Page:The American Cyclopædia (1879) Volume II.djvu/55

 ASTRONOMY 43 first gradually displaced astrology for the ben- efit of true scientific knowledge. Astrology was early developed in Egypt, but chiefly flourished in Chaldea, whose " star-gazers and monthly prognosticators " weVe so famous that the name Ohaldee came to be used as identical with astrologer, not only in the Scriptures, but also by the classical writers. In the East it still has its votaries. It was much practised in im- perial Rome. It was forbidden by Augustus, and the edict was often reenacted by later em- perors, but was apparently not much regarded. The Arabs revived astrology with astronomy. The Moors in Spain held it in great respect, and by their influence it was made popular among the Gothic nations of western Europe. The astronomical tables of Alfonso X. in the 13th century were in great part intended for astrological purposes. Astrology continued to increase in credit till the middle of the 16th century, was still practised at European courts at the end of the 17th, and had a few votaries' till the end of the 18th, even in England. It was in high repute at the court of Catharine de' Medici ; it was considered a science even by Kepler ; and Lilly, the last of the famous as- trologers, was called before a committee of the house of commons in the reign of Charles II. to give his opinion of future events. The gen- eral method of procedure in finding the fate of any man or enterprise was to draw a horo- scope, representing the position of the stars and planets, either in the whole heaven, or within one degree above the eastern horizon, at the time of birth of the individual or the in- ception of the undertaking. Arbitrary signifi- cations were given to different heavenly bodies, as they appeared singly or in conjunction ; and according to these significations, the horoscope was interpreted. The presence of Venus fore- told love; Mars, war; Jupiter, power; the Pleiades, storms at sea, &c. The system of a reputable astrologer in the 16th century re- quired years for its mastery ; and absurd as its fundamental principles now appear, its details were not inconsistent with each other, and the whole system has a completeness which ap- pears very singular in a scheme so visionary. ASTRONOMY (Gr. aarpov, a star, and v<i//oc, law), the science which deals with the move- ments, distribution, and physical character- istics of the heavenly bodies. That astronomy is the most ancient of all the sciences, save agriculture, can scarcely be questioned. In the earliest ages men must have required measures of time, and such measures could only be ob- tained from the study of the motions and ap- pearances of the celestial bodies. The origin of astronomy has been referred to several nations. The evidence in favor of the Chal- deans seems on the whole the strongest. We find in Ptolemy's Almagest the records of ob- servations of considerable accuracy made at Babylon at a very early epoch. Some of the observations which were transmitted to Aris- totle by Callisthenes were made about 2250 years B. C. The Chaldean investigations of the motions of the moon were in many respects remarkable. In particular their invention of the saros indicates not merely very accurate observation and a careful discussion of the re- sults, but considerable ingenuity. They were also acquainted with the art of dialling; they had discovered the precession of the equinoxes, and had determined the length of the tropical year to within less than half a minute of its true value. There are even reasons for believ- ing that they were acquainted with the true system of the universe ; and we learn from Diodorus Siculus and Apollonius Myndius that the Chaldean astronomers regarded comets as bodies travelling in extended orbits, and even in some instances predicted the return of these objects. Indian astronomy does not appear to have been by any means so accurate as that taught by the Chaldeans. The Indian system seems indeed to have belonged to a more northerly latitude than Benares, the chief seat of Hindoo learning. Accordingly M. Bailly was led to ascribe the origin of the system to a nation which had inhabited higher latitudes; and he even went so far as to invent a nation for the occasion, the Atlantides, and to ascribe to that apocryphal nation a wholly incredible degree of learning. It may be inferred that the want of agreement between celestial phenom- ena in India and the Indian system of astron- omy, instead of justifying M. Bailly's argument, shows rather that the Indian astronomers were but imperfectly acquainted with the phe- nomena of the heavens. Nor is it easy to ac- cept the opinion of Prof. Smyth, astronomer royal for Scotland, that the ancient Egyptians, the architects of the great pyramid, were ac- quainted with all the facts which he conceives to have been symbolized in that remarkable edifice. That the pyramid was erected for astronomical purposes may be admitted; and we may accept Prof. Smyth's conclusion that the building of the pyramid corresponded to the time when the star a Draconis at its upper transit was visible (as well by day as by night) through the long inclined passage which forms one of the characteristic features of the pyra- mid. This would set the epoch about the year 2170 B. C. And it is a remarkable fact that, as Prof. Smyth points out, the Pleiades were at that time in a most peculiar position, well worthy of being monumentally commemorated ; " for they were actually at the commencing point of all right ascensions, or at the very be- ginning of running that great round of stellar chronological mensuration which takes 25,868 years to return into itself again, and has been called elsewhere, for reasons derived from far other studies than anything hitherto con- nected with the great pyramid, the 'great year of the Pleiades.' " But although we may thus set the astronomical system of the early Egyptians in a far antiquity, it seems unsafe to follow Smyth in believing that the builders of the great pyramid were acquainted with