The magi, the wise men, the seers, the astrologers of the ages gone by found much in the matter of gems that we have nearly come to forgetting. With them each gem possessed certain planetary attractions peculiar to itself, certain affinities with the various virtues, and a zodiacal concordance with the seasons of the year. Moreover, these early sages were firm believers in the influence of gems in one’s nativity,—that the evil in the world could be kept from contaminating a child properly protected by wearing the appropriate talismanic, natal, and zodiacal gems. Indeed, folklorists are wont to wonder whether the custom of wearing gems in jewelry did not originate in the talismanic idea instead of in the idea of mere additional adornment. The influence exerted by precious stones was assumed in medieval times without question, but when the spirit of investigation was aroused in the Renaissance period, an effort was made to find a reason of some sort for the traditional beliefs. Strange as it may seem to us, there was little disposition to doubt that the influence existed; this was taken for granted, and all the mental effort expended was devoted to finding some plausible explanation as to how precious stones became endowed with their strange and mystic virtues, and how these virtues acted in modifying the character, health, or fortunes of the wearer. When the existence of miracles is acknowledged, there will always be a tendency to regard every singular and unaccountable happening as a miracle; that is to say, as something that occurs outside of, or in spite of, the laws of nature. We even observe this tendency at work in our own time. As regards visual impressions, for instance, if a child of lively imagination enters a half-lighted room and sees a bundle of clothes lying in a corner, the indistinct outline of this mass may be transformed to his mind into the form of a wild animal. The child does not really see an animal, but his fear has given a definite outline and character to the indefinite image printed on the retina.