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. ------------------------------------------------------------- The deposit is made into a paste with gum water; a salt of tin is often added to prevent oxidation. It is important to prevent the transformation of the indigo white into indigotine before printing. This indigotine would not fix itself on the fabric. Moreover, after printing, it is necessary to hasten the dissolution of the indigo white to enable it to penetrate the fibre. It is sufficient for this end to pass it through milk of lime. The stannic combination is immediately destroyed; the colorable matter unites itself with the lime, and the color passes into a pale gray with apple green. The indigo white becomes momentarily soluble; but the presence of the excess of lime and the thickening, as well as the attractive affinity of the thickening, prevent any running. The piece on issuing from the lime water is placed in running water, when reoxidation commences, which this time fixes the color. The piece is finally passed through a sulphuric acid bath to absorb the lime, and washed. By adding to the color a salt whose base precipitates in the milk of lime and oxidizes in the running water, and replacing the simple acid bath by an acid bath with yellow prussite, the intensity of the blue is increased through the formation of Prussian blue. Although we have seen beautiful effects from the application of the solid blue of indigo on prints at our Pacific Mills, the colors produced by Prussian blue and aniline are so much more brilliant and easy of application that the use of indigo in printing goods for ordinary consumption is likely to decline rather than increase. It will be otherwise if we should ever manufacture for the East India markets. Here is a field still open for our manufacturers. Mr. Watson, in his beautiful work on “The Costumes of the People of India,” remarks that “British manufacturers have hitherto failed to appreciate Oriental tastes and habits, and hence supply but an insignificant part of the clothing of the two hundred million persons that form the population of what is commonly spoken of as India.” The great defect, he observes, is the want of stability of color in the cotton fabrics introduced,—this stability being an imperative demand in the Oriental markets.