2626. Black Lustre Color for Paper, Cloth, or Wood

2626.    Black Lustre Color for Paper, Cloth, or Wood. Dr. Kiehmeyer gives a receipt which is adapted for either paper, cloth, or porous wood. He states that it stands well,' is very supple, and has no tendency to get sticky. To prepare it, boil together 8 pounds glue, previously dissolved in 1(5 pounds water; 1 pound potato starch, dissolved in 51/2 pounds water; 51/4 pounds campeachy extract of 6° Baum'e; 1 pound 2 ounces green vitriol, and

83/4 pounds brown glycerine. "When thoroughly mixed, remove the pot from the fire, and continue to stir until the liquid is cold. If the paint bo desired thicker or thinner, the amount of starch and glue must be varied as well as the other materials, or the lustre will suffer.

2627. Black Produced by the Mixture of Colorless Liquids

2627.   Black Produced by the Mixture of Colorless Liquids. One of the most interesting phenomena in the operations of chemistry occurs in the decomposition of sulphate of iron by gallic acid. Into a wine-glass, containing the infusion of galls, pour a solution of the sulphate of iron. The gallic acid, from its superior elective affinity to the iron, detaches it from its former combination with the sulphuric acid, and in a short time these two fluids, previously colorless, become intensely black. To make this black fluid into ink, nothing but a little gum is required, to retard the precipitation of the coloring matter.

2628. To Make Liquid Blue

2628.      To Make Liquid Blue. Put into a bottle 1 ounce pure Prussian blue, in fine powder, and pour upon it 2 ounces concentrated hydrochloric acid. Effervescence ensues, and the mixture soon assumes the consistence of a thin paste. Leave it for 24 hours, and then dilute with 8 or 9 ounces water, and bottle it. The whole may be further diluted with a quart of water and still retain a sufficiently dark color for washing muslins, etc. The common blue writing fluid is thus prepared.

2629. Carmine Purple

2629.    Carmine Purple. The dye recently invented, and known as carmine purple, is obtained by the solution of uric acid in nitric acid, care being taken to prevent boiling over and too great an increase of temperature. The mixture should remain standing quietly for some days, after which a thick, pasty, or doughy substance is obtained, which is to be treated with warm water, filtered, and the residuum again treated with warm water. The filtered liquid possesses a reddish or yellowish color, resulting from the organic substances decomposed by the nitric acid. It is next to be evaporated in a large enameled iron vessel, but not heated to the boiling point, which would destroy the murexide (carmine purple) produced. After the liquid has been evaporated to a syrupy consistency, and has assumed a beautiful brownish-red or violet color, it is to be allowed to cool. The entire quantity of the liquid should never be evaporated at one time, nor heated to the boiling point.