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Bandannas

press, liquor, cloth, water, cylinder, lead, plate, pattern, block and plates

BANDANNAS. A name given to a certain description of silk handker. chiefs manufactured in the East Indies, the patterns of which generally consist of square or circular spots, variously arranged upon a red, blue, or yellow ground. An imitation of these handkerchiefs upon cotton, produced by first dying fine calico of a brilliant Turkey red, and after discharging the colour from those parts which, in the pattern, are white, by means of hquid chlorine, now forms a considerable branch of the cotton manufacture of this country, and an important article for exportation. A correct account of this process will be found in the following description of the great bandanna gallery, in the Turkey red manufactory of Messrs. Monteith & Co. of Glasgow, who obtained a patent for the process. Their new arrangement of their hydrostatic presses in their discharging gallery, was completed in 1818, under the direction of Mr. G. Ridger, Ben. manager of the works. It consists of sixteen of these engines, beautifully constructed, placed in subdivisions of four; the spaces between each set serving as passages to admit the workmen readily to the back of the press. Each subdivision occupies 25 feet ; hence the total length of the whole appa ratus is 100 feet. To each press is attached a pair of patterns in lead (or plates u they are called) in which all those parts of the design which are to be white are cut away, so as to form recesses in the plates. One of these plates is at tached to the upper block of the press, which block turns on a kind of universal joint, so as to apply exactly to the under plate. The latter rest on the sill or movable part of the press ; when this is forced up, the two patterns close on each other with the greatest nicety, by guide pins at the corners fitted with the utmost care. The power which impels this great hydrostatic range, is placed in a separate apartment, called the machinery room. This machinery consists of two cylinders of a peculiar construction, called the prime cylinder, having pistons very accurately fitted to them. To each of these cylinders three small force-pumps, worked by a steam engine, are connected. The piston of the larger cylinder is 8 inches in diameter, and is loaded on the top with a weight of S tons ; it can rise through a space of 2 feet. The piston of the other cylinder is only 1 inch in diameter, and is, likewise, loaded with 5 tons, and can also rise through a space of 2 feet. The pistons being at their lowest point, water is in jected by the force-pumps into the prime cylinders, until the loaded pistons have arrived at their highest points, in which state they are ready for working the hydrostatic discharge presses; the water-pressure being conveyed from one apart ment to the other, through strong copper tubes of small calibre passing beneath the floor. Two valves are attached to each press, one opening a communication between the large prime cylinder and the press cylinder, and the other between the small prime cylinder and the press. The function of the first is simply to lift the under block of the press into contact with the upper block : that of the secofid, to give the requisite compression to the cloth. A third valve is attached to the press for the purpose of discharging the water from its cylinder, when the press is to be relaxed in order to remove or draw through the cloth. From twelve to fourteen pieces of cloth previously dyed Turkey red, are stretched over each other as parallel as possible, by a particular machine. These parallel layers are then wound round a wooden cylinder, or drum, which is then placed at the back of the press. A portion of the four teen layers of cloth, equal to the area of the plates, is next drawn through between them, by hooks attached to the two corners of the web. On opening the valve connected with the 8-inch prime cylinder, the water enters the press cylinder, and instantly lifts its lower block, so as to apply the under plate with the cloth close to the upper one. This valve is then shut, and the other is opened. The pressure of 5 tons in the 1-inch prime cylinder is now brought to bear on the piston of the press, which is 8 inches diameter. The eflbctive force here, therefore, will be 5 tons X 8=320 tons, to compress the cloth between the plates. The next step is to admit the bleaching or discharg ing liquor (aqueous chlorine, obtained by adding sulphuric acid to the solution of chloride of lime) to the cloth. This liquor is contained in a large cistern in an adjoining house, from which it is run at pleasure into small lead cisterns at tached to the presses ; which cisterns have graduated index-tubes for regulating the quantity of liquor according to the discharge pattern. The stop-cocks on the pipes and cisterns containing this liquor, are all made of glass. From the measure cistern the liquor is allowed to flow on to the surface of the upper plate, and percolating through the portions of the cloth which lie under the open parts of the pattern, it extracts the Turkey red dye. The liquor is finally conveyed to the waste-pipe from a groove in the under block. As soon as chlorine liquor

has passed through, water is admitted in a similar manner to wash away the remains of it ; otherwise, on relaxing the pressure, the outline of the figure discharged would become. The passage of the discharge liquor, as well as of the water, is occasionally aidedby a pneumatic apparatus, or blowing machine, consisting of a large gasometer, from which air, subjected to a moderate pressure, is allowed to issue and act in the direction of the liquid in the folds. By an occasional twist of the air stopcock, the workman can also ensure the equal distribution of the over the whole excavations in the upper plate. When the demand for goods is pressing, the air apparatus is much em ployed, as it enables the workman to double his product. The time requisite for completing the discharging process, in the first press, is sufficient to enable the other three workmen to put the remaining fifteen in opera tion. The discharger proceeds now from press to press, admits the liquor, the air, and the water ; and is followed, at a proper interval, by the assistants, who relax the presses, move forwards another square of the cloths, and then restore the pressure. When the sixteenth press has been liquored, it is time to open the first press. In this routine, about ten minutes are employed ; that is, 224 handkerchiefs (16 X 14) are discharged in ten minutes. - The whole cloth is successively drawn forward to be treated in the above method. When the cloth escapes from the press, it is passed between two rollers in front, from which it fills into a trough of water placed below. It is finally carried off to the washing and bleaching department, where the lustre both of the white and the red is considerably heightened. By the above arrangement of presses, 1600 pieces of 12 yards each=19,200 yards are converted into bandannas in the space of ten hours, by the labour of four workmen. The following engraving exhibits an elevation of one of the presses. a is the top of the entablature; b b b cheeks of ditto, or pillars ; c upper block for fastening the upper pattern to ; d lower or movable block ; e the cylinder ; f the sole or base ; g the water trough for the discharged cloth to fall into ; h k tubes to admit the water; i tube for the air; j cock to admit the liquor from the meter ; k cistern, or liquor meter, having two glass tubes for indicating the quantity of liquor in the cistern; 11 glass stop-cocks for admitting the liquor into the cistern ; o o stop-cocks for admitting water; pp pattern plates ; q q screws for setting the patterns parallel to each other; the snuffs are perforated with a Finch drill ; the lower frame has pins corresponding with these perforations, so that the patterns are guided into exact correspondence with each other; r r rollers, which receive, and pull through, the discharged cloth, from which it falls into the water trough ; • stop cock for filling the trough with water ; t t t waste tubes for water and liquor. The patterns, or plates, which are put into thepresses to determine the white figures on the cloth, are made of lead, in the following way : A trellis frame of cast iron, one inch thick, with turned-up edges, forming a trough rather larger than the intended lead pattern, is used as the ground work. Into this trough is put a lead plate, and firmly secured by screws passing from below. To the edges of this lead plate, the borders of the piece of sheet lead which covers the whole outer surface of the frame are soldered: thus a strong trough is formed, about one inch deep. The upright border gives strength to the lead plate, and serves to confine the liquor. A thin sheet of lead is now laid on the thick plate of lead, and is soldered to it round the edges. Both sheets must be made very smooth beforehand, by hammering them on a smooth stone table, and then finishing them with a plane. The surface of the thin sheet (now attached) is to be covered with drawing paper pasted down upon it, and upon this the pattern is to be drawn. It is now ready for the cutter, who, in the first place, fixes down with brass pins all the parts of the pattern which are to be left solid. He then proceeds with the little tools used generally by block cutters, which are fitted to the different curvatures of the pattern, and cuts perpen dicularly quite through the thin sheet. The pieces thus detached are easily lifted out, and thus the channels are formed which design the white figures on the red cloth. At the bottom of the channels a sufficient number of small perforations are made through the thicker sheet of lead, so that the discharging liquor may have free ingress and egress. Thus one plate is finished, from which an impression is to be taken, by means of printers' ink, on the paper pasted on another plate ; the impression is taken in the hydrostatic press. Each pair of plates constitutes a set, which may be put into the presses, and removed at pleasure.