General Rule

All substances soluble in either Alcohol or water, are properly made into solutions or tinctures; all insoluble or only partially soluble substances should first be made into triturations only.

Aqueous Solutions

Aqueous Solutions are made from such chemicals as are soluble in water. Hygroscopic substances, such as some of the potash and soda preparations ought to be so prepared in the lower potencies in preference to triturating them. The solutions are made in the proportion of one in ten, one in one hundred and one in one thousand, depending upon the degree of the solubility of the substance. Such solutions are as a rule unstable and do not keep for any length of time, and ought, therefore, be renewed whenever required. The solution must be clear, free from sediment and cloudiness.

Tinctures

Homoeopathic tinctures are made from plants and other substances wholly or partially soluble in Alcohol. They are, therefore, alcoholic solutions of solids or semi-solids. The chief source of homoeopathic tinctures is the fresh plant, but parts of plants, barks, roots, seeds, gums, balsams, etc., are also used. Minerals and chemicals soluble in alcohol also give tinctures. When made from plants, it is essential to obtain the fresh flowering plant, whenever possible, the dried article always being inferior, often inert. For this reason, homoeopathic tinctures must be imported from the country, where the plants, grow and in no case will it answer to substitute a tincture made from the dried plant, or worse still, from a fluid extract. It is very important that tinctures should be of uniform strength, and as the watery, proportion varies greatly according to season and other conditions, the dried, crude drug is taken as the starting point from whence to calculate the strength of the tincture. This is readily ascertained by taking a suitable quantity of the fresh plant and weighing it, then drying it by gentle heat until there is no further loss of weight. The difference of weight will indicate the amount of water contained in the plant for which allowance is to be made in the use of the menstrua. But remember, that while the dry, crude material after evaporation is taken as a unit of strength, the fresh green plant is to be used in the preparation of the tincture.

The tincture represents one part of this dry, crude material in each ten parts of the completed solution, i. e., lx would represent its drug power. This is the method prescribed by the British and American Institute pharmacopoeias, and leads to accurate and scientific results. At present, however, many tinctures are not made so and the mother tincture represents varying degrees of drug power, which ought to be known in each instance, in order to make an exact lx attenuation.

Dilutions Or Liquid Attenuations

Hahnemann introduced and adopted as the standard, a progressive scale of diluting drugs in the proportion of 1 to 99 known as the Centesimal Scale.

Under this rule each attenuation contains just 1/100 part as much of the drug substance as the preceding attenuation. The potencies so prepared are marked 1, 2, 3,4, etc., according to the potency represented. The first, 1, containing 1/100 part of the crude drug, the second, marked 2, the 1/100 part of the first, or 1/1000 of the orginal drug; the third, marked 3, the 1/100 of the second, or the 1/1000000 of the original, etc. Later, in order to secure intermediate grades of strength and better communication of the particles, Hering introduced the Decimal Scale, the proportion of 1 to 9 by which each successive dilution contains just 1/10 as much of the drug substance as the preceding one.

Decimal preparations are designated such by an x; thus the first decimal is marked lx, and contains 1/10 part of the original drug substance; the second decimal is marked 2x, and contains the 1/10 part of the first decimal, or 1/100 of the original drug-substance. Thus it will be seen that the first centesimal is equal to the 2x; the 2nd centesimal, marked 2, is equal to the 4th decimal; the 3d centesimal to the 6x, etc., etc.