. A practical handbook of dyeing and calico-printing. With eleven page-plates, forty-seven specimens of dyed and printed fabrics, and thirty-eight woodcuts . Nicholsons Blue (4 B.) hours it still amounts to 4 atmospheres. A tube is then fixed to the screw-tap, which leads to a worm, communicating with a series of large globes, andthe distillation is begun. When the distillation is at an end the boiler is opened, and the semi-fluidcontents are drawn out, and put to dissolve in a boiler containing 600 litres ofdistilled water and fitted with a steam-jacket. The green dissolves entirely,whilst th
. A practical handbook of dyeing and calico-printing. With eleven page-plates, forty-seven specimens of dyed and printed fabrics, and thirty-eight woodcuts . Nicholsons Blue (4 B.) hours it still amounts to 4 atmospheres. A tube is then fixed to the screw-tap, which leads to a worm, communicating with a series of large globes, andthe distillation is begun. When the distillation is at an end the boiler is opened, and the semi-fluidcontents are drawn out, and put to dissolve in a boiler containing 600 litres ofdistilled water and fitted with a steam-jacket. The green dissolves entirely,whilst the violet matters remain insoluble, with the exception of a smallquantity which is kept in solution by the acid set free during the residue is removed by a first filtration. To the filtrate about 35 kilos, ofcommon salt are added ; the boiling is continued, and the free acid isneutralised by crystalline carbonate of soda. To regulate the quantity, a. Saffranine Pink. 204 DYEING AND CALICO PRINTING. small portion of the liquid is taken and filtered over sand. When the filtrateruns through a fine green, without any mixture of hlue or violet, the additionof carbonate of soda ceases, ij to if kilos, of crystals being generally suffi-cient. The whole liquid, when cold, is now filtered over sand, to remove blueand violet matters. The filtrate is precipitated by a cold saturated solution ofperfectly pure picric acid. For the proportions taken, 346 kilos, of picric acidwill be required. The picrate formed is but sparingly soluble in water, and isconsequently thrown upon a common filter and slightly washed. The preci-pitate is a very fine paste. It is allowed to drain till sufficiently dyer is obliged to make use of a small proportion of alcohol in dissolvingthis green. Soluble preparing this colour we substitute for the picric acid the sulphate, chloride,or acetate of zinc; there are thus obtained double salts of
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectdyesanddyeing, bookye
