512 



HISTORY OF THE VEOETABLE KINGDOM. 



in a poor dry ground the plants bloom at an 

 earlier period, but the flowers of these are smaller, 

 and yield a less portion of colouring matter. A 

 moderately dry and well manured soil is con- 

 sidered to be on the whole best adapted to the 

 culture of this plant, especially if the seed be 

 so^vn early in February. 



The moment the flowerets which form the 

 compoundflowersbegin to open, they are gathei'ed 

 in succession without waiting for the whole to 

 expand, since when allowed to remain till fully 

 blown, the beauty of the colour is very much 

 faded. As the flowers are collected they are 

 dried in the shade. This work must be carefully 

 performed, for if gathered in wet weather, or 

 badly dried, the colour will be much deteriorated. 

 These flowers contain two kinds of colouring 

 matter, — the one yellow, which is soluble in 

 water, the other red, which being of a resinous 

 nature, is insoluble in water, but soluble in 

 alkaline carbonates. The first is never converted 

 to any use, as.it dyes only dull shades of colour: 

 the other is a beautiful rose-red, capable of dye- 

 ing every shade, from the palest rose to a cherry- 

 red. It is therefore requisite, before these flowers 

 can be made available, to separate the valueless 

 from the valuable colour; and since the former 

 only is soluble in water, this operation is matter 

 of little difficulty. 



The flowers are tied in a sack and laid in a 

 trough, through which a slender stream of water 

 is constantly flowing; while, still farther to pro- 

 mote the solution of the yellow colouring matter, 

 a man in the trough treads the sack and subjects 

 every part to the action of the water : when this 

 flows without receiving any yellow tinge in its 

 passage, the washing is discontinued, and the 

 saflBower, if not wanted for immediate use, is 

 made into cakes, which are known in commerce 

 under the name of stripped safilower. It is 

 principally used for dyeing silk, producing 

 poppy-red, bright orange, cherry, rose, or flesh- 

 colour, according to the alteratives employed 

 in combination. These are alum, potash, tartar, 

 citric acid, or sulphuric acid. 



A smaller variety of the cartliamus is culti- 

 vated in Egypt, where it forms a considerable 

 article of commerce. "The dyes the Egyptians 

 use," says Volney, "are probably as old as the 

 time of the Tyrians, and they carry them at this 

 day to a perfection not unworthy that people; 

 but their workmen, jealous of the art, make an 

 impenetrable mystery of the process." Hassel- 

 quist, in his Voyage d'Egypte, describes the 

 manner in which the Egyptians prepare the 

 cartliamus for use. As soon as the flowers are 

 gathered, they are squeezed between two stones 

 to extract all their moisture; they are then 

 washed several times with pit well water, which 

 in Egvpt is naturally brackish. On being taken 

 out of the water they are pressed between the 



hands, and then spread out on mats upon ter- 

 races; they are covered during the day lest the 

 drying should be too quickly completed, and 

 they are exposed to the dews of night. Every 

 part is turned over from time to time, and when 

 found to be dried to the proper point, the whole 

 is taken up and preserved for sale. 



The colouring matter from the stripped saf- 

 flower is obtained by the application of an 

 alkaline carbonate. On being soaked in a weak 

 solution of barilla it speedily colours the fluid 

 of a deep red. When the whole of the colouring 

 matter is thus extracted and held in solution by 

 the alkaline menstruum, the infusion is strained. 

 It now remains to precipitate the colour, for 

 which purpose acid is added in sufficient quantity 

 to saturate the alkali employed. Citric acid or 

 fresh lemon juice is generally chosen, because it 

 renders the colour more lively than when in 

 combination with any of the other acids. The 

 carbonic acid gas, which is disengaged during 

 the saturation of the alkali, of course produces 

 considerable effervescence, and therefore care 

 must be taken that the acid be added gradual^, 

 and that the dimensions of the vessel are such 

 as to allow of the ebullition without the liquor 

 running over. The colouring matter extracted 

 from the safflower being only kept in solution 

 by the action of the alkali, it is of consequence 

 separated, as this becomes neutralized by the 

 acid, and it fixes on the sides and bottom of the 

 vessel. Most generally, however, carded cotton 

 is introduced into the fluid previously to the 

 application of the acid, and as the colouring 

 matter has more affinity for the cotton than for 

 the surface of the vessel, it fixes upon that as it 

 separates from the alkali. It is scarcely possible 

 wholly to separate the yellow colouring matter 

 in the first washing, and the part which remains 

 renders the shade of colour given to the cotton 

 rather dull, but this is easily removed by repeated 

 washings. If no cotton is employed the pre- 

 cipitate appears in the form of a fine powder. 

 The supernatant liquor is then decanted, the 

 colour washed and distributed upon saucers, 

 where, as it dries, it acquires a coppery tinge; 

 the rose-red colour is produced as soon as this 

 is wetted. The resinous part may also be pre- 

 served in a mass by merely drying the precipi- 

 tate. It is then called India or China lake. It 

 does not cotnmunicate any colour to water, 

 but produces abeautiful red tincture when alcohol 

 is poured upon it. This colouring matter, mixed 

 with French chalk, or talc, finely pulverized, is 

 the substance known under the name of vegetable 

 rouge. 



To render this substance efficient for dyeing, 

 it must be again held in solution by an alkaline 

 menstruum, in which the stuff' to be dyed is 

 immersed, and by the application of the acid the 

 colouring matter is precipitated on the fabric 



