Homoeopathy makes use of all materials which are capable of modifying the health of living creatures, and hence collects its remedies from all the three kingdoms of nature. The following are considered the acknowledged methods of securing the best and most reliable preparations: -

1. As far as possible, collect all vegetable and animal products fresh.

2. Where they are the produce of foreign countries and can be only had as imported, obtain them from trustworthy druggists, but always in the state in which they were imported - never in the form of powder.

(This precaution is necessary, since druggists never hesitate to use the same mill for grinding different medicines - a laxity which would be unpardonable in a homoeopathic chemist.)

3. As regards plants, the time for collecting these must be regulated by the part which is officinal. Vegetable physiology must be here the guide, since it will enable us to predicate the exact time when the part will display most fully its characteristic properties. A few exceptions may exist to the following conclusions, but, as a general rule, it will be found that -

When the whole plant is used, it should be gathered when it is partly in flower and partly in seed.

When the leaves are used, they should be collected just before or during the early part of the flowering time.

This rule requires modification in the case of biennials, since the leaves which first appear in the spring of the second year are in this case the best, and should be collected as soon as the flowering stem begins to shoot.

When the flowers are used, they should be collected partly in bud and partly expanded.

When the seeds and fruits are the officinal part, they should be collected when fully ripe, unless otherwise ordered.

When the young shoots are ordered, they should be collected in spring, when the whole plant is in full vigour.

When the bark is employed, it must be collected either in the early spring or the autumn, most frequently at the latter season. The same rule holds good with respect to the root bark.

When the wood is the officinal part, it should be collected late in the autumn - in fact, after the fall of the leaf, if the tree is deciduous.

When the root is the part employed, it may be collected either late in the autumn or early in spring, but never when the aerial parts of the plant are in full activity.

4. After the fresh materials are collected they should be prepared as soon as possible, for the purpose of avoiding all deterioration. If gathered at some distance from home, the fresh plants should be packed carefully in tin cases (ordinary botanical boxes) and kept as cool as possible. If, however, there be no opportunity for preparing them for some time after their collection, they must be carefully dried by tying them in loose bundles and hanging them in the shade, protected from rain, etc, and as soon as they are dry they should be carefully packed in hermetically-sealed tin cases.

5. The same rules, as far as they apply, must be followed in the collecting of animal substances.

6. All minerals and chemical compounds must be carefully tested before they are used.

7. From the time that the medicinal substances are obtained until they are converted into the regular pharmaceutical preparations, they should be most carefully preserved from damp and dust, from contact with other medicinal materials, from strong odours of any kind, and from light. All should be preserved in glass or earthenware jars or bottles, and be well corked or stoppered.

It will now be necessary to give in detail the directions for making the different preparations.