Astrology also modified theology, by introducing into this pantheon a great number of new gods, some of whom were singularly abstract. Thereafter man worshiped the constellations of the firmament, particularly the twelve signs of the zodiac, every one of which had its mythologic legend; the sky (_Caelus_) itself, because it was considered the first cause, and was sometimes confused with the supreme being; the four elements, the antithesis and perpetual transmutations of which produced all tangible phenomena, and which were often symbolized by a group of animals ready to devour each other;[34] finally, time and its subdivisions.[35] The calendars were religious before they were secular; their purpose was not, primarily, to record fleeting {176} time, but to observe the recurrence of propitious or inauspicious dates separated by periodic intervals. It is a matter of experience that the return of certain moments is associated with the appearance of certain phenomena; they have, therefore, a special efficacy, and are endowed with a sacred character. By determining periods with mathematical exactness, astrology continued to see in them "a divine power,"[36] to use Zeno's term. Time, that regulates the course of the stars and the transubstantiation of the elements, was conceived of as the master of the gods and the primordial principle, and was likened to destiny. Each part of its infinite duration brought with it some propitious or evil movement of the sky that was anxiously observed, and transformed the ever modified universe. The centuries, the years and the seasons, placed into relation with the four winds and the four cardinal points, the twelve months connected with the zodiac, the day and the night, the twelve hours, all were personified and deified, as the authors of every change in the universe. The allegorical figures contrived for these abstractions by astrological paganism did not even perish with it.[37] The symbolism it had disseminated outlived it, and until the Middle Ages these pictures of fallen gods were reproduced indefinitely in sculpture, mosaics, and in Christian miniatures.[38]