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DYEING AND CALICO PRINTING.

The furnishing-rollers are moved by gearing with pinions on the axes of therollers 8, 8.

The working of the perrotine may be described as follows :—The piecemoves on a length equal to the breadth of the pattern-blocks, along with theblanket and back-cloth. The portion of the piece which issues from the thirdblock is fully printed ; what was under the second advances under the third ;what was under the first moves to the second, whilst a fresh portion ofwhite calico comes up to the first. While the calico is thus moving thesieves take the place which they hold in Fig. 24 ; the first on the righthand rises, the second moves from left to right, and the third is lowered. Allthree press on the furnishing-rollers, 8, where they take up the colour whichhas been spread evenly by the brushes, 9. Meantime the sliding block-holdersmove forward, and push the blocks against the sieves, so as to furnish themwith colour. At the same time the slides give the blocks a gentle movementbackwards, while the sieves deviate from their position. The blocks thenreturn, and are drawn back after having been pressed to a fresh part of thecolour surface. When these movements have simultaneously taken place theaction proceeds, the colour-sieves move back from before the blocks, and theseare pushed up against the latter, and print that part of the calico which isstretched upon them. The machine is now again at the point at which thedescription began.

The perrotine, as will be plain from the above description, is adapted forpatterns containing three distinct colours. It is extensively used in Franceand Belgium, one machine doing the work of twenty skilled block-printers.It executes some styles of work which the cylinder machine cannot executewithout the aid of the surface-roller.

In England the perrotine is in much less general use than in France.The cylinder-machine, on the contrary, a Scotch invention, has receivedits chief development in this country, and, except for a few particularstyles, has quite displaced hand-printing. One of them, managed by oneman, assisted only by two boys who attend to the colour troughs, performs asmuch work as two hundred men and boys could do with the blocks. In somestyles a mile of cloth can be printed hourly by a single machine.

The following diagram gives a general idea of this system of printing(Fig. 26). The design to be printed is engraved on the surface of a hollowcopper roller, which is forced by pressure upon a stout mandrel of iron, whichserves it for an axle. To aid the transfer of the pattern to the calico to beprinted, the pieces are lapped around another large cylinder, which is renderedelastic by a coating of stout woollen cloth. The pattern-roller presses thecalico against this elastic cushion, and consequently prints it as it revolves.In the engraving A is the pattern-roller mounted on its mandrel, which receivesrotatory power from a wheel at its end, in connection with the steam or waterpower of the works. B is a large iron drum, turning in bearings of the endframes of the machine. The pattern-roller, A, is pressed against this drumby weights or screws, the weights acting steadily upon its brass bearings bylevers. Round the drum, b, an endless web of felt or blanket travels in thedirection of the arrow, and is carried round by the drum, B, which again isturned by the friction of the cylinder, A. c is a wooden roller, covered withcloth, and partly plunged in the colour mixture of the trough, d d. c is