But to return from our digression--any one may see how such an observation of the stars furnished a second mode of ascertaining the length of the year. The men of the olden time were driven to this earnest watching of the heavens by an interest, of which, in these days of almanacs, and clocks, and compasses we can form but an inadequate conception. The period of the year was named after the principal star that rose just before, or set just after the sun. For example, when Sirius rose and set with or near the time of the sun, it was called the "dog days"--the only one of these old sidereal measures of time that has come down to us. Another season was under the sway of Orion. It was called the "stormy constellation," and at its heliacal rising, or when, as Hesiod expresses it, The gentle Pleiads, shunning his fierce pursuit, Sank late in the Ocean wave-- then was the ship to be drawn up into the well-secured harbor, and the sailor for a season to shun the dangerous deep. In the same way the periods of different agricultural operations were assigned to different constellations--some to Arcturus, others to the humid Hyades, and others, again, to the Bull, who "opened the year with his golden horns." From the observed fact of simultaneousness arose, also, the notion of some secret causative influence between the concurrent events. Hence those views of astrology, so early and so widely held among mankind, and which assigned to each event its celestial concomitants, and to each individual man his natal star. Exploded it may have been by the modern progress, but there was nevertheless at bottom an _idea_ of more value than any science, however accurate, that does not give it the first and highest place. It was the thought of the absolute unity of nature, and of the unbroken relation of every part of the universe to every other part--in other words, the sublime idea which the oldest philosophy strove to express by that grand word, Kosmos. The length of the year, as a whole number, was early known. It was some time, however, before the disturbance created by the fraction began to be distinctly perceived, and still longer before it was reduced to any thing like satisfactory measurement. In the division of the 365 days into monthly periods, lay at first the greatest difficulty. The lunar number was in general employed, not only as the nearest marked divisor, but because the new and full moons were so generally connected with religious festivals whether this arose from convenience of arrangement, or from the idea of some deep religious meaning symbolized by the ever dying and reviving phases of this mysterious planet. We can not, however, help being struck with the superior accuracy of the Jewish, when compared with the confusion and change that prevailed in the Greek and Roman calendar.