628 



CALICO-PRINTING 



the strength and nature of the mordants to be dunged ; usually a little chalk is added 

 sufficient to make the liquid slightly milky. The first compartment is either set with 

 the same solution, or sometimes -with a more concentrated one. The temperature 

 varies from 150 F. to boil, according to the style under treatment. On leaving 

 the cistern they pass successively through two or more becks, very similar to dye- 

 becks (which see farther on) where they run spirally through a solution of arseniate 

 of soda, much weaker than that of the fly -dung cistern, generally about 8 to 1 2 grains 

 arsenic acid per gallon ; to which some printers add a little cow-dung or bone-size 

 solution. The time occupied in the transit of a piece through the second dung becks 

 is from 20 to 30 minutes, and the temperature from 160 to 170 F. Fig. 374 shows 

 a plan and sectional elevation of two second dung becks ; the piece is brought from the 



373 



mfiflflURftnflft] ' P P. B R i"! R p Hfl n i I 



first dung cistern and entered into the end of one of the second dung becks, over the 

 roller A, and under the steam-pipe B, being drawn through the entire length in a spiral 

 and progressive manner ; a few yards of cloth are left lying at the bottom of the cistern 

 each time it passes over the roller A ; B is the perforated steam-pipe for heating the 

 liquid ; c, the drawing shaft for giving motion to the draw-roller A. On leaving the 

 first second dung beck, the pieces pass in a similar manner through the second, or 

 others, if more than two; they next pass through a washing machine. Fig. 375 

 is a section of the washing machine now most generally used for all purposes in print- 

 works ; A, the framing and wooden trough of the machine ; B, large roller for drawing 

 the cloth through machine ; c, pressing roller above roller B ; D, square beater roller, 

 running in a contrary direction to the cloth, at about 180 revolutions per minute ; E, wince 

 roller; F, perforated water-pipe; o, peg rail; H, plaiter wince; i, cloth passing through 

 the machine ; it enters at one end, and passes spirally through to the delivery end. 

 The advantages of this machine are, great simplicity and efficiency. The square bowl 

 causes the cloth to rise and fall upon the surface of the water, which, being allowed 



