From the favourite locality of these legends we may infer that the magic then in vogue was that of the Arabs, which, especially in Spain, had now begun to supplant the ancient and primitive European superstitions. This magic was not a mere ritual of spells, such as that of the Chaldean monuments, but rather a complete theurgy, like the magic of Egypt; the corruption of an ancient and elaborate religious system.[259] The Arabian mage pretended to bow the superior powers which other men could only worship, and boldly bade them do his will. It is hardly necessary to say that such a system did not originally belong to the Arabs, who had been, until the days of Mohammed, a rude and savage people. They learned it in Syria and Egypt, where the theories of Porphyry and Iamblichus still held sway.[260] In their hands this magic became enriched with many new conceits, such as the nimble fancy of these children of the East knew well how to interweave with all that they touched. The stars, they held, were the centres of supreme influence, but had certain correspondences with earthly things; with herbs, with stones, and even with sounds. These were in a sort the offspring of heaven, for plants of power were precious things put forth by the sun and moon; the minerals were condensed and congealed by the same heavenly agency in a planetary hour, and earthly voices, even the cries of dumb animals, were but the far echo of the music heard in heaven, the music of the spheres. So far, indeed, this was but common doctrine, shared by all the science of the time, and eminently expounded in every astrological system. The magic founded upon it began with the notion that this close correspondence between heaven and earth might carry an influence able to react in an upward, contrary, and unnatural direction. Plants and precious stones, rightly employed, might prove able to bind the stellar powers on which all depended. Names and forms of conjuration might control the superior spirits which the stars represented. Hence arose a whole system of magical practice, in which, from the circle of the sorcerer—a symbol representing on earth the motion of the upper spheres—the vapour of mingled herbs and minerals rose to heaven above the glowing brazier, accompanied by recited spells. It is curious to notice that when, after several ages, this essentially Eastern and theurgic necromancy[261] gave place to the witchcraft of the North, with its dark demonolatry, the essential idea of the Arabian magicians still survived. Its influence may be traced in the importance always attached in popular belief to the _reversal_ of natural practice, as a means of securing supernatural power and effect. Hence the bizarre details which crowd the witch trials of the sixteenth and seventeenth centuries: how hags walked backwards, or _withershins_, that is, against the course of the sun, or changed a prayer into a spell by muttering it in a contrary sense.