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Many of these gave proof of great skill and ingenuity plan of which is before you, its suitability for future Interon the part of their authors, but not one of them was national Exhibitions has been kept steadily in view, and thought to be perfectly adapted for the purpose. A Com-it has a much more permanent character than the famous mittee for all matters relating to the building, composed Crystal Palace erected for the 1851 Exhibition. of some of the leading architects and engineers of the day, It differs therefore from its predecessor in many essenwas nominated, and they prepared a plan which was, in a tial particulars. It is more commodious, more imposing great measure, a combination and modification of the in its interior, more varied, more suitable for Exhibition most meritorious designs furnished by the competitors. purposes, while from without its aspect is of impressive You have a drawing of this before you. It was actually magnitude and grandeur. determined on by the Committee, and very nearly carried out, but the popular outcry against it was so strong, that the Commission was glad enough to give it up at the last moment, to consider the happy suggestion of Sir Joseph Paxton, which they ultimately adopted, and the beautiful Crystal Palace (now removed, with some alteration, to Sydenham) was the result. This, as it appeared in 1851, you will at once recognise among the various drawings submitted to your inspection. Four years later came the Paris Universal Exhibition, of which you will also see a drawing of the permanent portion now remaining, to the same scale as that of 1851; and, finally, we have several beautiful views, prepared by some of the leading artists of the day, of our building as it will appear next year; I need not enumerate them, the various points from which they are taken being marked against each.

THE SITE.

You will better understand a description of the site by observing the plan of it, which is before you. The ground on which the main building stands is about 16 acres in extent, and occupies the southern portion of the land purchased at South Kensington by the Commissioners for the Exhibition of 1851. Nearly rectangular in shape, it measures about 1,200 feet from east to west, by 560 feet from north to south. It is immediately south of the Royal Hor ticultural Society's gardens, the southern arcade of which has been lent to the Exhibition for refreshment rooms. The Cromwell-road forms the southern boundary; on the east it adjoins Exhibition-road; and on the west, Prince Albert's-road.

The whole of this ground will be covered by buildings of a permanent character, and, to secure as much additional space as possible, the two long strips of ground between the east and west arcades and the adjacent roads will be roofed in by means of temporary sheds, to give ample space for the exhibition of machinery and other ponderous objects, which cannot be conveniently shown in the main building. The additional area afforded by these two annexes will be about seven acres, which will make the total extent of the Exhibition 24 acres.

The general level of the ground is from four to six feet below the adjoining roads, and it has a gentle slope from north-east to south-west. The nature of the soil is well adapted to building purposes; a bed of gravel, from four to twelve feet from the surface, extends throughout the whole area, so that a dry and firm foundation is easily obtained.

Here glass and iron are no longer the main features of the design, but are succeeded by lofty walls of brickwork, which surround the ground on all sides, and form the walls of the fine arts galleries. The east end and west sides, by being continued past the southern arcade of the gardens, have a frontage of 750 feet, and that on the south is 1,150 feet. The north front is the lower arcade of the gardens, which is having a permanent upper story added to it. The interior space thus enclosed is entirely covered in by roofs of various heights, and is divided into nave, transepts, aisles, and open courts; the latter, occupying comparatively a very small portion, are roofed with glass as in 1851, but the other parts have opaque roofs, and are lighted by clerestory windows.

The interior supports are hollow cast-iron columns, as in 1851, of somewhat larger dimensions, being a foot wide, with half an inch of metal in them. They are so arranged as to come at intervals of 25 or 50 feet from centre to centre; in fact, 25 is the unit here as 24 was in 1851, and you will find nearly all the leading dimensions, both vertical and horizontal, to be multiples of that number. The exceptions to this rule are the nave and transepts, which are 85 feet wide; the former runs east and west, and terminates in the centre of those fronts, having its central line 81 feet north of the centre line of the building; the latter extend north and south from the ends of the nave throughout the whole width. At the intersection of the nave and transepts are the great domes. The aisles are continued all round the nave and transepts, and the space enclosed by them forms the open or glass courts.

The columns are supported differently from what they were in 1851. On that occasion they were attached to connecting pieces, which, terminating in a large flat base plate, rested on concrete laid flush with the ground; these connecting pieces of course varied in height to suit the slope of the ground. This has been avoided in the present building by bedding the columns themselves on York slabs laid on brick piers, which are founded on concrete; the slabs being all adjusted to the same level throughout by varying the height of the brickwork, only one length of column is used, and the facility of setting them up is thus greatly increased.

At the north ends of the east and west fronts are the two annexes, temporary, supplementary structures, designed for the exhibition of machinery and other ponderous objects, which could not be conveniently placed in the main building.

The Commissioners for 1851 are the legal proprietors of The total area roofed in is 988,000 square feet; it is the site, but to secure the greater portion of it for the in- therefore, considerably larger than the 1851 Exhibition, tended 1872 Exhibition, they have agreed to reserve about which only occupied 799,000 square feet. It has also, 16 acres of it for that purpose on receiving £10,000 as a sort when actual covered space is alone considered, slightly the of ground rent. It is already agreed that to this Society advantage of the Paris Exhibition, which had a covered will be granted the lease of the central portion of the Pic-area of 953,000 square feet. But if we compare the total ture Gallery, one acre in extent, along the Cromwell-road, for 99 years, on condition that ground-rent to the amount of £240 per annum be paid to the 1851 Commissioners, it being understood that it will be given up unreservedly for the use of the 1872 Exhibition.

Unlike the 1851 Exhibition, therefore, the removal of which was compulsory, all that foresight could suggest has been done to retain the present buildings, and there can be no moral doubt that if, by any possible means, sufficient funds are available to meet the pecuniary liabilities, they will remain.

GENERAL DESCRIPTION.

space, covered and uncovered, occupied by each, Paris is considerably larger, for the better suitability of its climate for out of door display enabled the authorities of that Exhibition to increase the area of ground given up to exhibiting space by 547,000 square feet, while, with our variable climate, it has not been thought advisable to have more than 35,000 feet of ground unroofed; so that the total areas, covered and uncovered, occupied by the two Exhibitions, are 1,500,000 square feet for Paris, and 1,023,000 square feet for 1862.

The French Exhibition, therefore, considerably exceeded ours in size, but it was not nearly so compact in form, and its In the general design of the building, a large ground- temporary annexes made up a very large portion of it,

occupying 600,000 of the 953,000 square feet, while our two annexes do not amount to more than one-third of the total area.

I have prepared a diagram, showing the size of these three structures reduced to squares, which will show you at a glance the relative proportions of each.

CONTRACT.

time as part of the general front. The error has evidently arisen from the circumstance of the drawings in question having been made up by persons ignorant of the plan of the building, from geometric elevations, in which, of course, the domes appeared as if they belonged to the south front. I am induced to allude to this from the fact that much hostile criticism has been wasted upon the disastrous effect of the domes, as seen from positions, from Each dome keeps its which they are really invisible.

Before going into a more detailed account of the various parts thus generally described, it is desirable to state the means which Her Majesty's Commissioners have adopted place as the centre of its own front, and its effect is utterly for the punctual completion of this stupendous building. independent of its fellow, which is 1,000 feet from it. The plans were submitted to the competition of ten lead-To this want of comprehension of the subject may be ing contractors; three tenders were sent in, and that fur-attributed the feeling that has been expressed against. nished by Messrs. Kelk and Lucas being the lowest, was accepted.

These two most eminent firms, joining their resources together, have become partners for the work, and if one can judge from their antecedents, a better guarantee for punctuality and sound work could hardly have been ob

tained.

until seen from such a distance as to lose all connection

will be seen, on a little reflection, that each of the domes the two domes adopted, and in favour of a central one. It in the centre of the whole building would (from the vast is virtually central in its own composition, while a dome extent of the structure and its peculiar situation) have been thrown entirely out of sight on all sides but one, The nature of the contract is peculiar. The whole re- with the building in an architectural point of view. The sponsibility for the execution of the works rests with the upper terrace of the horticultural gardens is the only point contractors, and the amount they are to receive is contin- from which such a dome would have been seen in congent on the receipts of the Exhibition. The Commis-nection with the building, and this is also the only point sioners have the option of purchasing the building out and from which the two present domes appear simultaneously; out, or of merely paying for the use of it. For the rent but when thus viewed, so completely does the building of the building, a sum of £200,000 is guaranteed abso- carry on the symmetrical lines of arcades and terraces, that lutely; if the receipts exceed £400,000, the contractors the duality of the domes is at once accepted as the natural are to be paid £100,000 more for rent, and they are bound, complement of the system which has governed the laying if required, to sell the whole for a further sum of out of the entire quadrangle, namely, that it should be £130,000, thus making its total cost £430,000. considered with reference to a single building of commanding proportions, situated on the proper site for the chief point of the composition, the most northern and highest part of the ground.

The date agreed upon for the building to be completed and given up to the Commissioners is the 12th of February next, and although even now it is impossible to say, with certainty, whether that date will be rigidly adhered to, yet it is certain that, provided no unforeseen accident occurs, the stipulated time will be very nearly kept. Ample opportunity will thus be afforded for completing the arrangements of the interior by the 1st of May, on which day it will be opened to the public.

SOUTH FRONT.

The general outline of the south front presents an ele. vation 1,150 feet long, and 55 feet high in the brickwork, with two projecting towers at each end, rising 16 feet above the general outline, and a larger tower in the centre, in which is to be the main entrance to the Picture Galleries. Semicircular headed panels, separated by pilasters, are built at central intervals of 25 feet throughout the whole length, a high plinth extends all round, and between the arches are circular niches, at present vacant, but admitting of future decoration. In the lower portion of each panel is a window, to admit light and air to the ground floor, and for ventilation of the Picture Gallery above.

The exterior is chiefly in plain brickwork, and with no more ornament than that work admits of. The panels are plastered in cement, and experiments are proposed to ornament them in English mosaics. The exterior decoration will eventually depend on the way in which this is carried out, to be decided as funds become available; the present Exhibition will be quite incomplete in this respect, but any amount of architectural_ornament that can be paid for may be added hereafter. Yet, in spite of this want of ornament, the author of the design has succeedel, with comparatively very limited means, in producing a very imposing general effect.

Those who have become acquainted with the leading features of the Exhibition building, chiefly through the earlier published drawings, will perhaps be surprised at my describing the south, or principal front, without touching on the great domes, which, according to those drawings, form so important a feature in it. But the fact is that these domes, being 300 feet from this front, can never, in any way, enter into its effect; so far from it indeed, that from no possible position, can they ever be seen at the same

The main entrance to this portion of the building will be through three arches in the central tower, 20 feet wide and 50 feet high, resting on piers 14 feet thick, decorated with terra cotta columns. Above the arches is the cornice and frieze, on top of which, and above the middle porch, is an ornamental clock dial. Passing through the archways, the visitor enters a large vestibule and hall, 150 feet long and 110 feet wide, leading to the Industrial Courts and Galleries. A flight of steps on either side will conduct him to the Picture Galleries, before entering which I shall briefly explain the general principles which have influenced their design.

The chief desideratum of a picture gallery is an equally distributed light throughout, admitted in such a way as will prevent its rays being directly reflected from the surface of the picture to the eye of the visitor. A light, therefore, satisfying this condition, when the observer is standing at a convenient distance, is the only one which can be called perfect.

No one can have observed pictures lighted by ordinary windows without experiencing the unpleasant effect produced by the improper reflection of the rays, or glitter from the pictures, as it is called. It is for this reason that one is often puzzled where to find a place from which to see the whole of a large picture to advantage. This defect exists in many of the finest galleries, both in this country and on the Continent, and the result is that some pictures can scarcely be seen at all, while others can only be observed from one or two points, which are always more or less crowded, according to the merits of the subject.

This is obviated by admitting the light at a particular angle from the roof, by means of a skylight extending along its entire length, and which in the present case measures 31 feet in width, that is, 15' 6" from the ridge on either side. The entire width of the opening, measured on a horizontal plane, is 29' 2". As will be seen by reference to the section, each room is 50 feet wide, and at a height of 32' 9", a cove, springing from a cornice on either side, reaches the height of the tie bar of the principals (42' 10" above the floor), 12' 4" from the wall, thus leaving a space 25' 4" between the coves.

In this space a transparent calico ceiling (hereafter to be replaced by ground glass) is introduced, which, however, is raised 2' 4" above the highest point of the cove, or 45′ 7′′ from the floor. The space between the highest point of the cove and the eave of the calico is occupied by louvres for ventilation.

These proportions will afford the gallery as much light as possible, and glitter from the surface of the pictures will be avoided. As regards the quantity of light admitted, it may be briefly stated that the opening for admission is exactly half the floor area of the gallery, the former being 25 feet wide, the latter 50. In dealing with the quantity of light, another important point must not be lost sight of, namely, the height of the opening from the floor and its consequent distance from the picture. In this gallery this is reduced to a minimum consistently with the avoidance of glitter, being only 45' 7" from the floor.

This system of lighting increases the difficulty of successfully treating the exterior of the building, for it prevents any windows being placed in the upper part of the side walls, but after the very successful application of these principles of lighting to picture galleries which have been constructed within the last few years at South Kensington, it was wisely determined to forego all other considerations, and apply the same principles to the rooms destined to receive the choicest works of art of the present age.

On ascending the stairs, the visitor enters a vestibule of similar proportions to the one below, from which he obtains one unbroken vista throughout the whole extent of the main gallery, and it is difficult to conceive a finer effect than that produced by contemplating the noble proportions of the rooms before him.

The interior decorations of these rooms will be very simple, and may be briefly described as a plain cove extending to each side of the skylight, and resting on a moulded cornice.

Entering the first on either side, he will find himself in The following illustration will explain the question of a spacious hall, 325 feet long, 50 feet wide, and 43 feet glitter, or reflection of light, from the varnish of pic-high. Passing through this, he will enter one of the wing tures:-Supposing a mirror to be hung against the towers, which forms a room 52 feet by 45 feet, and 66 feet entire surface of the wall. It will be seen, by referring high; he will then enter another room 75 feet long, and to the diagram, that a ray of light from the skylight, at of the same width and height as the first, from which he its extremity furthest from either wall, striking that wall will pass into the end tower, whence he will have an unat A, at a height of 23′ 3′′ above the floor, will be interrupted view of the whole main gallery. reflected so as to reach the eye, at E, of a beholder (say 5'3" above the floor) standing 5' on the other side of the centre of the room, or 30 feet from the mirror, and consequently all the rays striking below that point will fall below his eye, or, in other words, he will not be able to see the image of the skylight in the mirror at any point below 23′ 3" from the floor, and, as a matter of course, there will be no glitter on the wall, or on pictures hung against it, below that point. Consequently, to see pictures without glitter hung higher up, it will be neressary for the spectator to retire still further from the centre of the gallery.

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Arrangements for thorough ventilation, so essential to the preservation of the pictures and comfort of the visitors, are amply provided for, by admitting fresh air through apertures along the floor level, and allowing the vitiated air to escape through louvres in the skylight.

Descending to the ground floor, the same sized rooms are repeated, but as they are lighted by means of ordinary windows they will probably be devoted to other objects than those coming under the head of fine arts. The part of the picture gallery which is to revert to the Society of Arts is the central hall, and the two large rooms, 325 feet long, on either side of it.

Before concluding this description of the Picture Gallery, its constructive details will be interesting. The foundations throughout are carried down to the gravel, here from 6 to 12 feet below the surface of the ground, in concrete, on which ordinary brick footings are laid. In the front wall the piers carrying the semi-circular arches are 12 feet wide, by 3' 2" thick, and the intervening 2Bpanel having merely its own weight to support, is only 9" work. The back wall is of rather a different construction. This is a plain wall from top to bottom, with numerous arches through it on the ground-floor; it is built for the most part hollow, with piers so placed that the weight of the floor and roof will come on them. This system of hollow walling gives the greatest strength with the least amount of material, and secures straight face at either side. The floor of the picture gallery has been constructed of great strength, so as to bear with perfect safety the greatest load which can be brought on it. It is carried on girders 134 by 12, resting on the side walls and intermediately supported by two cast-iron columns. These girders cross the building at central intervals of 12 feet, and over them are laid joists 11 in. by 24 in., two feet apart, to carry the floor-boards. A portion of this floor has been proved to 140 lbs. to the foot, which exceeds the greatest load it can have to bear when densely crowded with visitors. The walls in the picture gallery are lined throughout with wood, which is kept at a short distance from the brickwork, so as to guard against damp. The design of the roof is the same as that already employed by Captain Fowke in one of the South Kensington Galleries, and also in the Irish National Gallery in Dublin, and seems well adapted for its purpose; the principals which support it consist of two strongly trussed double timber rafters, connected together by an iron tie bar four feet above the level of the wall plate. The coved ceiling is thus made four feet higher than it

Transverse Section of Picture Gallery, showing the way of admitting the light to avoid glitter.

It will be seen from the diagram that this point, which is called the glitter point, alters with the position of the beholder. For instance, at E, 5 feet from the wall, the glitter point is at F, 11 feet from the floor, while on coming closer it will descend in proportion. On the other hand, by receding to a distance of 10 feet, the wall may be seen without glitter to a height of 14 feet. Looking again to the same diagram, it will be seen that, apart from all considerations of reflection, a person desiring to see a picture at a height of 14 feet, would naturally retire 10 feet, if not more from it, and the same may be said of the other heights and positions shown on the sectional diagram, so that in any position in which a person can conveniently examine a picture, he may be sure of having its surface free from glitter.

could have been with an ordinary tie-beam roof. As I am not aware that this description of truss is often adopted in a timber and ceiled roof, I am induced to show a drawing of it, as it is of extremely simple construction, and capable of very general application.

The principals are placed at central intervals of 25 feet; they rest on flat stones built into the walls, and strongly trussed purlins, carrying the skylight rafters and upper portion of the cove, are suspended to them. The skylight is glazed with 16 oz. glass, and the rest of the roof covered with slates. EAST AND WEST FRONTS.

We now come to the east and west fronts, which, though differing from the south, are not less imposing. They are, in all respects, similar to each other in their general effect. Here the stupendous domes, rising to a height of 260 feet, will show to most advantage, and the transept roof, with its lofty clerestory windows, will be in full view. To the observer below, the form of each dome will appear nearly that of a semicircle; this effect is obtained by making its height 11 feet more than its semi-diameter, which will fully allow for the loss by perspective diminution.

From the crown of the dome rises the finial to a height | of 55 feet. The dome is in the middle of each façade; its centre is the point formed by the intersection of the centre lines of the nave and transepts, and the front of the building is advanced from it 108 feet. Here, through a noble arched recess, is the main entrance to the industrial courts, the effect of which will, I think, form one of the most pleasing exterior parts of the building. This central porch is 162 feet in extreme width, and contains a deep semi-circular arched recess, of 68 feet span and 80 feet high. It is recessed with a deep covering capable of receiving an almost endless variety of decoration, if such be desired hereafter; while in its present simplicity, it is equally valuable on account of the richness of effect produced by the bold light and shade.

The main and auxiliary picture galleries of the fine arts department will afford 4,600 lineal feet of hanging space, from 17 to 30 feet high; yet all this amount, large as it may seem, is required, and even more would have been desirable, could it, by any possibility, have been obtained. An idea of their extent may be formed by the fact that in walking once up and down the galleries the visitor will have to traverse a mile all but 60 yards, and presuming the moderate allowance of 75 per cent. of the available wall-space to be actually covered by pictures, their aggregate areas will equal 7,600 square yards, or about 1 acres ! NORTH FRONT.

To complete our survey of the exterior, we must examine the north front, for which purpose it is necessary to enter the Royal Horticultural Society's Gardens. The large space here afforded admits of a connoisseur critisising it from several points of view. For our purpose, however, it will suffice to imagine our station to be on the central walk, one or two hundred yards from the South Arcade.

From no other point will a better appreciation of the building be obtained. The South Arcade forms the basement of the north front, to which an upper story is now being added. The façade is divided into two floors, except the central portion, which has a mezzanine interposed. The ground floor, consisting of the Southern Arcade of the Gardens, with its pleasing arrangement of twisted terra-cotta columns, is, doubtless, familiar to most of you. The whole front is divided into five faces, in different lines of advance. By subdividing the centre mass into three sections, a very great variety and relief of design is obtained. The middle of the front is occupied by the entrance from the gardens, through three 10-feet ornamented brick archways, supported by coupled stone columns; these are immediately opposite the Southern Entrance, from which point will be obtained one unbroken vista across the whole building up to the cascade and conservatory at the north end of the gardens.

In the tympan of the recess is the great rose window, which will be visible from end to end within, the window in one closing the vista as the spectator looks from a In examining the five divisions of the façade, we standing point beneath the other. Minor porches on find that the centre (70 feet high) presents three levels either side, 36 feet wide, forming wings, support a pedi--the arcade of the gardens-the shallow mezzanine mental gable which rises to a level with the ridge of the (interrupted by the central arches before mentioned)nave and transept roofs, and is finished with a bold line of and the upper floor. On each side of the centre are the balustrade. The entrances beneath are enclosed by an lights of the arcade, consisting of tripled ornamental brick arcaded framing filling up the recess for one-quarter of its arches, on terra-cotta columns, separated by pilasters; height, and having a balcony above. The flat brickwork of the upper lights are similarly arranged, and the whole the wings is relieved by pilasters, one on each side of the is surrounded by a paneled frieze of appropriate design, minor porch; these carry a light cornice moulding, sur- with openings for ventilation. Over this is seen the roof, mounted by an attic. of good pitch, following the line of the ground plan.

On either side of the central entrance, recessed 15 feet from it, extend 235 feet to the north and south, the exterior walls of the building; these enclose the auxiliary picture galleries. There is a high plinth from end to end, and immediately above are panels formed by a series of coupled semi-circular arched recesses with bold pilasters between. Over all is an appropriate cornice supported by corbels. By the wall being reduced to a height of 363 feet, the lofty clerestory windows of the transept which rise immediately behind, come into the composition. As in the south front, the lower portions of the panels are occupied by windows to give light and ventilation to the offices and retiring rooms, with which the ground floor on these sides will be occupied. The upper floor is to be used as an auxiliary picture gallery, and is therefore lighted on the same principles as the rooms on the south front.

A visitor will be able to enter the auxiliary galleries, independent of the main gallery, by means of stairs on either side of the east and west entrances; or he will have access to them from the end towers of the latter, already described. They form four distinct rooms, 247 feet long, 25 feet wide, and 17 feet high. The same principles of lighting and ventilating being observed in these galleries as in the larger one, their construction is similar, subject, of course, to the alterations necessitated by their smaller size.

The two corresponding recesses on each side are thrown back twenty-five feet, and extend in an unbroken line for 200 feet, with a height of 60 feet; the level of the upper floor here corresponds with that of the centre mezzanine, and the lighting, both above and below, is effected by eleven sets of tripled arches, similar to those in the centre division.

At each end are the returns into the garden, and in the fifty feet which completes the length, is an entrance archway, ten feet wide, on the far side of which the tripled arched light is repeated.

The treatment of the whole façade is most effective; much diversity is obtained by the arrangement of the masses; general uniformity is successfully sought, and every part harmonises admirably with the adjoining arcades. At a short distance behind rises the lofty ridge of the nave, terminated at either end by the imposing outline of the great domes.

The upper and lower floors on this front occupy an area of 26,800 square feet; the whole of this space is to be given up to the refreshment rooms and offices connected with them.

A better choice of situation could not have been made. The exhausted sight-seer, surfeited and bewildered by the endless variety of objects furnished by the Exhibition,

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will here retire to recruit his mental and bodily vigour for fresh exertions. Here will be retailed refreshments of all kinds-every variety of catables, from the delicate sponge-cake and strawberry ice to the honest substantial roast beef. The teetotaler will find himself bountifully supplied with waters-aerated, medicated, and pure, too numerous to mention; or, should he be so disposed, he may even indulge in ginger-beer and lemonade, while the more generous liver will obtain anything he chooses to call for from bitter ale to iced champagne.

The angles over the haunches and crown of the arch are firmly braced together, so as to reduce the thrust as much as possible.

The rib is repeated 30 times in the length of the nave, and from its graceful curve and elegant lightness it produces an extremely fine effect. Between every roof principal is a clerestory light 25 feet high, consisting of three arches springing from intermediate mullions. The roof is covered with felt, on 14 inch plank, which is laid diagonally so as to brace the whole together. The nave is therefore entirely dependent for its light on the clerestory windows; this is found to be amply sufficient, and a substantial water-tight covering is thus ensured, having the advantage of obviating all chance of that unpleasant glare which the experience of 1851 proved to be unavoidable with a summer and warmer in winter. The rain-water from the roof is conducted, by means of gutters, down the columns supporting the ribs to drains laid under the ground floor, which carry it off to the drains under the adjoining roads.

Let us glance at the mental refreshment afforded; on ordinary days it will be the quiet contemplation of the fairy-like scene before him; here will the mind feast, while the eye wanders from the sloping green banks, and verdant alleys of the pleasure gardens, studded with flowers basking in the sun, to where the great cascade-glass covering, while at the same time it will be cooler in appropriate monument to the parent of all around-pours itself into its wide and glittering basin below. On the occasion of fêtes, the beauty of the scene will be still further increased by throngs of gaily dressed visitors to the gardens, and the enjoyment of it enhanced by the music provided for their entertainment.

Nor will the pleasure ever be clouded by thoughts of the possibility of these rooms being removed, for no matter what are the financial results of the Exhibition, they, at least, will remain after its close, and form part of the Horticultural Gardens.

NAVE AND TRANSEPTS.

Let us now begin our survey of the interior.

In this it is not my intention to go minutely into the construction of the whole, and I shall only dwell on those parts which present any novelties; the limited time at our disposal necessitates this, and even were it otherwise, it would be unprofitable, for there are certain portions without any claim to novelty, a description of which would be uninteresting, as they differ in no essential point from many ordinary iron structures.

To commence with the nave and transepts, which are similar in all respects.

Entering by the east or west front, the visitor rises two steps, which brings him to the level of the dais under each dome. From this point, six feet above the rest of the floor, he will in one view command the interior of the whole building. A very serious obstacle in the ground has been cleverly overcome by this arrangement. The roads surrounding the site are about five feet above the level of the ground on which the building stands. Had this contour been rigidly followed, the visitor would have had on entering at once to descend five feet.

From each end of the nave, at right angles to it, and extending north and south for a length of 650 feet, run the transepts. They are the same width and height as the nave, and the ribs of its roof are of precisely the same construction. This construction will be more fully understood by referring to the drawing, which shows the arrangement of planks and bracing.

The nave ribs have been made at Mr. Kelk's yaid in Pimlico, and carted to the ground in four pieces. When on the spot ready for hoisting, they were formed into two pieces so arranged that the point of junction should always be at the ridge. To fix the principals in the nave roof, a moveable scaffold of very clever design was used. A drawing of it, showing its construction, is before you. It contains 4,740 cubic feet of timber, and weighs 87 tons; but, notwithstanding this, it is moved by four men working crowbars under the wheels. One half of a rib was first hoisted to its place; when in position, the other half was raised, and as soon as both were fixed true, they were joined together by completing the arch and bracing over its crown. soon as one rib was up, the travelling scaffold was moved to the adjoining bay, and the next rib completed. The purlins and boarding were then fixed, after which the scaffold was again moved forward, and another bay covered in the same manner.

As

The hoisting is all done by a most ingenious winch, or hoist, worked by steam, the invention of Mr. Ashton. This machine has two grooved cast-iron barrels, which are made to revolve by means of a system of toothed wheels, connected with a portable steam engine. A rope is passed This immediate descent would have been most incon-round the grooves. On the fall being manned, and the venient, and would have totally marred the otherwise barrels set in motion, the coils of the rope are gathered up, imposing interior aspect of the building. Had the whole and a great hoisting power obtained. By means of snatch area been raised to suit the road level, it will be obvious blocks and pulleys, ropes are led from this beautifully that the cost would have been considerably increased. simple machine to all parts of the building, and the From the dais three flights of steps, 80 feet wide, con- heaviest materials, such as girders, columns, scaffold beams, duct the visitor into the nave and transept on either side. &c., are hoisted to their position with the greatest ease and The nave is 800 feet long, 85 feet wide, and 100 feet rapidity. As an instance, I need only mention that the high to the ridge of the roof. heavy floor girders, weighing about 1 tons, were raised in two minutes, columns in about the same time, and the ponderous ribs of the nave, weighing 6 tons, required only from ten to twenty minutes to raise them their full height.

The supports on either side consist of square and round cast-iron columns, coupled together; the former carry the gallery floor, and the latter, advancing into the nave, receives the principals of the roof. These columns are 50 feet high, in two lengths of 25 feet each, and from their capitals spring the roof frames, which consist of three thicknesses of plank, from 18" to 2' 6" deep, firmly nailed and bolted together, and so arranged that their ends break joint. The centre plank is 4 inches thick, and each of the outer ones is 3 inches; the lower edges are tangents to an imaginary semi-circle, round which they form half of a nearly regular polygon. From the springing rise the posts of the clerestory windows, 25 feet high. The principal rafters of the roof frames rise from the top of these posts, and are carried up after passing a tangent to the extrados of the arch to meet at the ridge in a point 25 feet above the top of the clerestory.

The only portion of the Crystal Palace of 1851 which can be compared with the nave is the great central transept, whose height was 104 feet, or 4 feet more than that of the nave, but it was narrower by 13 feet, being only 72 feet wide, while the total length of the nave of the present building will be very nearly three times as great.

The ribs of the transept were fixed over a standing scaffold all through, which alone consumed 30,336 cubic feet of timber. The reason for this was that as the domes divide the transepts into four separate lengths, four travellers would have been necessary, and though these would not have taken nearly so much material as the standing scaffolds, yet the contractors thought that the difference

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