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of the carpet-is precisely similar. In fact, Axminster no longer produces carpets, the business there being utterly extinct. Tapestry carpets are those produced by the needle; they are, in fact, needle-work carpets, in which machinery has very limited duties to perform, and those of a simple character. Tournay and Axminster carpets are produced by hand also; a machine, if such it may be called, which is nothing more than a frame, such as ladies use for stretching their canvas for needle work, is set up perpendicularly, and the woman occupied in the production is seated in front, and works horizontally. Each thread is knotted to the foundation or back, and is not in any other way connected with any other thread. Velvet pile, royal pile, and Saxony carpets are all the same kind; the names being given at the caprice of the manufacturer, and conveying no definite idea of the quality. They are each and all manufactured in the same loom; are all, in different degrees, the same fabric, and often the same pattern, as Brussels carpet. In fact, the worsted loops is the distinguishing characteristic of the Brussels carpet. When cut open by a razor, the tool used by the weaver for the purpose, passing across the carpet, and guided in its course by a grooved wire, over which the loops have been formed, it becomes a "Saxony;" a wire of larger dimensions produces a larger loop, and this, laid open by the same primitive process, produces a "velvet pile."
Here, again, we may notice that names are capricious. Brussels sup. plies but few of the carpets that bear the name, and Kidderminster manu. factures altogether a different article from those which it gives appellation to in the market.
No single article in the way of carpeting-in fact, perhaps no single article of any kind-attracted more attention throughout the time of the Exhibition than the tapestry carpet from the Gobelins. The date of this world-renowned national establishment of France is very remote. From the 14th century dyers in wool have been established in the Faubourg St. Marcel. One of them, Jean Gobelin, who lived in 1450, acquired considerable property in the neighborhood. His descendants continued his trade with success, and, having become extremely rich, gave great renown to their manufactures. Louis XIV purchased the premises and erected there a national manufactory. From that day, what of genius, taste, science, and wealth could be devoted by the patronage of the French government to the production of Gobelin's tapestries, has been done. In the tapestry work, the workman stands at the back of the canvas on which he is employed, with the model behind him, to which he occasionally refers, in order to adjust the color of his woollen or silken thread to that part of the picture he is copying. The object of the process being to present as smooth and delicate a surface as possible, all cuttings and fastenings are performed at the back. Hence the neces sity of his working on the wrong side. Some of these carpets take as long as ten years to finish, and cost 150,000 francs. They are never sold. The closeness with which the painter's art is imitated is wonder. ful. In the battle scene represented in the large piece sent to the Exhibition, it was impossible to detect a shade of difference from the real picture the drawings, the colors, the perspective, all being precisely similar to the model.
In the patented processes by which English carpets are just now be ing made, there is much that looks like an entire revolution in the old
way of manufacture. To understand the results, the means by which they are arrived at being kept secret, it is necessary to go back to the first improvement in the manufacture of Brussels carpets, patented by Mr. Whytock. In the old method of this manufacture, about two-fifths of the worsted is used in the back of the carpet, and seven colors are the greatest number which can be introduced by the weaver; in consequence, the carpet is more costly than is necessary for wear, good material being consumed in a part never used; and the designer finds himself shackled by the limits to his coloring. By Mr. Whytock's invention, each indi vidual thread is dyed with all the requisite colors of the carpet, and in the precise quantities required for its position in the pattern. The ob jection to this improvement was, that while it gave no limits to the colors required, it demanded a nicety of calculation that subjected the whole product to the risk of ruin upon a single mistake in the weaver: neither did it affect the price of the kind of carpets to which it was ap plied, since all that was gained in the saving of worsted from the back was lost in the enhanced difficulty of the manufacture.
Another patent was obtained, and is worked by Messrs. Templeton & Co., of Glasgow. It is used only for producing carpets of a superior quality, which are expected to find consumers among those who would otherwise be purchasers of tapestry or Axminster. It is sufficient for our present purpose to say that by this patent chenille is dyed and woven in pattern as worsted is dyed and woven by Whytock's patent. In the method of working, some differences exist between the two, but the general result is the same.
But the patent which we have now reached, and to which we beg to call the attention of our carpet manufacturers, is that of Messrs. Bright & Co. By this process the carpet is woven, without colors, simply in white worsted, by the ordinary power looms. The wires used in the ordinary process are entirely dispensed with, and the loop is formed by an arrangement in the machinery. The pattern is then printed on the carpet by a process that strikes the colors quite through the fabric, and, at the same time, prevents the possibility of their running into and mixing with each other; thus a Brussels carpet is produced by a simple mode of operation, and by machinery that is admirably and ingeniously adapted for the purpose. By this process an immense saving in cost must be effected, while the designer is left free to indulge his taste or fancy to the utmost. Instead of the razor, heretofore used to cut the threads in producing the "velvet pile" carpets, the whole process is accomplished by mechanism. While the process of weaving is going on in the loom, an instrument is put in motion that cuts the loop with per fect accuracy. The process is far from what it may become, but it suggests an idea in the manufacture of carpetings which will certainly be shortly realized.
Towards the close of the Exhibition, Mr. Bigelow, of Boston, exhibited several specimens of Brussels carpetings woven by the power-loom, which excited much attention. This process, invented and patented by Mr. Bigelow, and now in general use in the United States, is altogether unknown here, the owner of the English patent objecting to its use here, as likely to be detrimental to the business at home. It is, perhaps, one of the greatest improvements yet made in weaving, and accomplishes what has heretofore been deemed an impossibility, viz: the use of all varieties of colors in the power-loom.
There was no department in the Exhibition which presented to the spectator so much to attract his observation and occupy his thoughts as that of machinery.
The great influence which machinery is destined to exercise over the fortunes of mankind can scarcely yet be understood even by the most enlightened; for there is no limit to its power, no boundary to its application. Here it is that we discover how mechanism is extending her dominion over the whole empire of labor; how she rises in textile fabrics to the manufacture of the most delicate and intricate lace; how, from wood, she aspires to fashion iron in'o the most exact proportions; how, with steam as her handmaid, she works the printing press and navigates the ocean, and outruns the swiftest animal in her course. Turn into the agricultural implement department, and we find everything now done by machinery. By it the farmer not only sows and reaps, but he manures and hoes; by it he threshes out and grinds his corn and prepares the food for his cattle. He can even drain by machinery, and it is difficult now to find a branch of his business into which it does not largely
The space allotted to machinery was divided into six classes, commencing with
CLASS 1.-Machines for direct use, including Carriages, Railway, and Marine Mechanism.
In this class the number and interest of the objects displayed were very great; more particularly as regards the steam engines, of which the show was on a scale commensurate with their importance, many exhib iting admirable specimens of workmanship and new adaptations of mechanism to increase the power of the engines and to add to their safety.
The "Liverpool," locomotive engine; built by Messrs. Curtis, Burry, & Kennedy for the London and Northwestern Railway.
This gigantic machine is constructed on the principle of the Crampton patent, the peculiarity of which is that the driving wheels are placed at the rear of the engine, immediately under the fire box.
It was built when the "battle of the gauge was raging at its fiercest," and when it was one of the favorite boasts of the broad gauge champions that an engine equal in force with the largest in use on their gauge could not be made to run on a 4-feet 81-inch gauge. Το prove the contrary of this was the object of the "Liverpool."
This great machine is supported on eight wheels, the driving wheels being eight feet, and the supported wheels four feet, in diameter. The cylinders are eighteen inches diameter, and twenty four inches stroke.
The evaporating power of the boiler must be enormous, since the heating surface exposed to the direct action of the fire is 156 square feet, and the total surface of the tubes which traverse longitudinally the boiler, and by which the gaseous products of combustion are conducted from the fire-box to the chimney, and strained of their heat en route, is not less than 2,090 square feet.
It contains, therefore, 2,090 feet of heating surface, being 270 feet more than the largest engine on the broad gauge. The weight of the engine, when supplied with its full complement of coke and water, is 37 tons. Its length is 32 feet. It is stated to have attained a speed of 100 miles an hour with a train of 39 loaded carriages.
The "Lord of the Isle."-Sent by the Great Western Railway Company.
This is one of the ordinary class of engines constructed by the above company since 1847. It is one of the largest yet built by them for their broad gauge line. It is capable of taking a passenger train of 120 tons at an average speed of sixty miles an hour upon easy gradients. The evaporation of the boiler, when in full work, is equal to 1,000-horse power, of 33,000 pounds per horse; the effective power, as measured by a dynamometer, is equal to 743-horse power. The weight of the engine in working order is 35 tons, which does not include the tender, which, under similar circumstances, weighs 17 tons 13 cwt. The diameter of cylinder is 18 inches; length of stroke, 24 inches; diameter of driving wheel, 8 feet; and the maximum pressure of steam, 120 pounds on the square inch. The actual consumption of fuel in practice, with an average load of 90 tons, and an average speed of 29 miles, including stoppages, (ordinary mail train,) has averaged 20.8 pounds of coke per mile. The tender is capable of containing 1,000 gallons of water and 1 ton of coke.
Ariel's Girdle.-A locomotive, invented by Mr. Adams, of Adam St., Adelphi, London.
This engine is on four wheels, and contains its supply of water and coke without requiring a tender. It is called a tank engine, and exhib. its several improvements, the chief of which consists in its mode of connexion with the passenger carriages. Long iron arms project beyond the buffers, and are inserted into the frame work of the adjoining carriages in such a manner as to give mutual support should the axles of either the engine or of the carriage break.
This engine may be readily detached from the carriages by means of a handle at the back, within reach of the engineer. The weight of this combined engine and tender, capable of containing a supply of water and coke to serve for 50 miles, is only eight tons. It is calculated to propel three loaded carriages at the ordinary speed.
A light Locomotive.-By Messrs. Wilson & Co., Westminster.
The peculiarity of this engine consists in its having two boilers heated by the same furnace, by which arrangement a larger heating surface is obtained, with the important advantage of lowering the centre of gravity, thereby increasing the steadiness of motion and diminishing the risk of running off the rails. This is also a tank engine, and will carry 520 gallons of water, its weight 16 tons, and 40-horse power.
Hydraulic Press.-The Bank Quay Foundry Company, Warrington.
This hydraulic machine is the one by which the memorable engineering power of raising the tubes of the Britannia bridge from the level of
the water to their permanent position-a height of 120 feet-was executed, and cannot fail to attract the attention of all who are capable of appreciating the wondrous expedients supplied by science to art.
Let us imagine two strong cylinders of cast iron, one of a large the other of small capacity, having a pipe of communication between them, in which a valve is placed opening from the small towards the larger cylinder.
At the top of each of these cylinders is a water-tight collar, in which is inserted a cylindrical rod, turned exactly to fit the collar, and which, moving in the collar so as to be water-tight, descends into the cylinder. These rods are each a little less in diameter and in length than the cylinders, so that, when they have descended in them, a space will remain around and below them. The larger of these rods, which moves in the great cylinder, is called the "ram," and the smaller, which moves in the lesser cylinder, is called the "plunger."
We will then suppose that the ram is let down in the great cylinder, and the plunger raised to the top of the small cylinder, and let the two cylinders and the communicating pipe be imagined to be completely filled with water.
If the plunger be then pressed down in the small cylinder, it will drive so much water as it displaces from that cylinder through the communicating pipe and valve into the large cylinder, where the ram will be compelled to rise to give space for it. The height through which the ram will be thus raised will depend on the proportion which its magnitude bears to that of the plunger; thus if the bulk of an inch of the ram be 500 times greater than the bulk of an inch of the plunger, it is evident that the 500th parth of an inch of the ram will occupy a space equal to and will displace as much water as would an inch of the plunger. To raise the ram, therefore, in such case through the height of one foot, the plunger should be moved through 500 feet.
Each time that the plunger is raised to repeat the stroke, water is drawn in the lesser cylinder, so as to refill it from a reservoir, on the principle of the common pump; and during this process the water which had been driven into the large cylinder cannot return, being stopped by the valve of the communicating pipe, which only opens towards the larger cylinder.
To estimate the force with which the ram will be pressed upwards by the water driven under it, we must consider that the pressure produced on each square inch of the section of the plunger will produce an equal pressure on each square inch of the ram. This is an immediate consequence of the fluidity of the water which is interposed between the plunger and the ram. If, then, as we have supposed, the section of the ram be 500 times greater than the section of the plunger, it will follow that a pressure of one ton exerted by the plunger will produce an upward pressure of 500 tons upon the ram.
Such is the general principle and such the essential parts of the hydraulic press, of which so stupendous a specimen is presented to the visitor in the machine which raised the Britannia tubular bridge from the surface of the water and placed it on the piers at a height of 120 feet.
The weight and bulk of this cyclopean engine are in accordance with its vast mechanical power. The great cylinder is 9 feet long, 22 inches in