58

DYEING AND CALICO PRINTING.

then lowered down. The weighting of these levers, which are partly outsidethe machine, is seen in Figs. 27 and 28. L are weights, Q colour boxes, theirbottoms and sides made of sheet-copper and the ends of gun-metal; in eachend is a slot to receive the brass journals of the wooden furnishing rollers, P,which are lapped with a few layers of coarse calico, and, revolving in thecolour and against the pattern-rollers, D, supply them equally all over with thecolour; any excess of colour being removed by the dodtors, T. These are thinblades of some appropriate metal, often steel, but sometimes German-silver,which are mounted in dodtor-shears, that is, plates of metal screwed togetherwith bolts. The shears have journals, which rest in bearings, movable back-wards and forwards by the screws, s ; the dodtors are kept in close contadtwith the pattern-rollers by levers and weights, for the arrangement of whichsee Fig. 29, where A B c are the levers attached to the dodtor-shears. Onthe ends of these levers weights are hung, and by this means the dodtors areforcibly pressed against the pattern-roller. After printing its pattern on thepiece the roller, d, is cleaned from dust or filaments by the lint-dodtors, u,pressed against the roller by the screw, s, Fig. 28. The colour boxes aremounted on wooden boards, and tightened up against the roller by the screws,w w and B R. The lower pair of colour boxes are removed from the copperroller when not in use by the handles, v, after removing the screws, w w.There is a toothed wheel slipped on to each mandrel, working into a toothedwheel on the axle of the furnishing-roller, which ensures the pattern-rollerand furnishing-roller always working together. By an excentric, fixed on theaxis of the pressure bowl and connedted with each colour dodtor, they receivea vibratory movement, which hinders them from being worn down irregularly.Sometimes in machines for more than four colours the colour box is dispensedwith, and a dodtor placed in a covered frame is applied to the pattern-rollerinstead. In this arrangement the dodtor forms the bottom of the colourreceptacle, and is strongly pressed against the roller, the curved frame stoppedoff at the sides with a piece of copper curved to fit both roller and frame, andwhich is padded with a piece of folded cotton cloth, forms the colour box.Such a box takes up little room and consumes little colour. The rollof calico is shown at a , wound on the wooden roller, b, the axle of whichrests in bearings at the end of the arms. The calico passes under a smallwooden roller, next over a square iron bar, and next against the scrimping-bar,Y, thence over the wooden roller, a , round which also pass the piece of greycotton, rf, and the woollen blanket, e. The scrimping-bar is made of iron orbrass with a curved surface furrowed by grooves, cut right and left from thecentre. By passing over this bar the cloth is stretched equally from thecentre, and creases are removed. To keep the piece constantly stretched theroller, b, is fitted with a wooden pulley, round which passes a leather strap,one end of which is secured to the framework, and to the other is attached aweight. The fridtion of the strap against the pulley produces a retardingadtion, and keeps the piece stretched.

Fig. 30 shows a 12-colour machine, and Fig. 31 a 20-colour, by Messrs.Gadd and Hill, of Manchester.

The surface roller machine executes similar styles of work to those pro-duced by the perrotine. Here the pattern-cylinder is in relief like the handblocks. Fig. 32 is an 8-colour machine of this class, by Messrs. Gadd andHill. A A is here the framework; b b the bowl or cylinder, which is hollow,