Hoisting the Ribs for the Transept Roof.Hoisting the Ribs for the Transept Roof.
Hoisting the Ribs for the Transept Roof.
Hoisting the Ribs for the Transept Roof.
"There was a peculiar difficulty to be overcome in this operation, which arose from the circumstance that the width of the framework was greater than that of the transept, the extreme width of the framework to be hoisted being seventy-four feet, and the clear width apart of the trusses above which it had to be hoisted being only seventy-one feet four inches. It was therefore necessary to raise one side to a height of thirty-five feet before raising the other, so as to diminish the horizontal width of the whole, the diameter of the semicircle being maintained at this angle; the whole was then hoisted, until the highest end could clear the tramway."
This accounts for the slanting position in which the ribs are shown in the view given.
"The foot of the ribs on one side was then passed over the tramway sufficiently to allow the other side to clear the opposite truss; after which the whole was hoisted to the full height, and rested on rollers of hard wood placed between the sills attached to the framework and the tramway, by means of which it was moved to its permanent position. There it was again raised by another set of shears, while the sill and tramway were removed from under it; and the ribs were then lowered into the sockets prepared for them, formed by the continuation of the columns above the level of the lead-flat."
"Each successive pair of ribs was fixed at a distance of twenty-four feet, or one bay from the preceding one; and the purlins, &c., were fixed in the intervening space without any scaffolding from the ground, by means of jointed ladders, which were adjusted to the form of the roof."
The first pair of ribs was hoisted December 4th, and the eighth pair on December 12th. The operation, which was one of great excitement and considerable anxiety, was personally superintended by the contractors, aided by their most able foremen and assistants; and a crowd of visitors, including many of the illustrious promoters of the undertaking, watched with intense interest the steady ascent of the apparently unwieldy piece of construction, and every spectator seemed astonished at the mechanical regularity with which the whole operation proceeded. It took about one hour to raise a pair from the ground to the level of the lead-flat, and the whole was done without any accident whatever. About sixty men were employed in the hoisting, there being eleven men to each crab, and the remainder on the lead-flats.
Glazing the Transept Roof.
THE semicircular form of the transept roof rendered it necessary to adopt a different mode of operation for glazing it to that used in the horizontal portion. A stage, thirty-two feet long and about three feet wide, with a protecting rail at the side, was constructed, so that it rested upon rollers, travelling on the ridges. It was slung by ropes from the crown of the arched roof, and could be raised and lowered at pleasure. It accommodated eight workmen, with the necessary quantity of materials in sash-bars and glass; and they thus performed, with ease and rapidity, an operation which before the fitting-up of the stage appeared at least extremely difficult, and to the uninitiated next to impossible.
STAGE FOR GLAZING THE ROOF OF TRANSEPT.STAGE FOR GLAZING THE ROOF OF TRANSEPT.
STAGE FOR GLAZING THE ROOF OF TRANSEPT.
STAGE FOR GLAZING THE ROOF OF TRANSEPT.
The men commenced fixing the glass at the bottom or springing of the arch, and as they completed their work the stage was raised at intervals by labourers stationed on the lead-flat. A portion of the glazing at the crown of the arch was effected by men working on a light scaffold, suspended within from the temporary ties mentioned as having been attached to the ribs; whilst those upon the stage worked upwards till they joined the portion done from the top.
The Painting.
APORTION of the work which necessarily occupied a very large amount of time was the painting, which was necessary for the preservation of all the parts, as well as for their appearance; and when it is considered that every portion required to be gone over four times, it must be evident that it was highly desirable to adopt some meansfor facilitating the operation. It was found that the sash-bars of the roof, being in short lengths and of small dimensions, could readily be operated upon by some mechanical contrivance.
THE SASH-BAR PAINTING-MACHINE.THE SASH-BAR PAINTING-MACHINE.
THE SASH-BAR PAINTING-MACHINE.
THE SASH-BAR PAINTING-MACHINE.
A wooden trough was made sufficiently long to receive the sash-bars, and this was filled with paint; a number of the bars were then put into it, and upon being taken out separately, they were passed through a frame into which a set of brushes were fixed in such a manner as to clear off all the unnecessary paint. Two small brushes, placed where the bar first entered the frame, cleared out the grooves. One workman pushed the bar in at one end of the frame, which was about two feet six inches long, and another drew it out at the other end, where a trough was placed to receive any droppings of paint. The bars were then stacked upright, until they were sufficiently dry for the next coat. The first coat only was put on by this apparatus, the second being done in the ordinary manner, and the last not till after the work was all fixed in its place. By means of this apparatus a workman could perform at least ten times the amount of work done in the ordinary way.
THE FRAME-WORK WITH BRUSHES.THE FRAME-WORK WITH BRUSHES.
THE FRAME-WORK WITH BRUSHES.
THE FRAME-WORK WITH BRUSHES.
The finishing the painting of the various parts of the roof internally, after they had been put together, was very ingeniously managed, so that while the workmen were able to work with ease to themselves, the scaffolding on which they stood required no supports from the ground, where they would have been much in the way of other operations; loops ofwrought-iron were hooked on to the roof-trusses, and by means of these a perfect cloud of scaffold-boards was suspended, enabling between 400 and 500 men to be at work at one time. The roof of the main avenue, particularly, presented a very singular appearance, as nearly one half of the entire length was thus covered at one time, and a crowd of painters were at work over the heads of many, perhaps unconscious exhibitors, who were arranging their goods undisturbed below.
The Hand-rail Machine.
ONE of the mechanical contrivances which were put up on the ground during the works, for saving labour and increasing the rapidity of production, remains to be mentioned; it was contrived for turning out the rounded mahogany hand-rail for the gallery railing as well as that for the staircases.
The mahogany being supplied in slabs of the requisite thickness, these were first cut up by circular saws into pieces of a square section, and the angles of these were then bevelled off by the same means; the lengths were afterwards transferred to the hand-rail cutting machine to be rounded.
THE HAND-RAIL CUTTING MACHINE.THE HAND-RAIL CUTTING MACHINE.
THE HAND-RAIL CUTTING MACHINE.
THE HAND-RAIL CUTTING MACHINE.
PART OF HAND-RAIL MACHINE.PART OF HAND-RAIL MACHINE.
PART OF HAND-RAIL MACHINE.
PART OF HAND-RAIL MACHINE.
The principal portion of the machine consists of a hollow cast-iron cylinder, round which a strap may be passed to drive it. At one end of this cylinder four cutters are fixed, so that a piece of wood passing between them and through the cylinder, as it revolves, is rounded off to a true circular form of section, and is turned out so smoothlyfinished as to require scarcely any further work upon it before fixing. In advance of the cutters pressure-rollers are placed, furnished with teeth; and these, as they are turned round by a cranked handle, seize upon a piece of mahogany and force it forward against the cutters, which form, as it were, the jaws of the hollow cylinder, which thus seems to be constantly swallowing lengths of rough mahogany, which escape from it finished. The wooden rail is passed up to the cutters along a groove, the end of which is shown in the small engraving; and opposite each end of the revolving cylinder springs are fixed, which prevent the rail from shifting its position. The hand-rail was all turned out in 21-feet lengths, of which about thirty were completed in the day.
General View of the Works.
WE have mentioned that the actual commencement of the building was made by fixing one of the columns on the 26th of September; and, within a few weeks, more than a thousand men were at work, though, from the great extent of the ground they were spread over, it was difficult to estimate their number, which was, however, made apparent by the rapidity with which the building began to grow. The place presented an animated and interesting scene, which attracted a great number of visitors; and crowds of the fair sex were not deterred by the rough state of the ground from endeavouring to satisfy their proverbial thirst for knowledge. In one part of the ground might be seen the putting together of the wrought-iron roof-girders to the deafening tune of more than a hundred hammers; in another place gutters were being put together by the mile, for which some hundred or two of sawyers were cutting up ship-loads of timber. Three portable steam-engines in various parts were driving the different machinery already described, which, however, was mostly grouped in one place near the transept. The central avenue formed, of course, the great thoroughfare, where teams of horses were constantly passing, dragging the slender columns, or unwieldy-looking girders, to their places, while other teams were engaged in running them up to their final position. Over-head, too, the glaziers' waggons, dotted about the roof, seemed to be running on some new aerial railways; in every direction that the eye turned the busy scene extended.
For carrying on these extensive works an immense number of men were necessarily employed on the spot, besides those occupied in preparing the various parts at different places. The greatest number of men on the ground in any one week was 2,260; and the season of the year frequently rendered it necessary for the workmen to continue their labours after dark,which they did partly by the light of huge bonfires of shavings and odd scraps of wood. The effect of these great fires, which were generally lighted in some part of the main avenue, was exceedingly grand. The light of the tall flames was reflected from the glass of the roof far away into the darkness which concealed all the other parts; whilst occasionally a lantern carried by a workman engaged in fixing the upper columns, or some part of the roof, glimmered like some new star.
On one occasion, when the greatest efforts were being made to push on the progress of the works, no less than twelve large bonfires lighted the men at their midnight toil; and had the building been formed of combustible materials, a passing observer would have imagined that the whole was in flames.
Paying the Workmen.
THE process of distributing their wages among so large a number of men, on every recurring Saturday evening, was one which could only be effected within a reasonable time by some systematic arrangement; and to such perfection was this brought in the course of the works, that the whole number of 2,000 men or upwards were sometimes paid in little more than an hour; though at first it occupied a considerably longer time.
The mode in which this was effected was as follows:—When a workman was engaged his name was entered in a book against a certain number, which was stamped on several brass tickets, three of which were given to each workman before leaving the ground in the evening.
THE BRASS TICKETS AND MONEY-BOX.THE BRASS TICKETS AND MONEY-BOX.
THE BRASS TICKETS AND MONEY-BOX.
THE BRASS TICKETS AND MONEY-BOX.
Every man had to enter the premises three times in the course of the day; namely, the first thing in the morning, after returning from breakfast, and after returning from dinner. On each occasion he was required to deposit at the gate one of these tickets, which were afterwards sorted by the clerks, and entered in the time-book. In this way, if a man failed to come to his work, his ticket would be missing, and the time during which he was absent would not be entered; a corresponding amount being deducted from his week's wages.
On the Saturday, each man's time was made up from the book; and hiswages calculated accordingly, and the amount entered against his name. The money due to each man was then counted out and placed in a small tin box, with a ticket, on which was written the man's name and number, and the amount of wages paid to him.
THE INTERIOR OF THE PAY-OFFICE.THE INTERIOR OF THE PAY-OFFICE.
THE INTERIOR OF THE PAY-OFFICE.
THE INTERIOR OF THE PAY-OFFICE.
All this was done in the time-keeper's office, which was conveniently placed near the entrance to the works. When all the preliminary arrangements had been completed, the workmen's bell was rung, and they assembled (a motley and sometimes clamorous crowd) round the pay-office, which was provided with two small openings through which the payments were made.
THE MEN TAKING THEIR WAGES AT THE PAY-OFFICE.THE MEN TAKING THEIR WAGES AT THE PAY-OFFICE.
THE MEN TAKING THEIR WAGES AT THE PAY-OFFICE.
THE MEN TAKING THEIR WAGES AT THE PAY-OFFICE.
Two men stationed outside the office then called over the numbers of the workmen, who presented themselves, in the order in which they were called, at the pay-windows, where each man took the small box passed out to him with the money, and left the box in passing out at the gate. If any man considered the amount of wages paid to him not correct, he presented the ticket given to him with the wages at the office on the Monday morning following, when the matter was arranged by the time-keeper.
THE WORKMEN WAITING TO BE PAID.THE WORKMEN WAITING TO BE PAID.
THE WORKMEN WAITING TO BE PAID.
THE WORKMEN WAITING TO BE PAID.
Any person acquainted with the irregular habits of vast numbers of our workmen, who will often be absent from their work a quarter of a day, and at other times a whole day, thus varying the amount of wages due at the end of the week to almost every man, will at once see that, without a well-arranged system, such as that described, the payment of so large a body of men would have occupied as many days as it really did hours. The engravings annexed, in illustration of this part of our subject, will convey to the reader some idea of the scene we have endeavoured to describe, though it must fall far short of the picturesque reality.
General Statistics.
IT is with great pleasure that we are able to mention that, notwithstanding the difficult character of some of the work, and the extreme rapidity with which it was carried on, very few accidents of importance occurred; a circumstance which must be ascribed to the great care taken by the contractors for the safety of the men while engaged in their work: and in the cases where the accidents that occurred were of a serious or fatal kind, their origin was mostly to be traced to a neglect of those precautions which the men were constantly urged and ordered to take.
A few statistics of the quantities of different parts of the work not already mentioned will complete this portion of our subject. The whole amount of iron-work in the building is stated at about 4000 tons; and about 1,200 loads of timber were required for the wood-work. There are 2,941 trussed gutters in the roof, and 1,495 glazed sashes were required to inclose the sides of the building. As many as 316 iron girders were cast, in one week, and 442 lengths of the Paxton's gutters were cut out by the machinery in the same time. No less than 18,392 squares of glass, containing 62,508 feet superficial, or about one-and-a-half acres, were also fixed in one week.
It may be further mentioned that the weight of the different parts forming the flat ridge-and-furrow roofing amounts to three-and-a-quarter pounds per foot superficial, on the whole surface; the weight of the arched roof of the transept, including the ribs, amounts to five-and-three-quarter pounds per superficial foot; and the timbers and boards of the gallery floor weigh eight-and-a-half pounds to the superficial foot: from these data the actual weight on the different girders may be calculated.
The light iron-work, with the exception of some of the gallery railing, was cast at the works of the contractors near Birmingham; and the remainder, including the columns, girders, &c., was distributed between their own foundry, and those of the Messrs. Cochrane, of Wood Side, and Mr. Jobson, of Holly Hall, both near Dudley. The wrought-iron was supplied by Messrs. Fothergill, and the timber by Messrs. Dowson and Co.
The Parti-coloured Painting.
THE coloured decoration introduced in finishing the painting of the building is a subject which has been much discussed, and many suggestions have been made by persons generally received as authorities on the subject. The system adopted was proposed by Mr. Owen Jones, under whose active superintendence it has been carried out. That gentleman explained his reasons for its adoption, and the effect which he expected it to produce, in a lecture at the Institute of British Architects, on the 16th of December, 1850, some portions of which are submitted to our readers:—
"It is not necessary for me to describe the building, the painting of which we are now about to discuss, as it is well known to most of you by its marvellous dimensions, the simplicity of its construction, and the advantage which has been taken of the power which the repetition of simple forms will give in producing grandeur of effect; and I wish now to show that this grandeur may be still further enhanced by a system of colouring which, by marking distinctly every line in the building, will increase the height, the length, and the bulk.
"The very nature of the material of which this building is mainly constructed, viz., iron, requires that it should be painted. On what principle shall we do this? Should we be justified in adopting a simple tint of white or stone colour, the usual method of painting iron? Now, it must be borne in mind that this building will be covered on the south side, and over the whole of the roof, with canvass, so that there can be but little light and shade. The myriads of similar lines, therefore, of which the building is composed, falling one before the other, would lose all distinctness, and form, in fact, one dull cloud overhanging the Exhibition.
"A line of columns (as it may be seen even now at the building) would present the effect of a white wall, and it would be impossible, in the distance, to distinguish one column from another. This mode of painting would have the further disadvantage of rendering the building totally unconnected with the various objects it is to contain.
"May the building be painted of a dark colour, like the roofs of some of our railway-stations? This, equally with the white method, would present one mass of indistinctness; the relief of the cast-iron would disappear, and each column and girder would present to the eye but a flat silhouette.
"Let us now consider the building as painted with some pale neutral tint, dull green or buff. In doing this we should be perfectly safe, as, provided the colours were not too pale so as to be indistinct, or too dark so as sensibly to affect the eye, we could hardly make a mistake. Yet how tame and monotonous would be the result! It would be necessary that this tint, whichever we might choose, should be of a very subdued neutral character, in order to avoid the difficulty well known to mounters of drawings and painters of picture-galleries, viz., that in proportion as you incline to any particular shade of colour, so in that exact proportion you injure or destroy those objects it is intended to relieve which may have similar colour. To this, then, we should be reduced—a dull monotonous colour without character. How unworthy this would be of the great occasion! How little would it impress the public! How little would it teach the artist! It would be to cut instead of patiently to unravel the knot.
"We are now brought to the consideration of the only other well-defined system which presents itself, namely, parti-colouring. This, I conceive, if successfully worked out, would bring the building and its contents into perfect harmony, and it would fitly carry out one of the objects for which this Exhibition was formed, namely, that of promoting the union of the fine-arts with manufactures. It would be an experiment on an immense scale, which, if successful, would tend to dispel the prejudices of those whose eyes are yet unformed to colour, to develope the imperfect appreciations of others, and to save this country from the reproach which foreign visitors, more educated in this particular than ourselves, would not fail to make were thebuilding otherwise painted; it would everywhere bring out the construction of the building, which, as I said before, would also appear higher, longer, and more solid."
Mr. Jones then adduced the practice of the ancient and mediæval artists, and explained the kind of colours they generally adopted, mentioning that in the best periods of art the primary colours were chiefly or exclusively used.
"In the decoration of the Exhibition building I therefore propose to use the colours blue, red, and yellow, in such relative quantities as to neutralise or destroy each other; thus no one colour will be dominant or fatiguing to the eye, and all the objects exhibited will assist, and be assisted by, the colours of the building itself.
"In house-decoration we occasionally find a run on one colour; thus we have a green room, a pink room, and a red room; but it would obviously be unwise to adopt any one colour for this building, whose contents will be of all imaginable hues from white to black. Discarding, on the other hand, the perfect neutral white as unfit for the occasion, we naturally adopt the colours blue, red, and yellow, in or near the neutral proportions of eight, five, and three; but to avoid any harsh antagonism of the primary colours when in contact, or any undesired complementary secondaries arising from the immediate proximity of the primaries, I propose, in all cases, to interpose a line of white between them, which will soften them and give them their true value.
"As one of the objects of decorating a building is to increase the effect of light and shade, the best means of using blue, red, and yellow is to place blue, which retires, on the concave surfaces; yellow, which advances, on the convex; and red, the colour of the middle distance, on the horizontal planes; and the neutral white on the vertical planes.
"Following out this principle on the building in question, we have red for the under-side of the girders, yellow on the round portions of the columns, and blue in the hollow parts of the capitals.
"Now, it is necessary not only to put the several colours in the right places, but also to use them in their due proportions to each other.
"Mr. Field, in his admirable works on colour, has shown by direct experiment that white light consists of blue, red, and yellow, neutralising each other in the proportions of eight, five, and three. It will readily be seen, that the nearer we can arrive at this state of neutrality the more harmonious and light-giving will a building become; and an examination of the most perfect specimens of harmonious colouring of the ancients will show that this proportion has generally obtained among them; that is to say, broadly, there has been as much blue as the yellow and red put together, the light and the shade balancing each other.
"Of course, we cannot in decorating buildings always command the exact proportions of coloured surface which we require; but the balance ofcolours can always be obtained by a change in the colours themselves. Thus, if the surfaces to be coloured should give too much yellow, we should make the red more crimson and the blue more purple; that is, we should take the yellow out of them. So, if we had too much blue, we should make the yellow more orange, and the red more scarlet.
"A practised eye will as readily do this as a musician can tune a musical instrument; it is here that science abandons the artist, who must trust to his own perceptions, cultivated by renewed trials and repeated failures."
In concluding, Mr. Jones said, with reference to some specimens of the proposed decoration which had been executed, "I would ask you to banish from your minds the glare of light by which this decoration is now seen—to forget the rough foreground, where men are engaged in every variety of occupation for the completion of this great building; and I would ask you to fill it in imagination with the gorgeous products of every clime. I would ask you to picture to yourselves in the foreground the brilliant primaries, blue, red, and yellow—the rich secondaries, purple, amber, and green, moulded in forms of every conceivable diversity; and, lastly, against them the darker tertiaries fading into neutral perspective.
"The conception of such an effect, difficult even to the artist accustomed to abstract his attention from present interruptions and to calculate future harmonies, is impossible to the uninstructed spectator, who, from the experimental decoration of a single column, draws a premature and, necessarily, a fallacious inference as to the collective effect of the whole.
"From my brother architects I hope for a more patient, a more comprehensive, and a fairer appreciation; for myself, I have a confident hope, grounded on the experience of years devoted to this particular branch of art, that the principles and plans I have had the honour to propose to the Royal Commission, for the decoration of this magnificent structure, will be found, when complete, not to disappoint the public expectations, or to prove wholly unworthy of the great occasion."
In this lecture, Mr. Owen Jones asked his hearers, and the public generally, to suspend their final judgment upon his system of colouring until the whole should be completed, and the building filled with the objects to be exhibited, as he considered that many of the objections which were raised to his proposition resulted from a want of consideration of the ultimate effect to be produced by the whole, when completed and occupied; and so far as this effect has been realised, we believe it has inclined the public opinion more in favour of the coloured decoration than originally, when it was undoubtedly very strongly commented upon in various quarters. Without venturing to express any opinion ourselves, we may trust that Mr. Owen Jones's fondest hopes will be fully realised.
View of the Building from the North Bank of the Serpentine.View of the Building from the North Bank of the Serpentine.
View of the Building from the North Bank of the Serpentine.
View of the Building from the North Bank of the Serpentine.
The Water Supply.
THE supply of water necessary both for the protection of this enormous building from fire, and for the use of fountains and machinery to be exhibited, is furnished at a very liberal rate by the Chelsea Waterworks' Company. It is brought into the building by a 9-inch main pipe, at about the centre of its length, branching out into three 6-inch pipes, which extend throughout the whole length of the building. Short pipes branch off from these, terminating in fire-cocks, placed at such distances that a circle of 120-feet radius from any one of them will touch a similar circle described round the adjacent ones; by which means the whole extent of the building may be brought under the action of hose attached to each of the fire-cocks. The water is supplied at a pressure equal to a column of about seventy feet, so as to work the fountains that will be exhibited, and to play efficiently from hose in case of any accident by fire. The quantity which the Company have undertaken to supply is 300,000 gallons a day.
The Stability of the Building.
THE subject of the strength and stability of the building is one on which considerable anxiety has been felt, both by the public at large and by those professional bodies more capable of forming a correct judgment upon it. In the prolonged discussion which followed the reading of Mr. Wyatt's paper at the Institution of Civil Engineers, many points of objection were raised which seemed at first sight of a very serious nature; but, in most cases, the answers that were given to them were perfectly satisfactory. The two greatest difficulties raised were, firstly, the enormous surface presented by the exterior to the pressure of the wind, with apparently but a slight power of resistance; and, secondly, the construction of the galleries, which, it was thought, would not be able to resist the vibratory motion likely to be produced by great numbers of people walking upon them. The results of several calculations were adduced on the occasion alluded to in support of the objections on the first point; but perhaps the best answer that could be given to them was the circumstance mentioned by Mr. Fox—that on the 5th of that month (January) the pressure of the wind, which blew a perfect gale, was not only much above the average, but very nearly reached the greatest amount known within a considerable period in London—about 25lbs. per square foot; and that as the building, although in an incomplete state, had resisted that pressure without receiving any injury, it was fair to conclude that, when finished, it wouldbe able to sustain the greatest force which the wind could be reasonably expected to exert upon it.
The question of the strength of the galleries was one of even greater importance than the other, as, in case of any failure in that part of the building, human life must almost inevitably have been sacrificed to a great extent. It was therefore deemed necessary to ascertain, as far as was practicable, by experiment, that their strength was abundantly sufficient; and in Mr. Wyatt's paper, as printed, the following description of the experiments instituted for this purpose will be found.
Testing the Galleries.
IN the interval between the reading of this paper and its going to press a series of experiments have been tried to ascertain the action of these galleries under the strain of a moving load. A complete bay, twenty-four feet square, was constructed, raised slightly from the ground, consisting of the four cast-iron girders, with the connecting-pieces at the angles, and on this the timbers and boards of the flooring. Rows of planks the full width of the platform led up to it and down from it, so that a body of men as wide as the gallery might be able to march up and down in close rank.
"The area of the platform was first covered over with labourers packed as closely together as possible; but no action of walking, running, or jumping that 300 men could perform did any injury whatever to it, and the greatest deflection of the girders did not exceed a quarter of an inch. Soldiers of the corps of Royal Sappers and Miners were then substituted for the contractors' men; and although the perfect regularity of their step in marking time sharply appeared a remarkably severe test, a minute examination of the construction after the completion of the experiments showed that no damage whatever had been done by their evolutions.
"But as the Commissioners were deeply impressed with the necessity of thoroughly convincing the public, who should visit the Exhibition, that they might feel perfectly secure in every part of the building, it was deemed desirable to apply a still further test to the actual galleries as they stand; as it might perhaps be said that the single bay which had been experimented upon was not similarly circumstanced to those forming parts of the building.
Testing the Gallery Floor.Testing the Gallery Floor.
Testing the Gallery Floor.
Testing the Gallery Floor.
View of the Boiler House.View of the Boiler House.
View of the Boiler House.
View of the Boiler House.
"For this purpose a very ingenious apparatus was devised by the late Mr. Field, President of the Institution of Civil Engineers, for testing the stability of the galleriesin situ, and on being applied over the greater part of the building not a single bolt or girder gave way under its action. This apparatus consisted of eight square wooden frames divided into thirty-six compartments, each just capable of containing and allowing to rotate a 68-pounder shot. The surfaces of the balls placed in each of these compartments came in contact with the gallery floor, the frames themselves being attached to one another and running along the floor by means of castors fixed at the angles; the whole apparatus being drawn along by a number of men. Two hundred and eighty-eight 68-pound shot confined in a limited area were thus set rolling over more than half the extent of the galleries; when, not the slightest mishap having occurred, the experiment was considered decisive, and a persistence in it deemed unnecessary."
The pressure obtained in this experiment amounted to about a hundred pounds per square foot, and it had been ascertained that the greatest pressure caused by packing men together as closely as possible was equal to about ninety-five pounds per square foot; so that the testing force applied was considered amply sufficient, as a considerable portion of the surface of the gallery will be occupied by light articles exhibited in the cases and stalls which are placed along the centre of the gallery, where a great weight would have most effect.
This ingenious method of proving the strength of the galleriesin situ, without endangering those engaged in the experiment, is admirable; and the result of the proof will no doubt allay all fear in the mind of the public as to the safety of this portion of the building.
General Advantages of the Building.
IT is always much easier to point out the defects of any work than its excellences; whilst we may, therefore, safely leave the former, as regards our present subject, to be discovered and enlarged upon by those who may be perhaps more competent than ourselves, we will attempt to point out what we conceive to be some of the advantages obtained in the present building.
One of the principal of these, considering throughout the purpose of the structure, is, perhaps, the uninterrupted view of the interior which the spectator may obtain from any point of the building—a matter of great importance to the general grandeur of its effect. From the galleries more particularly, which will be less obstructed by large objects, the eye of the spectator will be able to range from end to end of the vast edifice; while the transparency of the material used for the roof allows every object to be brilliantly illuminated. The slender lines of the supports, though they serve to sustain a protecting covering, scarcely interrupt the view of the objects protected, and the absence of any fixed divisions or partitions enables all the articles exhibited to be so arranged as to suit the peculiar requirements of each particular class; while the ample space between thesupports has admitted of the formation of large open avenues for the free passage of visitors, who may thus reach as readily the remotest corners of the building as those situated near the entrances; and whenever the visitor may find himself fatigued by the labour of sight-seeing, he will be sure to find himself near one of the numerous exit-doors, whereby he may immediately free himself from the crowd of spectators.
From the simplicity of the details of the construction, and their constant recurrence, it will be seen that so long as the ends of the building were left incomplete, its size could easily be limited or expanded, so as to include that precise amount of space which, up to the last moment when the point could be kept open, appeared most likely to be required. This simplicity of arrangement will also be found very advantageous in case the building is removed after the termination of its present temporary purpose; as the parts may be easily separated without much injury, and as readily re-erected, either as a whole, or even in many separate buildings, having the same arrangement of parts, without the same general form or appearance.
It has been calculated that the passages remaining in the building, after deducting the space appropriated to the objects exhibited, will hold more than 100,000 persons; though it is not to be expected that half that number will be collected there at one time. The ventilation and supply of fresh air for so vast a throng was therefore a matter of the first importance; and the means already described for accomplishing this great object are so ample, that any inconvenience from oppressive heat or foul air can hardly be expected. The canvass with which the roof is covered will not only serve to modify the heat of the sun in the interior, but it is expected that if it be watered by the hose of engines, it may even reduce the temperature within to considerably below that of the external air. From his experience in glass-houses for horticultural purposes, Mr. Paxton speaks confidently on this point.
The arrangement of the construction of the building resting on isolated instead of continuous supports, will enable all traces of it to be readily effaced from the site if it is removed; and, on the other hand, if it remains, it is evidently peculiarly suited to form a vast winter-garden and public promenade.
Conclusion.
BEFORE taking leave of the reader who may have patiently followed us thus far, a few words may be necessary on the general arrangement of the articles to be exhibited in the building whose outline and details we have been endeavouring to trace. The first classification is geographical. All the western half of the building is given to England, and the eastern, which is rather the larger of the two, to foreign countries;the space assigned to each country being distinctly defined, so as to avoid the possibility of any disputes. As far as it was possible, the space for each country is so arranged as to have a frontage towards the main central avenue, and in most cases occupies a strip the whole width of the building; the visitor, therefore, passing up and down the length, will not miss out any country.
In the central avenue, and immediately on either side of it, are placed the most remarkable specimens of objects coming under the class of fine-arts, or otherwise sufficiently remarkable to entitle them to such a prominent place. Behind these, in the side avenues, will be found the various specimens of manufactured articles; and along the outside longitudinal avenues are placed, on the south side, those belonging to the class of raw products (a portion being devoted to agricultural implements), and the projecting portion of the building on the north side forms the hall of machinery, which is separated by a partition of glazed sashes from the rest of the building. Many of the articles will be grouped in courts, an arrangement which the construction particularly leads to; and these will probably form some of the greatest attractions in the Exhibition, each being, as it were, complete in itself, and the inclosures preventing the eye from being distracted by distant objects. To enter further into the detail of this part of the subject would be foreign to the purpose of this work, the building itself being our text.
We have now, we believe, completed the pleasant task we proposed to ourselves at the outset, and we hope that in doing so we may have been able to render interesting to our general readers this description of operations, usually occupying the attention of the technical professions only. With this intention, we have avoided as far as possible the use of technical terms, which would be a dead letter to the uninitiated, at the risk, perhaps, of being considered inaccurate by those acquainted with all the details of the subject.
So many men whose eminent talent is well known and appreciated by the public have been engaged in perfecting the designs and carrying out the erection of this vast structure, that the critic should be one of no mean reputation who would venture to raise even a small voice of individual criticism on its merits. We have considered it, therefore, to be our part rather to record the opinions of others on any points where a discussion has been raised than to trouble the reader with any personal views, which would, perhaps, have only appeared impertinent.
The nature and extent of the difficulties which have been successfully surmounted in carrying out this great work can only be fully appreciated by those intimately acquainted with all its structural details and with its rapid progress; and its completion in so short a period must be regarded as a striking instance of the productive power and spirit of commercialenterprise of this country, while the fact of its being defrayed by the voluntary contributions of the people will illustrate in an interesting manner to our continental visitors that principle of self-government which forms the basis of all our institutions, and the spirit of private enterprise which characterises most of our great undertakings.
The illustrative engravings with which we have endeavoured to render more interesting the descriptive details, necessarily somewhat dry to the general reader, are only intended to convey general ideas, without attempting that minute accuracy which would be required in a more technical work; and with reference to some of them we take this opportunity of acknowledging the assistance our artists have derived from views already published elsewhere, others having been exclusively drawn for the present work.
We have much pleasure in presenting our readers, in the Appendix, with views and descriptions of two of the most striking designs sent in the first competition for the building, the materials for which have been kindly afforded us by their respective authors; and we may remind the reader that these two designs were specially mentioned by the Building Committee in their Report already quoted. In the same place some interesting documents connected with the building will also be found, which we were unable to insert in the text.