(Z) Dark Blue

Christian Knab, Munchberg, Bavaria, makes a blue preparation good for marking trunks and boxes, because it readily combines with wood, cloth, etc., and resists the action of the weather. His process is given in the Deutsche Industrie Zeitung as follows: - 100 lb. of a 30 per cent, fluid extract of logwood are put in a suitable kettle, with 3 qt. alcohol, to which 2 lb. hydrochloric acid has already been added. The mixture is kept at 68° F. and well stirred until thoroughly mixed. Next he dissolves 10 lb. (yellow) chroroate of potassium in 30 lb. boiling water, and adds to it 20 lb. of hydrochloric acid, stirring well, and when it has cooled to 86° F., stirs it very slowly into the mixture already in the kettle. The whole is then warmed to about 185° F. The mass, which then becomes an extract, is stirred a short time longer, and to it is added 30 lb. dextrine mixed with 20 lb. fine white earth (terra alba), and well stirred through. The mass, when taken from the kettle, is put into a mill where it is thoroughly worked together.

It is lastly put into tin boxes, and left standing a long time to dry out. (aa) Blue.

Silver nitrate . 4 gram. Liq. ammonia . .12 „ Sodium carbonate . 4 „ Powdered gum-arabic. 6 „ Cupric sulphate . 20 „ Distilled water . 16 „ Dissolve the silver salt in the ammonia, and the soda, gum, and copper salt in the distilled water, and mix the two solutions. (Dorvault.) (bb) For marking bales.

Shellac ... 2 oz.

Borax .... 2 „

Water .... 25 „

Gum-arabic ... 2 „

Venetian red, sufficient to colour.

Boil the borax and shellac in the water until they are dissolved, add the gum-arabic, and withdraw from the fire. When the solution has become cold, complete 25 oz. with water and add Venetian red enough to bring it to a suitable consistency and colour. This ink must be preserved in a glass or earthenware vessel.

Printing Ink. Black (j). From Spent Cotton Waste. - The utilisation of waste products, which has made such great progress -during the last two decades, has experienced a further development in a department in which we are more especially interested. We refer to the process of C. T. Bastand, 38, Riley Street, Bermondsey, London, by means of which spent cotton waste is made to yield up all the oil and greasy matter contained in it, the latter being subsequently converted into that useful agent of civilisation, printers' ink. Cotton waste, as our readers are aware, is used to clean machinery of all descriptions. When spent - that is to say, used up - it is full of refuse oil and grease. Hitherto, it has been the practice to boil the spent cotton waste in a solution of caustic soda, by which process all the grease is extracted, to wash it, and mix it with new waste, when it is again placed upon the market. The oils and grease are allowed to run to waste.

Bastand proceeds in a very different and at the same time highly remunerative manner. He places the spent cotton waste in a closed cylinder heated by steam by means of an interior coil. He then pumps a solution of bisulphide of carbon into the cylinder containing the waste, upon which the chemical acts, separating the oil and grease. In their combined state, the bisulphide solution and oil are then run by him into another steam-heated cylinder. Here the bisulphide becomes vaporised, and passes thence to condensers, and is finally run into a store tank, to be used over and over again, the loss of bisulphide being almost imperceptible. The cotton waste freed from oil is washed, dried, and sold again.

The far more valuable product obtained, the oil, is run from the second cylinder into tanks, pumped thence into a copper heated by a small portable furnace, running on wheels, and freed from all moisture. It is then pumped into a second copper, where it is converted into the varnish from which printing ink is made. When the varnish has been brought down to its proper consistency, the furnace is withdrawn, and the varnish is taken to the mixing-house, where it is incorporated with the necessary pigments and other ingredients necessary to produce the various shades and qualities of printing ink. When mixed, the crude ink is ground in a French buhrstone mill, and, after grinding, delivered into a machine, in which it is passed between rollers a number of times, according to the quality of ink required. To obtain the lampblack used in the manufacture of printing ink, a portion of the recovered oil is used; and thus what was formerly wasted is converted into the medium which enters so largely into the diffusion of knowledge. (Chambers's Jl.)

Stamping Ink (A). Indelible. - E. Johanson, St. Petersburg, gives the formula for a convenient ink for marking clothing by means of a stamp: 22 parts carbonate of soda are dissolved in 85 parts glycerine, and triturated with 20 parts gum-arabic. In a small flask are dissolved 11 parts nitrate of silver in 20 parts officinal water of ammonia. The two solutions are then mixed and heated to boiling. After the liquid has acquired a dark colour, 10 parts Venetian turpentine are stirred into it. The quantity of glycerine may be varied to suit the size of the letters. After stamping, expose to the sun or apply a hot iron. (Pharm. Rec.)

(I) Polygraphic

(1) 10 parts "Violet de Paris," 30 parts water (Lebaigue). (2) 1 part "Violet de Paris," 7 parts water, 1 part alcohol (Kwaysser and Husak). (3) 2 parts acetate of rosaniline, 10 parts water, 1 part alcohol (Kwaysser and Husak).

The first two produce a violet, the last a red copy.

(k) An endorsing ink, which does not dry quickly on the pad, and is quickly taken by the paper, can be obtained by the following recipe: Anilin colour in solid form (blue, red, &c), 16 parts; 80 parts boiling distilled water, 7 parts glycerine, and 3 parts syrup. The colour is dissolved in hot water, and the other ingredients are added whilst agitating. This endorsing ink is said to obtain its good quality by the addition of the syrup. (Pap. Zeit.)