It has been truly said, that “Ptolemy’s order, false as it was, enabled observers to give a plausible account of the motions of the Sun and Moon, to foretell eclipses, and to improve geography[10];” or, in other words, that it represented the actual phenomena of the heavens as they really appear to a spectator on the earth. It is therefore clear that Ptolemy’s astrology is just as applicable to modern and improved astronomy as it was to his own.[11]
In the year 827[12] the “Great Construction” was translated by the Arabians into their own language, and by them communicated to Europe. It is through them that it has been usually known by the name of the Almagest. In the 13th century, the Emperor Frederic II caused it to be translated from the Arabic into Latin, and Sacrobosco[13] was consequently enabled to write his famous work upon the sphere. It was not, however, until about the end of the 15th century that the “Great Construction” was translated into Latin from the original text; and this important service was rendered to science by Purbach, a professor of philosophy at Vienna, who learned the Greek tongue at the instigation of Cardinal Bessarion. By means of this translation, the Ephemerides of George Müller, surnamed Regiomontanus, a disciple of Purbach’s, were first composed. The Greek text of the Almagest, or Great Construction, was first published at Basle, by Simon Grynæus, in 1538; and it was again printed at the same place in 1551, with certain other works of Ptolemy.[14] The rest of Ptolemy’s works connected with astronomy, and now extant, are the Tetrabiblos, or Four Books of the Influence of the Stars[15] (now translated); the Centiloquy, or Fruit of his Four Books, being a kind of supplement to the former; and the Significations of the Fixed Stars. The last is merely a daily calendar, showing the risings and settings of the stars, and the nature of the weather thereby produced. There are likewise extant his geographical work (which has rendered important service to modern geographers), and also his celebrated book on Harmonics, or the Theory of Sound.
Proclus, to whom the world is indebted for the improved text of the Tetrabiblos,[16] was born at Constantinople, in the year 410. He studied at Alexandria and at Athens, and became very eminent among the later Platonists. He succeeded Syrianus, a celebrated philosopher, in the rectorship of the Platonic school at Athens, and died there in 485.[17] He was a most voluminous author, in poetry as well as in prose. Among his works there are Hymns to the Sun, to Venus, and to the Muses; Commentaries upon several pieces of Plato, and upon Ptolemy’s Tetrabiblos[18]; an Epitome or Commendium of all the Astronomical Precepts demonstrated in the Almagest; and elements of Theology and Natural Philosophy. He was in dispute with the Christians on the question of the eternity of the world, which he undertook to prove in eighteen elaborate arguments. A late writer in a certain periodical work has erroneously identified him with another Proclus, who was in favour with the Emperor Anastasius, and who destroyed the ships of Vitalianus, when besieging Constantinople in 514, by burning them with great brazen mirrors, or specula.
Signs of the Zodiac.
| ♈ | Aries | ♎ | Libra |
| ♉ | Taurus | ♏ | Scorpio |
| ♊ | Gemini | ♐ | Sagittarius |
| ♋ | Cancer | ♑ | Capricorn |
| ♌ | Leo | ♒ | Aquarius |
| ♍ | Virgo | ♓ | Pisces |
PTOLEMY’S TETRABIBLOS
OR
FOUR BOOKS
OF THE
INFLUENCE OF THE STARS