Fig. 861 exhibits a longi tudinal section of the soften ing-machine, by means of which this is accomplished. It consists of four rows of rollers, 10 in each row, which are superimposed on each other. These rollers are 9 in. in diameter, and 2 ft. 6 in. in length. They are deeply fluted, as may be seen in Fig. 862, which is upon a scale of ith the size of the object ; they are held in position by their axles being inserted in vertical slots in the side of the frame. The top roller rests upon the second, these two upon the third, std the whole three upon the bottom one. A feed-apron a is attached to the front of the machine. Over the top, are placed two cisterns k 1, the first of which ism reservoir of water, and the second of oil. Each of these contains a revolving roller mn, which dips half its circumference into the fluids. Impinging against the upper surface, is a " doctor " or scraper o p, ex tending across the length of E the roller, and the outer edge ° of which passes beyond the cistern. This is arranged to form an inclined plane, the lower edge being that away from the roller. At the extremity of the machine, are a pair of delivery-rollers, the bottom one of which is fluted, the superincumbent one being plain.
The process is as follows :—The " stricks," or handfuls of jute, are evenly fed upon the travelling apron a, which is actuated by the three rollers b, and travels in the direction of the arrow, the layer of fibre passing between the rollers c d, thence along the series, around the last of which it descends to retrace its course to the front of the machine, coming out between the rollers d e, down the front of which it again descends, and passes between the third and the bottom series, emerging from bet wcen the delivery-rollers g A. It will be observed that, when the fibre passes between the rollers a b, it is subjected only to the weight of the upper row of rollers; on its return, this weight is doubled, as the fibre is then passing under the two upper rows, after doubling from which, it is subjected to the weight of the three uppermost rows of rollers. The action of the corrugated surfaces of the rollers is also assisted by a slight lateral traverse, which is imparted to them to increase their effect.
Formerly jute was subjected to a process called " batching," in which the fibre was spread in layers, and sprinkled with oil and water, afterwards being left for several days, so that the mass might become uniformly permeated by the moisture, and thereby softened for the card. This is now more efficiently performed by means of this machine, with its attachment, as mentioned above, consisting of the water-cistern k, and the oil-cistern 1, which, by means of the revolution of their respective rollers, discharge their contents upon the jute, as it is passing between the first rows of rollers. The even distribution of the oil and water, which is thus secured, and to which is added
the further distributive effect of the lateral motion of the rollers, so uniformly moistens the mass of the fibre, that the necessity of allowing it to lie in heaps for several days is obviated. The softening process having been completed, the fibre is weighed into bundles, and conveyed to the card.
Carding.—In the first or breaker card, the length of the fibre, naturally 6-7 feet, is broken down to 14-18 in., which length it retains until it reaches the spinning process. The essential parts of the breaker card are shown in section in Fig. 863, and consist of a revolving feed•lattice or apron a ; a feed-roller b, which possesses a concentric plate or shell c, placed on its lower side; the main carding-cylinder d, of about 4 ft. diameter and 6 ft. wide on the working surface, which is covered with strong steel cards or pins, arranged so as to incline slightly in the direction in which the cylinder revolves (Fig. 864); two pairs of workers and stripper-rollers e f, each pair having a tin roller g, for pressing the fibre into the card of the stripper to prevent its falling, and ensure its being carried around its periphery until delivered to the main-cylinder again ; a doffer-cylinder ; doffing-rollers k ; conductor 1; delivery-rollers m; and sliver-can n.
In the operation of this card, the strioks of jute are evenly laid by the attendant upon the endless feed-apron a, with their foot- or root-end foremost, all joints being carefully broken. The movement of the apron conveys it to the feeder b, whose surface speed being only about 10 ft. a minute, the fibre is drawn slowly forward, and pressed into the teeth of the roller by the con centric plate c. As the feed-roller revolves, the fibre is presented to the action of the main carding cylinder d, the surface revolution of which, being at the rate of 2000 ft. a minute, strikes the fibre with great force in a downward direction, thereby combing and dividing it very efficiently before the feeder and the concentric plate relinquish their hold. It is also obvious that a large quantity of the fibre will be broken or torn away by the great rapidity and severe action of the main oylinder. These portions, being carried on the card-points of the cylinder, are caught by the workers and strippers, and are opened and combed by their action.