It is probable that the pallor of the patient's hands as the background to the stone made the difference in its appearance thus noted. It became deeper in hue, as it were, when people were in ruddy health. The suggestive influence of such beliefs is easy to understand. It is even possible that the wearing of an amethyst did help to keep people from indulging in liquor to excess, for that is the traditional effect of the wearing of this stone, though its virtue seems to be founded on nothing better than the supposed derivation of the name from the Greek _a_ privative and _methuo_, "I get drunk," suggesting strongly to the wearer that he should not get drunk. The jacinth superinduced sleep and doubtless the strong suggestion of this supposed influence helped many sufferers from so-called insomnia to get sleep. The single fixed idea that now they must get to sleep would greatly help them. Pillows in the olden time were occasionally set with bits of jacinth, and there is even the record of bed-linen embroidered with it. This would probably be quite as effective as are hop-pillows in the modern time, for their main influence, as is also true of pine pillows, seems to be through suggestion. Some other traditions with regard to precious stones are harder to understand, yet may be explained. The owner of a diamond was supposed to be invincible. Diamonds represented money and money meant power. It is harder to explain the tradition that the possession of an agate made a man able and eloquent. The wide acceptance of the doctrine of signatures, and of allied ideas, as to the effect of precious stones and metal and jewelry upon disease, makes {38} it clear that the acceptance of a mental persuasion with the changes in habits that follow, may serve as the basis of a successful system of therapeutics. The materials associated with the idea had absolutely no more physical influence than does the carrying of a horse chestnut or a potato in the pocket serve to keep off rheumatism. CHAPTER V PSEUDO-SCIENCE AND MENTAL HEALING