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DYEING AND CALICO PRINTING.

For goods containing much purple the soap solution consists of 8 kilos, ofwhite soap and 1320 litres of water: temperature, ioo®; duration of immer-sion, 1 minute. For goods with less purple the quantities are—Water, 1320litres ; white soap, 4 kilos.: temperature and time of immersion the same asabove.*

These operations—viz., washing, branning, and soaping—are not sufficientto bleach very completely the unmordanted or the white portions of the fabricwhich have taken up, even in garancin-dyeing, some colouring matter, althoughfar less so than is the case with crude madder. The goods are therefore sub-jected to the action of chlorine,—that is to say, run through a very weaksolution of bleaching-powder. Garancin-dyed articles are chlored twice;the first operation, steam chloring, consists in passing the goods first througha very weak solution of bleaching-powder, and immediately after through alarge tank filled with steam : the moist heat sets the chlorine (hypochlorousacid) free, and thereby causes the oxidation of the small quantity of colouringmatter adhering to the white portions of the fabric.

It need hardly be said that the solution of bleaching-powder should be sodilute as not to injure the tissue, even very fine muslins and similar fabrics,and also not to deteriorate the colours. The second chloring is effected bymaking the goods, after having been moistened with the solution of bleaching-powder, pass over a series of partly hollow cylinders, heated by means ofsteam, whereby, during the drying, the bleaching also is completed. We givebelow some receipts as employed for these purposes, but in this country theaqueous solution of chlorine is not very commonly used, owing to the faCtthat it is a less certain agent, unless prepared with great care and usedwithin a very brief time after it has been prepared.

For goods containing much purple the solution for the first chloring consistsof—50 litres of water; 2 litres of chlorine water; 16 grms. of ultramarine:the latter substance performs here the same functions as the various kinds ofblues used in the laundries. The second chloring solution consists of—Water,16 litres ; chlorine water, 2 litres ; ultramarine, 2*240 kilos.

For puce-brown coloured ground with a white pattern the first chloring ismade up of—12 litres of water ; 2 litres of chlorine water ; 15 grms. of ultra-marine. Second chloring solution :—Water, 16 litres ; chlorine water, 2 litres ;ultramarine, 1*120 kilos.

For grey dyed goods, first chloring liquid :—Water, 24 litres ; chlorinewater, 2 litres; ultramarine, 15 grms. Second solution:—Water, 120 litres;chlorine water, 2 litres ; ultramarine, 1*120 kilos.

For goods with much red, first solution :—Water, 40 litres ; chlorine water,

* The soap for clearing madder purples is generally 6eleCted less alkaline than that usedfor reds and pinks. For the former a good composition is—

Fatty acid .. .. .. .. 60*40

Soda. 5*60

Water. 34*00

100*00

For reds and pinks the following is preferable:—

Fatty acid. 59*23

Soda .. .. .. .. ... 6*77

Water. 34*00

100*00