2630. To Color with Alkanet Root

2630.    To Color with Alkanet Root. Anchusa Tinctoria gives a fine red tinge to oils, fats, wax, turpentine, spirits, essences, etc., and is used to color hair oil, pomatums, ointments, varnishes, etc. The spirituous solution stains marble of a deep red; wax tinged with alkanet and applied to warm marble, leaves a fresh color.

2631. To Color with Mallow or Malva Flowers

2631.   To Color with Mallow or Malva Flowers. The mallow or malva flower is a native of Europe, growing abundantly on waste grounds and by the waysides. It is also sometimes cultivated in this country. This flower, which gives a beautiful color to water, is used for coloring port and claret wines, and it is considered one of the best articles that can be employed for that purpose. Weigh 2 pounds, and steep the red petals in cold water for 5 or 6 hours. Tartaric acid mixed with the mallow gives a bright red color, and salt of tartar (carbonate of potassa) a deep purple red.

2632. To Purify Caramel

2632.    To Purify Caramel. The caramel of commerce is spirit coloring, or a solution of burnt sugar in water. (See .694.) In this state it is mixed with variable quantities of undecomposed sugar and certain bitter compounds. To render it quite pure, it should be dissolved in water, filtered, and alcohol added until it ceases to produce a precipitate. The caramel is thus thrown down, while the impurities remain in solution. Pure caramel is a black or dark brown powder, soluble in water, to which it gives a rich sepia tint; it is insoluble in alcohol, and incapable of fermentation.

2633. Blue Dye from Molybdenum

2633.    Blue Dye from Molybdenum. According to late experiments by Professor Boettger, based upon some previous researches of Dr. Schönn, if molybdic acid be dissolved to saturation in concentrated sulphuric acid with heat, an uncolored clear fluid is obtained, forming a double acid of sulphuric and molybdic acid. If a little of this double acid be placed in a porcelain dish and heated till it begins to throw off white vapors, and then a certain quantity of absolute alcohol be gradually added, a beautiful blue color is developed, as if by magic, by means of which silk can be dyed without the use of any mordant.

2634. Mordants

2634.   Mordants. Substances employed to fix the coloring matters of dye-stuffs on organic fibres, and to give them brilliancy and permanency. This they effect, either by their strong affinity for the fibre and the dye matter, serving as a bond of union between the two, or by uniting with, and rendering insoluble, the dye contained in the pores of the fibre. The principal mordants are alum, and the oxides of iron or tin. (See No. 93.)

2635. To Color Butter

2635.    To Color Butter. Pureannotto, when properly prepared, is very successfully used for imparting a good color to fall and winter butter. (See No. 2621 (Purified Annotto).) Annotto of course adds nothing to the flavor or quality of butter, but as the pure article, when thus employed for coloring, is quite harmless, there can be no serious objection to its use. In coloring butter with annotto it is important that a prime article be used, and to have it prepared so that it shall be free from sediment and adulteration.