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Home › Recipes › To make chemic blue and green
To make chemic blue and green
Chemic for light blues and greens, on silk, cotton, or woollen, and for cleaning and whitening cottons, is made by the following process:-- Take 1 lb. of the best oil of vitriol, which pour upon 1 ounce of the best Spanish flora indigo, well pounded and sifted: add to this, after it has been well stirred, a small lump of common pearlash as big as a pea, or from that to the size of 2 peas, this will immediately raise a great fermentation, and cause the indigo to dissolve in minuter and finer particles than otherwise. As soon as this fermentation ceases, put it into a bottle tightly corked, and it may be used the next day. Observe, if more than the quantity prescribed of pearlash should be used, it will deaden and sully the colour. Chemic for green, as above for blue, is made by only adding one-fourth more of the oil of vitriol.
If the chemic is to be used for woollen, East India indigo will answer the purpose even better than Spanish indigo, and at one quarter of the price; but the oil of vitriol is good for both.