The third book, after a short and offensively allusive description of the labours of preceding poets, sketches the twelve _athla_ or accidents of human life, to each of which is assigned its special guardian influence. It then passes to the horoscope, which it treats at length, giving minute and various directions how to draw it. The extreme importance attached to this process by Tiberius, and the growing frequency with which, on every occasion, Chaldeans and Astrologers were now consulted, made the poet specially careful to treat this subject with clearness and precision. It is accordingly the most readable of all the purely technical parts of the work. The account of the tropics, with which the book closes, is singularly inaccurate, but contains some rather elegant descriptions: [81] at the tropic of Cancer summer always reigns, at Capricorn there is perpetual winter. The book here breaks off quite abruptly; apparently he intended to compose the epilogue at some future time, but had no opportunity of doing it. The exordium to the fourth book, which sometimes rises into eloquence, glorifies fate as the ultimate divine power, but denies it either will or personality. He fortifies his argument, according to his wont, by a historical catalogue, which exemplifies the harshness that, except in philosophical digressions, rarely leaves his style. Then follow the horoscopic properties of the Zodiacal constellations, the various reasons for desiring to be born under one star rather than another, a sort of horoscopico-zodiacal account of the world, its physical geography, and the properties of the zones. These give occasion for some graphic touches of history and legend; the diction of this book is far superior to that of the preceding three, but the wisdom is questionable which reserves the "good wine" until so late. Passing on to the ecliptic, he drags in the legends of Deucalion, Phaethon, and others, which he treats in a rhetorical way, and concludes the book with an appeal to man's reason, and to the necessity of allowing the mental eye free vision. Somewhat inconsistently with the half-religious attitude of the first and second books, he here preaches once more the doctrine of irresistible fate, which to most of the Roman poets occupies the place of God. The poem practically ends here. He himself implies at the opening of Book V., that most poets would not have pursued the theme further; apparently he is led on by his interest in the subject, or by the barrenness of his invention which could suggest no other. The book, which is unfinished, contains a description of various stars, with legends interspersed in which a more ambitious style appears, and a taste which, though rhetorical and pedantic, is more chastened than in the earlier books.