A very useful article for labeling bottles containing substances which would destroy ordinary labels consists of a mixture of ammonium fluoride, barium sulphate and sulphuric acid, the proportions for its manufacture being: barium sulphate, 3 parts; ammonium fluoride, 1 part; and sulphuric acid enough to decompose the fluoride and make a mixture of semi-fluid consistency. This mixture, when brought in contact with a glass surface with a common pen, at once etches a rough surface on the parts it comes in contact with. The philosophy of the action is the decomposition of the ammonium fluoride by the acid, which attacks the glass; the barium sulphate is inert, and is simply used to prevent the spreading of the markings. The mixture must be kept in bottles coated on the inside with paraffine or wax.
How to Remove Aniline Ink from the Hands.
Aniline inks are now in common use, especially in connection with the various gelatine tablets for multiplying copies of written matter. Upon the hands it makes annoying stains, difficult of removal by water or acids. They may be easily washed out by using a mixture of alcohol 3 parts, and glycerine 1 part.
An Ink which Cannot be Erased.
An ink which cannot be erased from paper or parchment by any known chemical solvent, and will retain its original color indefinitely, and last as long as the material on which it is written, is made as follows:—Make a solution of shellac in borax, to which add sufficient lampblack to give the requisite depth of color.
To Make Black Ink.
Lactate of iron, 15 grains; powdered gum arabic, 75 grains; powdered sugar, half a drachm; gallic acid, 9 grains; hot water, 3 ounces. (Lactate of iron is a novelty in ink-making, and the above formula may possibly suit those who have a taste for writing with mucilaginous matters instead of limpid solutions.)
Black Ink for Stencils.
The following is commended for the preparation of a black ink or paste for use with stencils:—Boneblack, 1 lb.; molasses, 8 ozs.; sulphuric acid, 4 ozs.; dextrine, 2 ozs.; water sufficient. Mix the acid with about two ounces of water, and add it to the other ingredients, previously mixed together. When the effervescence has subsided, enough water is to be added to form a paste of convenient consistence.