SAFFLOWER. 371 



nate. 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 consider- 

 able effervescence, and therefore care must be taken 

 that the acid be added gradually, 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 neutral- 

 ized 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 

 precipitate appears in the form of a fine powder. 

 The supernatant liquor is then decantered, 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 preserved in a mass by 

 merely drying the precipitate, It is then called 



