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to the prolonged axis of the machine an arm, carrying a leaden weight of such magnitude as would counterbalance the weight of the harness.

The apparatus, thus improved, continued for a long time to prove of great usefulness in figure weaving. It detracts nothing from the merit of the inventor and improvers of a machine which removed so many of the disadvantages attendant upon the system of figure weaving, as then usually practised, that another and a better system has since been imported from a neighboring country, which has occasioned the laying aside of the draw-loom and its attendant draw-boy, for the production of figured silk goods.

The contrivance whereby this new system has been accomplished is the invention of M. Jacquard, who was a practical weaver of Lyons. Bearing his name, it will probably prove a lasting record of his mechanical talent, and will secure for his memory that fair harvest of fame, which, unhappily, he has not lived to reap, having fallen an early victim to the intensity of his mental application.

In the course of the very few years which have elapsed since its first introduction into this country, the Jacquard loom has entirely taken the place of every other method of figured silk weaving, and has been, in no small degree, instrumental in bringing that curious and beautiful art to its present state of advancement. The elaborate specimens of brocade which used to be brought forward as evidence of skilfulness on the part of the Spitalfields weavers of former days were produced by only the most skilful among the craft, who bestowed upon their performances the most painful amount of labor. The most beautiful products of the loom in the present day are, however, accomplished by men possessing only the ordinary rate of skill, while the labor attendant upon the actual weaving is but little more than that demanded for making the plainest goods. The carefulness and skill now required in preparing the various arrangements of the harness in the loom, or, to use the technical phrase, in building the monture, are out of all proportion less than were called for before the introduction of Monsieur Jacquard's invention, the principle and operation of which will appear from the following drawings and description.*

The apparatus is fixed on the top of the loom, in a perpen

*The drawings inserted for the elucidation of the Jacquard machine are merely outlines; a mode of delineation which is necessary, in order to render apparent its internal construction and action, which are concealed in the actual machine by the framing wherein the apparatus is contained.

dicular line with its harness, which is attached to the lifting hooks a a. These hooks are passed perpendicularly through eyes in an equal number of horizontal needles bc, which lie in rows in the frame d d. Of these lifting hooks and needles, only eight are shown in the drawings, in order to simplify the description; whereas, in the actual machine, there are as many as 400 of each, or fifty in each one of the eight rows, forming as many leases or lashes in the warp. The horizontal needles b c protrude through the frame d d at c, and are kept in that position by helical or spiral springs e e, placed in Fig. 18.

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cavities in the frame d, and there confined by vertical wires f, so that any degree of pressure being applied against the points of those needles at c will cause them to retire into the frame d d, and, on the removal of this pressure, the elasticity of the springs will again drive the needles forward. The range allowed for this horizontal movement of the needles is limited by vertical pins g, passing through loops made in the needles, and which stop them at a certain point. Close to these vertical pins, others are placed horizontally, upon which the loops of the needle slide, and by means of which they are retained in their proper position. One of the needles is shown separately, for clearer elucidation.

Above the frame d d is another frame h, having bars

ranged horizontally at right angles with the needles, and in number equal to the rows of lifting hooks. This frame h is alternately raised from or lowered upon the frame d d, by a lever attached to and acting with the treadle, and the length of the lifting hooks is so adjusted, that when the frame Fig. 19.

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h is lowered the lifting bars would so insinuate themselves under the curved ends of the lifting_hooks as to raise them when the frame h is again raised. For this purpose, the lifting bars, which in shape are something like blunted knife blades, have their broad parts a little inclined out of the perpendicular, so that their lower edges shall not strike in their descent against the curved extremities of the lifting hooks, while, by their continued depression, the flat parts of the bars will come in contact with those curves, and force the hooks somewhat back against the springs. These, at the moment they are freed from the pressure by the descent of the bars below the curves, force the hooks back into the vertical position, which insures their being suspended on the lifting bars with the upward movement of the frame h.

It will be observed that half the number of lifting hooks are attached to the lifting bars, while the other half remain disconnected with them; this has been effected by the forcing back of the needles, through the eyes of which those lifting hooks are passed, and which, by that act, are thrown out of their perpendicular, and are thus carried out of the range of the lifting hooks. All, therefore, that is further wanting to govern the raising and depressing of the different portions of the warp is a system for managing the retirement of the proper needles within the frame d d, and, consequently, for influencing the taking up of the proper heddles by means of the horizontal lifting bars.

This system of management is effected by the agency of a Fig. 20.

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square revolving bar, and a succession of perforated cards or slips, which are carried round with its revolutions.

The revolving bar is perforated on each of its four sides, with holes, answering, in number and position, to the points of the needles at c; and one or other of these sides is brought into contact with that same part of the frame d, at each depression of the treadle.

In the absence of the cards or slips, the points of all the horizontal needles b c would enter into the perforations of the revolving bar, and every one of the lifting hooks would be taken up on the lifting bars; whence the office of the cards becomes apparent. These are partially perforated, in such a manner as to make out the intended pattern by means of the partial influence they are made to exert in causing the retirement of the horizontal needles. It will be seen, by reference to the cards or slips, that their perforations are not so numerous as those on the sides of the revolving bar, and that

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these holes occur at irregular positions. If, then, one of these slips of card be made to cover the side of the revolving bar which is opposed to the points of the needles, such of the latter as do not coincide with the perforations made on the slip will be driven back against their helical springs. Their lifting hooks will, consequently, be carried beyond the range of the lifting bars; while all those needles which find coinciding perforations in the card slip will pass through it into the perforations of the revolving bar; their lifting hooks will, on the depression of the frame h, be engaged by the lifting bars; and those portions of the harness which are connected with them will be drawn up.

The perforations in the slips are so placed as to occasion that succession in the raising of the harness which will make out the intended pattern. For this purpose it is necessary to have as many cards or slips as there are required threads of shoot to make out or complete the pattern; this number of cards, where the pattern is large, or of great variety, is very considerable. The whole of them are fastened together by threads at their extreme ends or corners, in the manner shown in the drawing; and they thus form a kind of endless

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chain, one complete revolution of which makes out the pattern, which the continued working of the loom repeats to the end of the warp.

The revolutions of the card slips with the revolving bar, and the precision with which they must take their position upon it, so as to cause the coincidence of their perforations, is provided for by conical studs i i upon the revolving bar, upon which studs the slips adjust themselves by means of the larger perforations jj made in them for that purpose.

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