[9]Mr. T. P. Shepard gives in his valuable “Receipts for Calico Printing,” published in 1872, the following:—NO. 52. INDIGO PRECIPITATE FOR FAST BLUE AND GREEN.10 pounds quicklime, slacked with6½ gallons water; then2 pounds ground indigo finely rubbed in water are stirred in; then add6 pounds copperas dissolved in 5 gallons of water; then add5 gallons hot water and15 gallons cold water.Stir well from time to time, until the liquid has assumed a yellow color and deep blue veins or streaks appear on its surface. When this moment arrives, draw off the clear liquor, and precipitate every ten quarts of it with½ pound tin crystals, dissolved in ½ pound muriatic acid.To the remainder of the mixture of lime and indigo, 15 gallons of water may be added, and the whole stirred; and when settled, the indigo may be precipitated from the clear liquor as before. This operation may be repeated a second time before all the indigo is exhausted.The indigo precipitate is to be collected on a muslin filter, and well squeezed out.
Mr. T. P. Shepard gives in his valuable “Receipts for Calico Printing,” published in 1872, the following:—
NO. 52. INDIGO PRECIPITATE FOR FAST BLUE AND GREEN.
The indigo precipitate is to be collected on a muslin filter, and well squeezed out.
[10]Guernsey Blue.—The darkest of the Nicholson Fast Blues. On a bottom of barkwood, camwood, madder, or inferiorindigo, produces an indigo blue which will stand all the acid tests the same as colors made from indigo.Serge Blue.—It will be found very serviceable to give bloom to goods dyed with indigo, and by itself shows a very good indigo test with nitric acid.—Instructions for Working the Atlas Works Aniline Dyes.
Guernsey Blue.—The darkest of the Nicholson Fast Blues. On a bottom of barkwood, camwood, madder, or inferiorindigo, produces an indigo blue which will stand all the acid tests the same as colors made from indigo.
Serge Blue.—It will be found very serviceable to give bloom to goods dyed with indigo, and by itself shows a very good indigo test with nitric acid.—Instructions for Working the Atlas Works Aniline Dyes.