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SECTION OF HENRY VII's, CHAPEL. 6 inches, and the clear width of the nave 33 feet. The entire width, at the basement or level of the pavement of the crypt, is 79 feet : 264 feet, or ș, is devoted to points of support, and 527 feet, or ș, to the side aisles and nave; the area of a severy shows f applied to walls and piers, and to the void, which proportions accord with the early rather than with the late examples ; the great weight of the vaulting, which is 62 feet high from the pavement of the chapel, requiring additional strength, the proportions of St. George's Chapel at Windsor would not have been equal to the necessary resistance. (See par. 2002w.)
Our limits will not permit a more extended inquiry into the principles of proportion, the study of which is calculated to produce an important improvement in the noble art, for the practice of which the young architect must prepare himself by careful measurement, not only of the ruins of the Acropolis and of the Capitol, but of all that remains of mediæval architecture: he must be a pilgrim seeking after truth, not bowing before any favourite shrine, but returning with a devotion as enlarged as his subject. The stupendous works which antiquity has transmitted to us, it is hoped, may excite the attention of the general reader, nor will his interest be diminished by the contemplation of the astonishing development of modern industry. The writer cannot but feel the importance and variety of his subject, and, while he is conscious of his own imperfections, he must often accuse the deficiency of his materials: but the results of his labour, however inadequate to his own wishes, he finally delivers to the candour of the public.
The FIGURE OF THE CUBE has from time immemorial been selected by the architect and engineer as best suited for every variety of edifice; and it is remarkable that the multiplying of the cube constitutes the design of the Greek temple, the Gothic cathedral, and the modern iron structure at Sydenham, the variety of effect depending upon the mode of its application. Reviewing the temples of the ancients, we find that those composed of a portico of four columns, and six intercolumniations on the flank, or seven columns; that the whole constituted a double cube, or two cubes side by side. A cube of 32 feet 4 inches in height, breadth, and length, placed behind another of the same dimensions, would represent the entire mass of the temple of Fortuna Virilis at Rome.
The temple of six columns, or the Hexastyle, is composed of nine half cubes, or three entire, placed one behind the other, with the addition of three half cubes against the sides of the first, making altogether four cubes and a balf.
The Octastyle temple is composed of nine whole cubes, or four cubes and a half in depth, repeated twice, placed side by side. The Parthenon is thus formed of cubes, whose sides each measure 50 feet 6 inches; two occupy the front, of 101 feet; the depth of the four and a half cubes are a trifle more than 227 feet, the true extent being 227 feet 7 inches.
Six cubes, placed one above the other, form the design of the Campanile, at Florence, commenced by the celebrated Giotto in the year 1334 ; and on the breaking up of these cubes into ornament, the perpendicular lines are lengthened out, whilst in the Greek temple the horizontal are made to preponderate; repose in the latter, and lofty aspiration in the former, marks the distinction between them.
The Tower of Rochester Castle, usually supposed to be of Norman construction, perfectly resembles the far-famed Coliseum at Rome, in the manner in which the spiral vaults are executed, and in the general method adopted in carrying up the massive walls. The cement employed was evidently manufactured on the spot, as it is entirely composed of the materials found close at hand, and the stone such as could be brought down the Medway, and quarried on its shores. If this enduring structure was the work of Gundulph in the 12th century, we have the strongest evidence that the Roman arts of construction were continued without any change either in the art or mystery of building up to that period at least.
The building is a cube and a half nearly, being about 74 feet square without the en. trance porch, and its height to the top of the angular turrets is 112 feet. A square divided into twenty-five equal squares exhibits its plan ; the sixteen outer squares represent the thickness of the walls, in which are galleries, recesses, and contrivances necessary for its protection against an enemy; the nine inner squares of the plan are divided into two spacious rooms, one being 45 feet by 19 feet, the other 45 feet by 21 feet; the wall that divides thein is 5 feet 6 inches in thickness. The height comprises a basement story and three others beneath its roof, which has been vaulted, and which is 90 feet to the top of the battlement, and 112 feet to the top of the turrets.
Rules adopted by the Freemasons in setting out their Buildings, from the Tenth to the Fifteenth Century :
In the foregoing remarks on Proportion some general rules have been suggested as to mass and void, and more particularly the principles of setting out the windows and tracery of the English and French cathedrals. On referring again to this interesting subject, the writer was led to inquire why the structures of the latter country should be so uniformly larger than those of the former, from which they differed but little in style, preserving the same relative proportions, though differing in dimensions. Guided by the supposition that the buildings of the above period were the works of fraternities of freemasons, it seemed conclusive that they should have some standard of measurement, either of their own or peculiar to each country; and, on testing the measurements with that view, it resulted that those of England were set out with the English perch of 16 feet 6 inches, and no doubt by an English. lodge; while in those of France the French perch royal, of 22 pieds du roi, equal to 23:452 English feet, was employed; the few exceptions at Bayeux, Caen, St. George Bocherville, and some others with round arches, and the elegant church of St. Ouen at Rouen, in the flamboyant style, are set out with the English perch of 16 feet 6 inches, and are universally attributed to English constructors; they certainly most curiously agree in proportion and dimension with the English cathédrals, which have two cubes given to the nave, producing on the plan a Latin cross, instead of the Greek so usually found in France. It would sem that the standard measures referred to were well and wisely chosen, as if intendid to apply to all times and all varieties of structure ; for it is singular how nearly the dimensions of the cubes of the fairy palace at Sydenham, 24 feet, correspond to 23 feet 6 inches of the royal French perch,
To illustrate this subject fully is not within our present narrow limits ; a very few examples must suffice, out of the numbers which might be adduced in support of the proposition; and it is earnestly hoped that the young architect may be sufficiently into
rested to test the theory practically, that while he admires their picturesque beauties, be will examine by measurement their plans and sections.
of the French Cathedrals, we must be content to refer to Chartres, Reims, and Amiens as those most admired, and which serve as examples of the application of the French perch in setting out their various parts as well as the whole.
Chartres Cathedral, in which the pointed arch first appears, is a structure of the 11th century, and one of the most remarkable, as well as beautiful, erected after the first introduction of the pointed style by those who had journeyed with the Crusaders, and had an opportunity of studying their craft in the East.
The proportions are simple in the extreme. A cube is devoted to the nave, two to the transept, one to the choir ; in addition to which, at the eastern extremity, is a semicircular termination with six polygonal chapels attached, forming on the plan a Greek cross of admirable design.
The nave, comprising six divisions of pointed arches on each side, is in its length and width six royal perches, the distribution of which will enable the reader to comprehend the setting out of the entire plan, which he can refer to in several publications.
The clear width of the nave is two royal perches between the clerestory walls; each side aisle is one royal perch, and the distance from the middle of one pier to that of the other, froin west to east, is also a royal perch.
The entire width of the nave from out to out, that is to say, from the face of the exterior buttresses, is six royal perches, four perches being given to the two side aisles and nave for their clear widths, and the other two to the projection of the buttresses, thickness of the two outer walls, and those of the clerestory of the nave.
If the royal perch be divided into three, one part constitutes the diameter given to the pillars, and another the thickness of each of the walls of the side aisles.
The internal height of the nave is the same as its clear internal width with side aisles ; so justly is all proportioned that the perch royal, and its division into three, enables us to comprehend the dimensions of the parts, as well as that of the entire mass of construction.
Reims Cathedral was similarly set out. The clear width of the nave is two royal perches, and each of the side aisles is one perch. The extreme width of the nave, comprising the projection of the buttresses, is six royal perches; the diameter of the piers, one-third of a royal perch, as in the example of Chartres.
It must be observed that the dimensions do not apply to the clear distances between the pillars, but to the space between the walls, which in the clerestory are peculiar for the contrivances of a gallery, which usually continues around the entire cathedral, and which will be better understood when we treat upon Amiens Cathedral, reserved for a fuller description. That the percii was the standard of measurement there can be no doubt; for in the smaller churches of Great Britain, as that of Roslyn, for example, the nave is a single perch in width, and the side aisles half a pereh; the proportions of the parts being also those of the third of an English perch.
Salisbury Cathedral, a contemporary strueture with Amiens, is set out with the English perch, and affords the best commentary upon the two standard measures made use of in the same century by the French and English freemasons.
The Nave of Amiens Cathedral is usually admired for its elegant proportions, and by several eminent critics has been cited as the beau ideal of that style of architecture so universally practised during the middle ages, or after the Romanesque had been discontinued. It is one of the most simple in its arrangement, though at first sight, removing all idea of simplicity, and appearing so complicated from its variety of parts, as to defy the application of any ordinary rules; the numerous arcades, the narrow and lofty compartments, the vaulted divisions, the diagonal and curved lines, blending one into the other, and apparently without limit, it is some time before the eye can acquiesce in the idea that such an edifice can be brought under the same laws as a Greek temple, or that the cube could be the measure of its parts or its whole. In taking the measurements, however, of this rare example, the dimension of 2.3 feet 6 inches so frequently occurred that it seemed to denote a standard by which to arrive at the length, breadth, and height of the whole, and that if considered after the manner of Sebastian Serlio. where he describes Bramante's plan of St. Peter's, we might arrive at something like a clue to the whole design.
It is curious to note, in the work of the above mentioned architect, several allusions to the cube, in the defining the parts as well as the whole of a design, and there can be little doubt that this simple figure served as the means of measuring the quantities, of either solid or void, in every period of the constructive arts; certainly none presents to the architect a better means of comprehending or of measuring quantity, and none is more readily subdivided, or rendered subservient to the taste of the designer, whatever may be the architecture he is anxious to imitate,
Within an isometrical cube may be placed the entire nave of Amiens Cathedral; and the etter to understand its proportions, we must suppose each square or cube into which it is
divided to measure 28 feet 6 inches each side, or the isometrical figure to contain 216 such cubes ; the total height, width, and length being 141 feet, or six times the 28 feet 6 inches. (See fig. 1927.)
On the plan are six divisions in length and width, or altogether 36 squares ; each measure 23 feet 6 inches on each of their sides. The six outer divisions of the principal figure are devoted to walls and buttresses ; the adjoining six on each side allow the situation
of the side aisles ; and the two middle divisions that of the nave. The two side aisles occupy together 12 squares, as does the nave; the remaining 12 being devoted to outer walls and their buttresses.
The entire area, therefore, has 24 squares to represent its interior distribution, and half that number its external walls; or one-third walls, two-thirds void. Such are the general arrangements of its plan, and its extreme simplicity has enabled the constructors to execute the vaulting of the side aisles and that of the centre nave by diagonal ribs, which in the former extend over one square, and in the latter two, thus giving to the nave its due pro portion of height, without changing the principle of its construction.
The freemasons of the middle ages were so perfectly acquainted with geometry that there is seldom any defect in their vaulting; it is evident that they laid down their plans for its execution before they decided upon the form of their main piers; in their setting out, every part had its due function ; and the column, which was intended to be connected with the vaulting, either of nave or side aisle, was peculiarly adapted by its position for its use.
The master mason Robert de Luzarche commenced the building of this nave about the year 1220, the founder being Bishop Evrard. The pillars of the nave were raised to the height of their capitals in 1236, but it was not till 1236 that the vaulting was completed; and about eight or nine years afterwards the lateral chapels were added.
To the top of the battlement of the nave there is not quite so much height as the outer wall of the Coliseum at Rome, which is 157 feet; but it is curious to observe that one division of this renowned building does not differ very materially in its proportions from that at Amiens ; the division of the ampitheatre being seven cubes in height; the piers occupy one third of the width of a compartment, as is usual in Roman structures of the same period. The masonry of Amiens Cathedral is executed after the Roman models, consequently the pointed arch makes the chief difference between the two styles.
To render the application of the theory of the cube to the nave of Amiens Cathedral more evident, or how the 216 cubes which the isometrical figure contains are placed, somewhat more of detail must be entered into.
The six main divisions shown in the figure, with the side aisle behind them, have their points of support at the four angles of each of the six squares; then each square, with its 23 feet 6 inches sides, shows the position of the lowest cube of the six placed one above the other, forming the entire height of each division or severy.
At the top of the second cube is the level upon which the main arches spring, and that upon which the ribs of the vaulting of the side aisles rest.
The top of the third cube indicates the level upon which the triforium is based, and consequently contains the vaulting of the side aisle.
The fourth cube is the triforium, and the fifth and the sixth the clerestory.
On examining the section, the side aisles are three cubes in height, including the vaulting, and the nave six ; the entire open space of the interior has 18 cubes for each aisle, or 36 for the two side aisles, and 72 for the nave; in all 108 cubes, or exactly one half the entire number contained in the isometrical cube.
It must be remarked that considerable alterations bave been made since the building was constructed; between the buttresses, chapels have been formed, and the original windows, which lighted the side aisles, removed to the extent, or somewhat beyond the outer face of buttresses, as represented. The interior is therefore increased materially in width, and its effect greatly improved, making the entire internal width and height more in conformity with each other, or each 141 feet.
In the elevation of the divisions the boundary of each of the six cubes is more clearly marked. The width from centre to centre of each pillar, indicated by the seven circles (fig. 1328.) is 23 feet 6 inches; to the top of the capitals from the pavement A B, the height is twice that dimension ; to the bottom of the bases of the column of the triforium B C, the same; thence to the bottom of the glass of the clerestory windows C D, the same; to the tops of the capitals or spring of the arches D E, the same ; and above that line to the underside the vaulting E F, the same; thus, six times 23 feet 6 inches, or 141 feet, is the total height from the pavement, of the division represented in fig. 1328.
As the groined vaults of the side aisles are set Fig. 1328. out upon a re, and the width from the centres of piers is the same as those towards the