Aphorism 268 | Organon of Medicine By Dr. Hahnemann
The other exotic plants, barks, seeds and roots that cannot be obtained in the fresh state the sensible practitioner will never take in the pulverized form on trust, but will first convince himself of their genuineness in their crude, entire state before making any employment of them.1
1 In order to preserve them in the form of powder, a precaution is requisite that has hitherto been usually neglected by druggists, and hence powders, even of well-dried animal and vegetable substances could not be preserved uninjured even in well-corked bottles. The entire crude vegetable substances, though perfectly dry, yet contain, as an indispensable condition of the cohesion of their texture, a certain quantity of moisture, which dose not indeed prevent the unpulverized drug from remaining in as dry a state as is requisite to preserve it from corruption, but which is quite too much for the finely pulverized state. The animal or vegetable substance which in its entire state was perfectly dry, furnishes, therefore, when finely pulverized, a somewhat moist powder, which without rapidly becoming spoilt and mouldy, can yet not be preserved in corked bottles if not previously freed from this superfluous moisture. This is the best effected by spreading out the powder in a flat tin saucer with a raised edge, which floats in a vessel full of boiling water (i.e. a water-bath), and, by means of stirring it about, drying it to such a degree that all the small atoms of it (no longer stick together in lumps, but) like dry, fine sand, are easily separated from each other, and are readily converted into dust. In this dry state the fine powders may be kept forever uninjured in well-corked and sealed bottles, in all their original complete medicinal power, without ever being injured by mites or mould; and they are best preserved when the bottles are kept protected from the daylight (in covered boxes, chests, cases). If not shut up in air-tight vessels, and not preserved from the access of the light of the sun and day, all animal and vegetable substances in time gradually lose their medicinal power more and more, even in the entire state, but still more in the form of powder.
-Dr. Samuel Hahnemann