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galleries. The railing of the staircase is formed in separate cast-iron standards, one to each step, bolted on to the top flange of the girders, and the foot of the standard is continued so that the ends of the treads fit into it, and are thus supported.

The hand-rail for the galleries and staircases is of Honduras mahogany, and in order to produce it with rapidity it was turned out by machinery. The mahogany was supplied in slabs of the proper thickness, and these were cut up with circular saws into lengths of a square section: the angles were then bevelled

off, and the rough length of mahogany was rounded, at the hand-rail cutting machine. This consists essentially of a hollow cast-iron cylinder driven by a strap passing round it. Four cutters are fixed at one end of this cylinder, as shown in Fig. XXXI., so that a piece of wood passing between them and through the cylinder, as it revolves, is rounded off cleanly and smoothly, requiring only a little sand-paper and French polish to finish it. The wooden rail is passed up to the cutters along a groove, and opposite each end of the revolving cylinder springs are fixed, which prevent the rail from shifting its position. In advance of the cutters are pressure-rollers furnished with teeth, and these by their revolution seize upon a piece of mahogany, and force it forwards against the cutters. About thirty lengths of hand-rail, each 24 feet, were thus completed in a day.

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Fig. XXXI. HAND-HAIL CUTTING MACHINE.

We come now to notice the construction of one of the most distinctive features of this extraordinary building, viz. the glass roof. The several parts of which it consists will require to be considered at some length; but by referring to Fig. XIX., which represents one of the 24-feet bays, and to the various other figures and descriptions of the different parts, a clear idea of this ingenious structure may be gained. This figure also shows the position of the gutters, the principal rafters or main sash-bars, and the ridge. These being fixed in place, the long edge of a sheet of glass is inserted into the groove of the principal rafter, and a doublegrooved sash-bar is then put on to the other long edge of the glass: the sash-bar is next brought down and secured at the top of the ridge and at the bottom to the edge of the gutter, the lower edge of the glass bedding on putty. A slight blow applied to the lower end brings the upper edge of the glass home into the groove in the ridge. The glass is then pressed down, the putty made good in the grooves externally, and the operation is completed. A roof thus formed weighs only 31 lbs. per foot superficial, on the average, the weight of the trusses that support it being deducted. To mitigate the intensity of the light, this roof is provided with a canvas cover attached to the ridges, and hanging down between them in a festoon. For this purpose two widths of canvas are sewn together, the seam being in the centre immediately over the Paxton gutter. The rain which falls on the canvas creeps down it until it reaches the seam, when it passes through, and falls into the gutter: by this contrivance the leakage of water through broken panes and imperfect putty joints is avoided.

The Paxton gutters or rafters which span the space between the girders, were formed with great rapidity by very effective machinery arranged by Mr. C. Cowper. The pieces of timber intended to form the gutters were sawn into lengths of 24 feet, 6 inches deep, and 5 inches thick. They were then planed on the four sides at Furness's planing machine. In this machine, cutters attached to the ends of an arm revolve with great rapidity in a horizontal plane three widths of timber are wedged up in a frame traversing on rails, and as this is passed under the revolving cutters, the upper surface is planed off, the timbers being held down upon the frame by a large iron disc.

On leaving the planing machine these quarter baulks were passed on to the gutter-cutting machine, the details of which are given in the following figures. Fig. XXXIII. is a side view

of a cast-iron block, to which steel cutters, cc, are attached by bolts and nuts, B B. Four such blocks required to form the gutter, are fixed to four spindles, and by the action of drums upon

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them are set in rapid motion by bands. A piece of timber exposed to the action of these cutters must evidently be scooped out into the form of the outline of the cutters attached to each block, and by varying the form of the cutters any variety of section can be given to the timbers. In the present case the first set of cutters roughly hollowed out the larger groove, as in Section 1, Fig. XXXIII.; the two next sets of cutters were counterparts, and formed the same section in opposite directions; these cutters being set at an inclination to the upright of about 45°, one to the right and the other to the left, each hollowed out one of the small side grooves, and one side of the larger gutter, leaving the section as in 2 and 3. No. 4 is the section

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Fig. XXXIII.

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Fig. XXXIV.

after passing through both. The action of the machine will be seen by referring to Figs. XXXII. and XXXV. The piece of timber is

placed upon the roller E, and pushed on until it comes in contact with the roller F, furnished with projecting points, which seize it and propel it forward, so as to bring it under the action of the set of cutters marked A: then passing onwards to B it is operated on by a second

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Fig. XXXV. SECTION OF GUTTER-CUTTING MACHINE.

set; at c by a third set; and in passing through D, the gutter is completed. The section, Fig. XXXV., shows the angles at which the cast-iron blocks holding the cut. ters revolve. G is the gutter kept in its place by the holdfast H. By this machine 3 feet of gutter can be made per minute; the 110,000 feet, or nearly 20 miles, of gutter required for the building were completed in two months.

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As the gutters were delivered at the works they were carefully examined, and the defective ones rejected; they were then cut to the exact length so as to fit in their places. For this purpose each gutter was fixed in a framework and bent to the same curve which it would have when fixed, a necessary precaution, in order to cut off the ends vertically. At one end of this framework a circular saw 20 inches in diameter was hung with a pulley and balance weight, so as to be capable of being moved up and down by a lever. The gutter was fixed in its frame by hinged gauge-plates, and the end was cut by bringing down the circular saw. Another operation was also performed at the same time. In the centre of the circular saw two cutters were so arranged that when brought down upon the end of the gutter they cut out a semicircular notch, so that when the

ends of two gutters were placed together, a circular hole was left for the passage of the water into the main gutter. When one end of the gutter was thus operated on, the gauge-plate was taken off, the timber swung round on a pivot or crutch in the centre, and the process repeated, the whole operation occupying about 2 minutes.

The solid gutter was then taken by the carpenter, who fixed at each end on the under side a small cast-iron shoe, and two struts 9 inches long, so as to divide the length into 3 equal parts; the struts were spread out at top so as to present a large surface of pressure against the under side of the gutter, and tenons projecting upwards fitted into mortices cut in the timber. The lower ends of the struts were so formed as to give them a firm hold upon a wrought-iron rod 18 inch in diameter, which was passed under them and through the shoes, where it was screwed up with nuts, and the struts pressing upwards against the timber gave the gutter a camber or rise in its whole length of 21

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inches: 27 notches for the reception of the sash-bars were then marked with a template, and cut out on each edge of the upper side of the gutter. A small cast

Fig. XXXVI.

iron plate was next fitted on the under side at each end, and the gutter was then complete and ready for fixing. The under trussing of these gutters or rafters increased their strength considerably, so that a weight of 14 ton was required to break one.

Fig. XXXVII.

The Paxton gutters follow the direction of the length of the building: at right angles to these, and supported by the roof girders, are the box gutters c, Fig. XXXVIII., which receive the drainage-water collected by the Paxton gutters, and discharge it down. the hollow columns into the drains.

We come next to speak of the sash-bars. When it is considered that about 200 miles of sash-bars were required for the roof, it may readily be supposed that self-acting machinery was alone adequate to their production. Indeed, if the contractors had had to rely only on the productive powers of workmen, however skilful and industrious, the Palace of Glass could not have been produced; but when such powerful machines as those which we have described work with untiring energy night and day, and supply the place of thousands of mechanics, great and useful undertakings which would otherwise be impracticable, are not only rendered possible but comparatively easy. It is also interesting to remark that such machines which seem to demolish labour, actually increase it to an incalculable extent; 2,000 men were employed at good wages within the building for some months, and many thousand men were working night and day for the same or a longer period in preparing the iron, the glass, the timber, &c., to say nothing of the vast impulse given to the industry of the whole world by this truly great Exhibition.

The machine for shaping the sashbars was a modification by Mr. Birch of Mr. Paxton's machine, already noticed at page xxi. In Mr. Birch's machine revolving cutters are substituted for saws, thus getting over any difficulties respecting the grain

of the wood; and by the

addition of a second set of Fig. XXXIX.

Fig. XL.

SASH-BAR MACHINE.

B

B

Fig. XXXVIII.

cutters, a plank passed between them is worked upon its upper and under surfaces at the same

time.

A cast-iron block with cutters attached to it, Fig. XXXIX., is moved upon an axis ▲, Fig. XL. As soon as the plank presented by the feed-rollers has been operated on by

Fig. XLI.

Fig. XLII.

Fig. XLIII.

Fig. XLIV.

these cutters, it is carried on by the roller c, and subjected to the action of circular saws of varying diameters, the smaller of which cut just deep enough to form the groove for the glass, while the larger pass completely through the plank, and divide it into four finished sash-bars. The sections, Figs. XLI. and XLII., show the sash-bars for the vertical lights; the shaded part being that which is removed by the machine. Figs. XLIII. and XLIV. show the method of cutting the sash-bars for the roof. These variations in form are produced by varying the cutters attached to the block, Fig. XXXIX.

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The sash-bars were finished at the building, and made to fit the notches prepared in the ridges and gutters, Figs. XIX. and XXXVI. Thirty bars were first placed together in a horizontal traversing frame, on a saw-table, on each side of which were circular saws, fixed at a distance from each other equal to the required length of the sash-bars; the frame was then moved forward against the saws, and both ends of the whole set were thus cut off; at the same time, a cut was made at one end half-way through the bar, in order to form a shoulder against the gutter. The bars were then removed to another bench, where the bar was bevelled and the shoulder formed by means of a small instrument, consisting of a handle with two projecting jaws fitting into the ends of the glass grooves of the bars: between these was a small blade, which being pressed down, cut out the shoulder which had been sawn through in the other direction, and another blade was placed at the proper angle to remove the bevelled piece at the end of the bar. A hole was next drilled at each end for the purpose of nailing the bars down on the gutter and ridge; and to ensure the holes being all drilled at the same angle, the following method was adopted :— side of the horizontal bench was a set of 4-inch driving pulleys, furnished with horizontal drills projecting to the other side of the bench; a wooden traversing plate, placed opposite each drill, and working towards it, received one end of the sash-bar, while the other rested in an inclined position against a wooden rail placed above the pulleys, and furnished with as many sinkings therein as there were drills. The traversing plate pushed forward the sash-bar to be perforated by the drill; the plate was then drawn back, and the same operation repeated with the other end of the bar, which was then ready for fixing. The ordinary sash-bar is shown in Section Fig. XLVI. One out of every nine of the sash-bars was made stouter than the rest, for the purpose of fixing the ridge preFig. XLVI. vious to glazing. This stouter bar, shown in section Fig. XLV., 2 inches by 14 inch, is grooved for glass on both sides, and notched down: being set at a pitch of 21 to 1, and fixed to a ridge 3 inches by 3 inches, also grooved for glass on both sides. After the ridges were cut to the exact length, two holes were drilled at each end to receive the dowells for connecting it with the adjoining length.

Fig. XLV.

In painting the sash-bars, labour was greatly abridged by mechanical contrivance. A number of brushes were arranged in a frame at right angles to each other, in such a manner that their bristles would just allow a sash-bar to pass. A number of sash-bars were immersed in a trough full of colour, and one of them being lifted from it loaded with colour, and presented to an opening at one end of the series of brushes, was passed through them, and the superfluous paint removed, when the bar appeared at the other side neatly painted.

In putting together the sash-frames and sash-bars, Furness's machine for making mortises and tenons was found of great use.

While all these arrangements were being carried out according to a well-ordered system, it was highly interesting to pay a visit to the works, which the writer had frequent opportunities of doing. Although upwards of 2,000 workmen were employed, they, as well as the visitors, seemed lost by being distributed over the vast area. During the early proceedings, the most

remarkable characteristic was the absence of noise, calling to mind the building of the Temple, where "there was neither hammer nor axe, nor any tool of iron heard in the house while it was in building;" but as the building began to grow, the sound of tools and machines in motion was heard in the immediate vicinity of the spots where they were used. "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 100 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, 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 unwieldylooking girders to their places; while other teams were engaged in running them up to their final position. Overhead, too, the glaziers' wagons, dotted about the roof, seemed to be running on some new aërial railways: in every direction that the eye turned, the busy scene extended. For carrying on these extensive works, an immense number of men was 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 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."'

We have thus traced the erection of the building up to the level of the roof of the nave and side aisles. Arrangements for the glazing of these portions of the building were skilfully made so as to shelter the workmen from the weather. For this purpose a travelling stage was invented by Mr. Fox: it was about 8 feet square, and rested on four small wheels travelling in the Paxton gutters. It thus spanned a width of one bay of 8 feet of the roof, including one ridge and two sloping sides. By means of 76 of these stages or glazing-wagons, the whole of the flat portion of the roof was glazed. Each stage was occupied by two men, and was covered by an awning of canvass, stretched over hoops, to protect them from the weather: it was also provided with a box

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Fig. XLVII. GLAZING WAGON

on each side for containing a supply of glass. The sash-bars and other materials were piled upon the stage; and in the centre of the stage was an opening sufficiently large to admit boxes of glass, supplies of sash-bars, putty, &c. being hoisted up from below by means of a pulley attached to an iron arm.

The ridge having been previously fixed in position by means of the extra strong sash-bars, the men, sitting at one end of the platform, fixed the glass in front of them, pushing the stage. backwards as they completed each pane. On coming to the strong sash-bars previously fixed, they removed them in order to allow the wagon to pass. In this way each wagon travelled from the transept to each extremity of the building. One man could, on an average, glaze 200

(1) "The Crystal Palace; its Architectural History and Constructive Marvels. By Peter Berlyn and Charles Fowler, jun." In the preparation of this Section, we have to acknowledge our obligations to this work, as also to the Illustrated London News, and to Mr. Digby Wyatt's paper on "The Construction of the Building," contributed to the Official Descriptive and Illustrated Catalogue. (2) Fig. XLVII. will give some idea of this contrivance, although, from a mistake of our artist, the glazier appears to be working with an opaque instead of a transparent material.

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