contractors on the 30th July; the first column was fixed on the 26th September. As the design was novel, so the appliances for carrying it out presented much of originality-even the first step, that of inclosing the ground, was new and ingenious: a double row of uprights, being the same timbers which were afterwards to be used as joists, were driven into the ground at suitable intervals; boards, which were to form the future flooring, were dropped into the interstices, and held in their places by iron rings dropped over the head of each pair of uprights-thus not a single nail was used in the whole enclosure, not an inch of plank was injured or wasted, and the whole underwent an admirable seasoning. The ground was next traced out, the exact position of each column being ascertained by the theodolite, and concrete foundations formed. The chief materials of the structure, the iron columns and girders, now began to pour in. As every casting was delivered on the ground, it underwent a careful examination, and was immediately painted. The girders, upon the perfect soundness of which the stability of the galleries and roof mainly depended, were subjected to a rigorous test, in a machine arranged for the purpose. One of Mr. Henderson's patent cranes was so placed, that, on a waggon containing girders being brought beneath its range, a girder was lifted from the waggon and deposited upon a weighing apparatus. An account having been taken of its weight, the girder was again lifted by the crane, and carried forward to an extremely strong frame, the two ends of which corresponded in form and dimensions to the con necting pieces with their projections. The girder being securely confined in these clutches, a force was exerted upon it at the two points upon which the weight of the floors and roofing would have to be carried, that is to say, immediately over its vertical lines. The force thus communicated was applied by two pistons, forced upwards by a modification of the hydraulic press. A registering apparatus affixed to the pipe leading from the force-pump to the testing-machine, afforded the means of adjusting the pressure exercised by the hydraulic press. A careful observation of this apparatus conveyed the assurance, that every girder, according to its ultimate destination, was proved to a strain of either 9, 15, or 22 tons. testing, the girder was released from its confinement, again raised by the crane, and stacked in a convenient place ready for removal. So admirably were the various arrangements made for conducting these operations, that it was possible for a girder to be lifted from its waggon, weighed, secured in the testing-machine, proved, released, again raised, and finally deposited in less than four minutes. After In order to elevate the columns to their places, what is known in technical language as a pair of shear-legs, was employed. This simple apparatus consists of two poles lashed together at their heads, and maintained in a steady position by ropes extending from the apex of the triangle formed by the base-line of the ground and the inclination of the poles to one another, to stakes driven into the ground at a considerable distance. From the apex of the triangle a series of ropes passing over pulleys were suspended perpendicularly; and, by means of this "fall," the majority of the columns, girders, and other heavy portions of the construction, were elevated to their places. Modifications of the simple apparatus described sufficed to hoist almost every part of the necessary ironwork. A connectingpiece was attached to each column previous to its elevation; and so soon as two columns with their connecting pieces were fixed, a girder was run up, slipped between the projections of the connecting pieces, and secured in its place. An opposite pair of columns having been similarly elevated, another girder was attached to them; and thus two sides of a square were formed, and maintained in a vertical position by poles acting as supports to them. Two other girders being then hoisted, and slipped between the connecting pieces on the remaining two sides of the squares, a perfect table was constructed. The "shores" or supports were then removed, together with the shearlegs, and the whole apparatus was at liberty, for the purpose of recommencing a similar operation in an adjoining 24-feet bay. When a sufficient number of these bays had been completed (starting from the intersection of the Nave and Transept) to warrant the addition, the hoisting of the columns for the first floor was commenced; more lofty shear-legs being of course employed. The extension of the ground-floor structure proceeding, as that of the first floor was carried on, a base was in turn afforded for the columns of the third tier; and thus the iron framework of the whole building rose from the ground, firm and secure, without involving the ne cessity of any scaffolding what ever. While these operations of actual structure were being carried on, the work of preparation was yet more vigorously pushed. The Paxton gutters and sash-bars, prepared by ingenious machinery, were got ready by mile lengths. The latter were even painted by mechanical assistance. While the various machines were busily operating in the preparation of the necessary framework to receive the glass, the makers of the glass were not less actively employed. The large size of the sheets required (4 feet 1 inch by 10 inches), and the short time within which the immense quantity necessary had to be supplied, demanded the employment of numerous additional hands, and workmen had to be sought for from abroad to assist in the completion of the order within the requisite time. The mode of manufacturing the description of glass employed is a great improvement on the old system of crown-glass making, as by it the variation of the substance occasioned by the thickness of the glass, as it approaches the bull's-eye, is completely avoided. In the manufacture of sheet glass, the workman, having taken up a lump of glass on the end of his pipe, alternately blows, swings his ball of glass to and fro, and rolls it upon a metal table until it assumes the form of a long cylinder; the ends being then taken off, and the cylinder cut in the direction of its length, the sheet of glass falls down, is flattened to a perfectly true face, and is then trimmed off and finished. During the preparation of the materials necessary to commence the construction of the Paxton roofing, active progress had been made in the framing of the wroughtiron trusses requisite to span the central 72-feet nave, and the 48feet avenues on each side of it. A steam-engine of 6-horse power gave motion to drilling, punching, and cutting-machines. By means of these, the necessary pieces of bar-iron were adjusted to their requisite lengths. While these active preparations for the construction of the roofing were in progress, the daily supplies of castings of every description were of the most abundant nature; no less than 316 girders having been cast and supplied in one week. As fast as the columns came upon the ground, they were taken to their places and immediately fixed. Up to the 20th of September, 77 columns had been supplied. By the week ending the 25th of October, the average number fixed per week amounted to nearly 200, and that rate of supply was continued for several subsequent weeks. The attention of the contractors was next directed to the formation of the transept ribs. The choicest timber was selected for that purpose their form was set out upon a platform erected for the purpose, and the timbers for the first rib laid down. When the rib thus commenced was completed, it was made to serve as a template for the construction of a second; and thus one was fitted upon the others, until the pile had accumulated to four. Three of these having been then laid down in other places, the remainder were constructed upon them in a similar manner. As supplies of the smaller castings necessary to complete the various portions of the structure poured in, the work of erection and putting together proceeded with wonderful rapidity. Towards the beginning of December, the climax of activity was arrived at, and the most trying operation in the whole construction of the building commenced, namely, the hoisting of the main ribs for the great transept-roof. The raising of the main ribs commenced on the 4th of December, and the whole sixteen were fixed in one week. It occupied about an hour to raise a pair of ribs from the ground to the level of the lead flat, but the previous preparations involved a much longer space of time. Eleven men worked at each crab, and about sixteen were employed on the lead flat, to guide the ribs in their ascent, and see to the safe condition of the shearlegs and tackle. Considering the anxious nature of this performance, it must be regarded as a most gratifying circumstance, that the whole operation was accomplished without any untoward occurrence. No sooner had the skeleton of the transept-roof been completed than the work of glazing the whole roof commenced. And in this, ingenious machines were employed; one variety of these was capable of accommodating two glaziers ; these machines consisted of a stage of deal, about 8 feet square, with an opening in its centre sufficently large to admit of boxes of glass, and supplies of sash-bars, putty, &c., being hoisted through it. The stage rested on four small wheels, travelling in the Paxton gutters. The dexterity acquired by the men in working the machines was very remarkable. By means of them, 80 men in one week put in upwards of 18,000 panes of glass, being not less than 62,600 feet superficial. The greatest number of panes inserted by a man in one day was 108, being 367 feet 6 inches of glazing." It is gratifying to be able to state that Messrs. Fox, Henderson and Co.'s astonishing contract to deliver over the building-or "the Crystal Palace," as it was now generally denominated, on account of the fairy-like beauty of the structure-to the Commissioners, on the 31st December, was punctually performed-the crystal edifice had sprung out of the ground almost with the silence and rapidity of Aladdin's Palace; and although the severity of the frost had put a stop to the operations of the glaziers, yet three-fourths, and by far the most important portion, had been covered in; and punctually on the 1st of January the Commissioners occupied the vast space with their carpenters, painters, and artizans, and urged forward the final preparation for the reception in the world's wonder in architecture of the world's wonders of art. Among the later operations connected with the completion of the work, the most remarkable for the celerity with which it was conducted, was the ornamental painting of the nave roof. Iron straps, attached to the trusses, supported a number of scaffold poles, on which a perfect cloud of boards was laid, and as many as between 400 and 500 painters, by these means, worked their way, with extreme rapidity, from one end of the building to the other. By the 1st of May the building was completed; the interior and a great part of the exterior were painted; the roof covered with canvas, and the crowds of workmen of all kinds, exhibitors, and their assistants, were replaced by the vast assembly collected to witness the inauguration of the Exhibition by Her Majesty, which took place punctually on that day, as determined sixteen mouths before. 472 PATENTS From January 5th to December 28th, 1850. It is frequently difficult to make an abstract of the lengthy descriptions given by the patentees of their inventions, sufficiently short for the purpose of this list, and yet sufficiently accurate to indicate exactly the nature of the invention. It is hoped, however, that sufficient is given to afford to an inquirer the means of making more accurate researches in the official records. Ackroyd, dressing fabrics, June 19 Ashworth, spinning and weaving, May 29 Auchterlonie, ornamental fabrics, Feb. 7 Baranowski, counting, April 23 Barber, desk seals, Nov. 30 Barbor, artificial fuel, Jan. 17 Barclay, rotary engines & fans, Sept. 5 Bell, waterclosets and air-traps, July 25 Bernard, meumatic springs, Oct. 3 Brooman, abdominal supporters, July 31 Brooman, purifying water, Sept. 19 Brooman, types, March 7 Brooman, zinc, April 20 Brown, fluid meters, June 1 Brown, lift and force pumps, Nov. 19 |