A knowledge of this ancient and popular belief in Sideral influence, will enable us to explain many superstitions in Physic; the custom, for instance, of administering cathartic medicines at stated periods and seasons, originated in an impression of their being more active at particular stages of the moon, or at certain conjunctions of the planets: a remnant of this superstition still exists to a considerable extent in Germany; and the practice of bleeding at ‘spring and fall,’ so long observed in this country, owed its existence to a similar belief. It was in consequence of the same superstition, that the metals were first distinguished by the names and signs of the planets; and as the latter were supposed to hold dominion over time, so were astrologers led to believe that some, more than others, had an influence on certain days of the week; and, moreover, that they could impart to the corresponding metals considerable efficacy upon the particular days which were devoted to them;[24] from the same belief, some bodies were only prepared on certain days in the year; the celebrated earth of Lemnos was, as Galen describes, periodically dug with great ceremony, and it continued for many ages to be highly esteemed for its virtues; even at this day, the pit in which the clay is found is annually opened, with solemn rites by the priests, on the sixth day of August, six hours after sun rising, when a quantity is taken out, washed, dried, and then sealed with the Grand Signior’s seal, and sent to Constantinople. Formerly it was death to open the pit, or to seal the earth, on any other day in the year. In the botanical history of the middle ages, as more especially developed in Macer’s Herbal, there was not a plant of medicinal use, that was not placed under the dominion of some planet, and must neither be gathered nor applied but with observances that savoured of the most absurd superstition, and which we find were preserved as late as the seventeenth century, by the astrological herbalists, Turner, Culpepper, and Lovel. It is not the least extraordinary feature in the history of medical superstition, that it should so frequently involve in its trammels persons who, on every other occasion, would resent with indignation any attempt to talk them out of their reason, and still more so, to persuade them out of their senses; and yet we have continual proofs of its extensive influence over powerful and cultivated minds; in ancient times we may adduce the wise Cicero, and the no less philosophical Aurelius, while in modern days we need only recall to our recollection the number of persons of superior rank and intelligence, who were actually persuaded to submit to the magnetising operations of Miss Prescott, and some of them were even induced to believe that a beneficial influence had been produced by the spells of this modern Circe.