Many inks, especially those made with iron and galls, are liable to mould and decompose. The formation of mould may, to a certain extent, be prevented by the use of creosote, carbolic acid, or cloves, and most of the better class of inks in market are prepared so as to resist this evil.

In the recipes generally given for making ink, it is recommended to boil the ingredients. A much better plan is to powder the galls and macerate them in cold water. By this latter process, more time is of course necessary to make it; but then the ink is very superior, and entirely free from extractive matter which has no inky quality, and which only tends to clog the pen and to turn the ink ropy and mouldy.

Black Ink

1. In 1 gallon of water macerate 1 lb. of finely powdered Aleppo galls for two weeks, and strain off the liquid. Dissolve 5 1/2 oz. sulphate of iron and 5 oz. gum arabic in as little water as is necessary, and mix the two liquids with constant stirring. Keep in a tall bottle, allow it to settle for some days, and it will be ready for use.

2. Take gall nuts, broken, one pound; sulphate of iron, half a pound; gum acacia and sugar candy, of each, a quarter of a pound; water, three quarts. Place the whole of these ingredients in a vessel where they can be agitated once a day; after standing for a fortnight or three weeks the ink is ready for use. Logwood and similar materials, are often advised to be used in conjunction with the gall nuts, but they serve no good purpose xanless it be to make a cheaper article which fades rapidly.

3. It is said that the juice of elder erries to which sulphate of iron has been added, makes a good ink. The best formula is said to be 12 1/2 pints juice and 1/2 oz. each sulphate of iron and crude pyroligneous acid.

Runge's Black Ink

1. The original recipe of the inventor is as follows: Digest 1/4 lb. logwood in chips for 12 hours in 3 pints boiling water. Simmer down gently to 1 quart, filter and add 20 grains yellow chromate of potassa.

2. The following modification of the above is more easily prepared: Dissolve 16 parts of extract of logwood in 1,000 parts of water, and add 1 part of neutral potassium chromate (yellow chromate of potassa).

Blue Ink

Take 6 drachms pure Prussian blue and 1 drachm oxalic acid. Grind in a mortar with a little water until they form a perfectly smooth paste. Dissolve a sufficient quantity of this paste in water to give the proper tint.

Carmine Ink, French Process

Take 22 grammes (4 grains) of the best carmine, add to it sixty-five grammes (2 ounces} of caustic ammonia, add one gramme (15 1/2 grains) of white gum arabic. Leave the mixture until the gum is entirely dissolved. This ink is undoubtedly dearer than that prepared in the ordinary way, but it is incomparably more beautiful and more durable, for experience has proved that letters written with this ink, have for forty years been preserved without the slightest alteration.

Red Ink

Boil 1/2 lb. of Brazil wood, 1/4 oz. of gum, 1/2 oz. of sugar, and 1/2 oz. of alum in a sufficient quantity of vinegar.

Aniline Inks

The following formulae for aniline inks are from recent authorities, and are said to give superior results:

Alcoholic Solutions

1. General Formula: Dissolve 15 parts of aniline color in 150 parts of strong alcohol in a vessel of glass or enamelled iron for three hours; then add 1,000 parts distilled water; heat gently for some hours, - in fact, till the odor of the alcohol has quite disappeared; then add a solution consisting of 60 parts of powdered gum arabic in 250 parts of water.

2. Special Formula for Violet: Digest 1/2 oz. aniline violet in 1 oz. alcohol in a suitable vessel, as above, for three hours; then add 1 qt. of distilled water, and heat gently till odor of spirit is dissipated. Then add 2 drachms gum arabic dissolved in 1/2pt. water, and allow the whole to settle. This will bear dilution, if desired, with an additional quantity of distilled water.

3. Special Formula for Blue: Dissolve 15 grains aniline blue in 1 oz. alcohol, and add 6 oz. in distilled water. Boil in proper vessel, as above, until odor of alcohol has disappeared. Then add 3 drachms powdered gum arabic dissolved in 4 oz. distilled water. Finally filter. It will be perceived that there is considerable difference in the above special formulae, but there can be no harm in making it too strong, as it is no difficult matter to dilute with distilled water to taste.