A distinction is often made between the talismanic qualities of precious stones for the cure or prevention of disease and the properly medicinal use of them as mineral substances. In the former case the effect was attained by merely wearing them on the person, while in the latter case they were reduced to a powder, which was dissolved as far as possible in water or some other liquid and then taken internally. As, however, the end to be attained is the same whether the stone be worn or taken internally as a powder or liquid, it seems more logical to treat of both these methods of therapeutic use together, reserving for the chapter on the talismanic use of gems only their employment to avert misfortunes other than those caused by disease, and their influence in the procuring of wealth, honors, and happiness for their wearers. The belief in the curative properties of precious stones was at one time universal among all those to whom gems were known. When we read to-day of the various ills that were supposed to be cured by the use of these gems, we find it difficult to understand what process of thought could have suggested the idea of employing such ineffectual remedies. It is true that the constituents of certain stones can be absorbed by the human body and have a definite effect upon it, but the greater part of the elements are so combined that they cannot be assimilated, and they pass through the system without producing any apparent effect. In ancient and medieval times, however, other than chemical agencies were supposed to be efficient in the cure of diseases, and the primitive animistic conception of the cause of illness, and hence of the therapeutics of disease, long held sway among those who practised the medical art. Remedies were prized because of their rarity, and also because it was believed that certain spiritual or planetary influences had aided in their production and were latent in them. Besides this, the symbolism of color played a very important part in recommending the use of particular stones for special diseases. This may be noted in the case of the red or reddish stones, such as the ruby, spinel, garnet, carnelian, bloodstone, etc. These were thought to be sovereign remedies for hemorrhages of all kinds, as well as for all inflammatory diseases; they were also believed to exercise a calming influence and to remove anger and discord. The red hue of these stones was supposed to indicate their fitness for such use, upon the principle _similia similibus curantur_. In the same way yellow stones were prescribed for the cure of bilious disorders, for jaundice in all its forms and for other diseases of the liver.