion to the weight they bear, and let the weight be equally distributed over the whole of the abacus. Then this weight may be represented by any number of equal divisions, suppose four, as l, m, n, r, of brickwork above, of which each division is one fourth of the whole weight; and let this weight be placed in the most trying way on the abacus, that is to say, let the masses l and r be detached from m and n, and bear with their full weight on the outside of the capital. We assume, in B, that the width of abacus e f is twice as great as that of the shaft, b c, and on these conditions we assume the capital to be safe.
But b c is allowed to be variable. Let it become b 2 c 2 at C, which is a length representing about the diameter of a shaft containing half the substance of the shaft B, and, therefore, able to sustain not more than half the weight sustained by B. But the slope b d and depth d e remaining unchanged, we have the capital of C, which we are to load with only half the weight of l, m, n, r, i.e., with l and r alone. Therefore the weight of l and r, now represented by the masses l 2, r 2, is distributed over the whole of the capital. But the weight r was adequately supported by the projecting piece of the first capital h f c: much more is it now adequately supported by i h, f 2 c 2. Therefore, if the capital of B was safe, that of C is more than safe. Now in B the length e f was only twice b c; but in C, e 2 f 2 will be found more than twice that of b 2 c 2. Therefore, the more slender the shaft, the greater may be the proportional excess of the abacus over its diameter.
Fig. XXIV.
§ XV. 2. The smaller the scale of the building, the greater may be the excess of the abacus over the diameter of the shaft. This principle requires, I think, no very lengthy proof: the reader can understand at once that the cohesion and strength of stone which can sustain a small projecting mass, will not sustain a vast one overhanging in the same proportion. A bank even of loose earth, six feet high, will sometimes overhang its base a foot or two, as you may see any day in the gravelly banks of the lanes of Hampstead: but make the bank of gravel, equally loose, six hundred feet high, and see if you can get it to overhang a hundred or two! much more if there be weight above it increased in the same proportion. Hence, let any capital be given, whose projection is just safe, and no more, on its existing scale; increase its proportions every way equally, though ever so little, and it is unsafe; diminish them equally, and it becomes safe in the exact degree of the diminution.
Let, then, the quantity e d, and angle d b c, at A of Fig. XXIII., be invariable, and let the length d b vary: then we shall have such a series of forms as may be represented by a, b, c, Fig. XXIV., of which a is a proportion for a colossal building, b for a moderately sized building, while c could only be admitted on a very small scale indeed.
§ XVI. 3. The greater the excess of abacus, the steeper must be the slope of the bell, the shaft diameter being constant.
This will evidently follow from the considerations in the last paragraph; supposing only that, instead of the scale of shaft and capital varying together, the scale of the capital varies alone. For it will then still be true, that, if the projection of the capital be just safe on a given scale, as its excess over the shaft diameter increases, the projection will be unsafe, if the slope of the bell remain constant. But it may be rendered safe by making this slope steeper, and so increasing its supporting power.
Fig. XXV.
Thus let the capital a, Fig. XXV., be just safe. Then the capital b, in which the slope is the same but the excess greater, is unsafe. But the capital c, in which, though the excess equals that of b, the steepness of the supporting slope is increased, will be as safe as b, and probably as strong as a.48
§ XVII. 4. The steeper the slope of the bell, the thinner may be the abacus.
The use of the abacus is eminently to equalise the pressure over the surface of the bell, so that the weight may not by any accident be directed exclusively upon its edges. In proportion to the strength of these edges, this function of the abacus is superseded, and these edges are strong in proportion to the steepness of the slope. Thus in Fig. XXVI., the bell at a would carry weight safely enough without any abacus, but that at c would not: it would probably have its edges broken off. The abacus superimposed might be on a very thin, little more than formal, as at b; but on c must be thick, as at d.
Fig. XXVI.
§ XVIII. These four rules are all that are necessary for general criticism; and observe that these are only semi-imperative—rules of permission, not of compulsion. Thus Law 1 asserts that the slender shaft may have greater excess of capital than the thick shaft; but it need not, unless the architect chooses; his thick shafts must have small excess, but his slender ones need not have large. So Law 2 says, that as the building is smaller, the excess may be greater; but it need not, for the excess which is safe in the large is still safer in the small. So Law 3 says that capitals of great excess must have steep slopes; but it does not say that capitals of small excess may not have steep slopes also, if we choose. And lastly, Law 4 asserts the necessity of the thick abacus for the shallow bell; but the steep bell may have a thick abacus also.
§ XIX. It will be found, however, that in practice some confession of these laws will always be useful, and especially of the two first. The eye always requires, on a slender shaft, a more spreading capital than it does on a massy one, and a bolder mass of capital on a small scale than on a large. And, in the application of the first rule, it is to be noted that a shaft becomes slender either by diminution of diameter or increase of height; that either mode of change presupposes the weight above it diminished, and requires an expansion of abacus. I know no mode of spoiling a noble building more frequent in actual practice than the imposition of flat and slightly expanded capitals on tall shafts.
§ XX. The reader must observe, also, that, in the demonstration of the four laws, I always assumed the weight above to be given. By the alteration of this weight, therefore, the architect has it in his power to relieve, and therefore alter, the forms of his capitals. By its various distribution on their centres or edges, the slope of their bells and thickness of abaci will be affected also; so that he has countless expedients at his command for the various treatment of his design. He can divide his weights among more shafts; he can throw them in different places and different directions on the abaci; he can alter slope of bells or diameter of shafts; he can use spurred or plain bells, thin or thick abaci; and all these changes admitting of infinity in their degrees, and infinity a thousand times told in their relations: and all this without reference to decoration, merely with the five forms of block capital!
§ XXI. In the harmony of these arrangements, in their fitness, unity, and accuracy, lies the true proportion of every building—proportion utterly endless in its infinities of change, with unchanged beauty. And yet this connexion of the frame of their building into one harmony has, I believe, never been so much as dreamed of by architects. It has been instinctively done in some degree by many, empirically in some degree by many more; thoughtfully and thoroughly, I believe, by none.
§ XXII. We have hitherto considered the abacus as necessarily a separate stone from the bell: evidently, however, the strength of the capital will be undiminished if both are cut out of one block. This is actually the case in many capitals, especially those on a small scale; and in others the detached upper stone is a mere representative of the abacus, and is much thinner than the form of the capital requires, while the true abacus is united with the bell, and concealed by its decoration, or made part of it.
§ XXIII. Farther. We have hitherto considered bell and abacus as both derived from the concentration of the cornice. But it must at once occur to the reader, that the projection of the under stone and the thickness of the upper, which are quite enough for the work of the continuous cornice, may not be enough always, or rather are seldom likely to be so, for the harder work of the capital. Both may have to be deepened and expanded: but as this would cause a want of harmony in the parts, when they occur on the same level, it is better in such case to let the entire cornice form the abacus of the capital, and put a deep capital bell beneath it.
Fig. XXVII.
§ XXIV. The reader will understand both arrangements instantly by two examples. Fig. XXVII. represents two windows, more than usually beautiful examples of a very frequent Venetian form. Here the deep cornice or string course which runs along the wall of the house is quite strong enough for the work of the capitals of the slender shafts: its own upper stone is therefore also theirs; its own lower stone, by its revolution or concentration, forms their bells: but to mark the increased importance of its function in so doing, it receives decoration, as the bell of the capital, which it did not receive as the under stone of the cornice.
In Fig. XXVIII., a little bit of the church of Santa Fosca at Torcello, the cornice or string course, which goes round every part of the church, is not strong enough to form the capitals of the shafts. It therefore forms their abaci only; and in order to mark the diminished importance of its function, it ceases to receive, as the abacus of the capital, the decoration which it received as the string course of the wall.
This last arrangement is of great frequency in Venice, occurring most characteristically in St. Mark’s: and in the Gothic of St. John and Paul we find the two arrangements beautifully united, though in great simplicity; the string courses of the walls form the capitals of the shafts of the traceries; and the abaci of the vaulting shafts of the apse.
Fig. XXVIII.
§ XXV. We have hitherto spoken of capitals of circular shafts only: those of square piers are more frequently formed by the cornice only; otherwise they are like those of circular piers, without the difficulty of reconciling the base of the bell with its head.
§ XXVI. When two or more shafts are grouped together, their capitals are usually treated as separate, until they come into actual contact. If there be any awkwardness in the junction, it is concealed by the decoration, and one abacus serves, in most cases, for all. The double group, Fig. XXVII., is the simplest possible type of the arrangement. In the richer Northern Gothic groups of eighteen or twenty shafts cluster together, and sometimes the smaller shafts crouch under the capitals of the larger, and hide their heads in the crannies, with small nominal abaci of their own, while the larger shafts carry the serviceable abacus of the whole pier, as in the nave of Rouen. There is, however, evident sacrifice of sound principle in this system, the smaller abaci being of no use. They are the exact contrary of the rude early abacus at Milan, given in Plate XVII. There one poor abacus stretched itself out to do all the work: here there are idle abaci getting up into corners and doing none.
§ XXVII. Finally, we have considered the capital hitherto entirely as an expansion of the bearing power of the shaft, supposing the shaft composed of a single stone. But, evidently, the capital has a function, if possible, yet more important, when the shaft is composed of small masonry. It enables all that masonry to act together, and to receive the pressure from above collectively and with a single strength. And thus, considered merely as a large stone set on the top of the shaft, it is a feature of the highest architectural importance, irrespective of its expansion, which indeed is, in some very noble capitals, exceedingly small. And thus every large stone set at any important point to reassemble the force of smaller masonry and prepare it for the sustaining of weight, is a capital or “head” stone (the true meaning of the word) whether it project or not. Thus at 6, in Plate IV., the stones which support the thrust of the brickwork are capitals, which have no projection at all; and the large stones in the window above are capitals projecting in one direction only.
§ XXVIII. The reader is now master of all he need know respecting construction of capitals; and from what has been laid before him, must assuredly feel that there can never be any new system of architectural forms invented; but that all vertical support must be, to the end of time, best obtained by shafts and capitals. It has been so obtained by nearly every nation of builders, with more or less refinement in the management of the details; and the later Gothic builders of the North stand almost alone in their effort to dispense with the natural development of the shaft, and banish the capital from their compositions.
They were gradually led into this error through a series of steps which it is not here our business to trace. But they may be generalised in a few words.
§ XXIX. All classical architecture, and the Romanesque which is legitimately descended from it, is composed of bold independent shafts, plain or fluted, with bold detached capitals, forming arcades or colonnades where they are needed; and of walls whose apertures are surrounded by courses of parallel lines called mouldings, which are continuous round the apertures, and have neither shafts nor capitals. The shaft system and moulding system are entirely separate.
The Gothic architects confounded the two. They clustered the shafts till they looked like a group of mouldings. They shod and capitaled the mouldings till they looked like a group of shafts. So that a pier became merely the side of a door or window rolled up, and the side of the window a pier unrolled (vide last Chapter, § XXX.), both being composed of a series of small shafts, each with base and capital. The architect seemed to have whole mats of shafts at his disposal, like the rush mats which one puts under cream cheese. If he wanted a great pier he rolled up the mat; if he wanted the side of a door he spread out the mat: and now the reader has to add to the other distinctions between the Egyptian and the Gothic shaft, already noted in § XXVI. of Chap. VIII., this one more—the most important of all—that while the Egyptian rush cluster has only one massive capital altogether, the Gothic rush mat has a separate tiny capital to every several rush.
§ XXX. The mats were gradually made of finer rushes, until it became troublesome to give each rush its capital. In fact, when the groups of shafts became excessively complicated, the expansion of their small abaci was of no use: it was dispensed with altogether, and the mouldings of pier and jamb ran up continuously into the arches.
This condition, though in many respects faulty and false, is yet the eminently characteristic state of Gothic: it is the definite formation of it as a distinct style, owing no farther aid to classical models; and its lightness and complexity render it, when well treated, and enriched with Flamboyant decoration, a very glorious means of picturesque effect. It is, in fact, this form of Gothic which commends itself most easily to the general mind, and which has suggested the innumerable foolish theories about the derivation of Gothic from tree trunks and avenues, which have from time to time been brought forward by persons ignorant of the history of architecture.
§ XXXI. When the sense of picturesqueness, as well as that of justness and dignity, had been lost, the spring of the continuous mouldings was replaced by what Professor Willis calls the Discontinuous impost; which, being a barbarism of the basest and most painful kind, and being to architecture what the setting of a saw is to music, I shall not trouble the reader to examine. For it is not in my plan to note for him all the various conditions of error, but only to guide him to the appreciation of the right; and I only note even the true Continuous or Flamboyant Gothic because this is redeemed by its beautiful decoration, afterwards to be considered. For, as far as structure is concerned, the moment the capital vanishes from the shaft, that moment we are in error: all good Gothic has true capitals to the shafts of its jambs and traceries, and all Gothic is debased the instant the shaft vanishes. It matters not how slender, or how small, or how low, the shaft may be: wherever there is indication of concentrated vertical support, then the capital is a necessary termination. I know how much Gothic, otherwise beautiful, this sweeping principle condemns; but it condemns not altogether. We may still take delight in its lovely proportions, its rich decoration, or its elastic and reedy moulding; but be assured, wherever shafts, or any approximations to the forms of shafts, are employed, for whatever office, or on whatever scale, be it in jambs or piers, or balustrades, or traceries, without capitals, there is a defiance of the natural laws of construction; and that, wherever such examples are found in ancient buildings, they are either the experiments of barbarism, or the commencements of decline.
47 Appendix 19, “Early English Capitals.”
48 In this case the weight borne is supposed to increase as the abacus widens; the illustration would have been clearer if I had assumed the breadth of abacus to be constant, and that of the shaft to vary.