Fasti | Page 3

the same. During a part of the year Orion flamed in full magnificence on the sky, and, to the eye of the Grecian herdsman and hunter, he and his Dog pursued the Bear, who kept watching him while the Pleiades (Peleiades, pigeons) were flying before him; at another season the sky was destitute of this brilliant scene. It was soon observed that the stars made 'their exits and their entrances' at regular periods, corresponding with the changes which took place in the course of nature on earth, and these coincidences were marked and employed for agricultural purposes. A people who have no regular scientific calendar, always contrives a natural one, taken from celestial or terrestrial appearances. Thus the North American Aborigines designate times and seasons by the flowering of certain plants; the ancient Greeks appear to have done something of the same kind, for one of Hesiod's designations of a particular season is, _when the thistle is in blossom_; we ourselves call the first season of the year the Spring, (i.e. of plants,) and our Transatlantic brethren term the autumn, the Fall (of the leaves).
The Greeks, however, seem early to have seen the superior accuracy and determinateness of the celestial phenomena. In the didactic poem of Hesiod, this mode of marking the times of navigation and of rural labours is frequently employed, and its use was retained by the countryfolk of both Greece and Italy far into the time of the Roman empire. Those who wrote on rural subjects or natural history, employed it; we meet it in Aristotle, as well as in Pliny and Columella.
When intercourse with Egypt and Phoenicia had called the thoughts of the Greeks to natural science, the rude astronomy of their rustic forefathers became the subject of improvement. The name of Thales is, as was to be expected, to be found at the head of the cultivators of this science. He is said to have been the first who taught to distinguish between the real and apparent rising and setting of a constellation; which implies a knowledge of spheric astronomy. His example was followed and observation extended by others, and as rain, wind, and other a?rial phenomena were held to be connected with the rising and setting of various signs, the times of their risings and settings, both apparent and real, were computed by Meton, Eudoxus, and other ancient astronomers. The tables thus constructed were cut on brass or marble, and fixed up (whence they were called [Greek: parapaegmata],) in the several cities of Greece, and the peasant or sailor had only to look on one of these _parapegmata_, to know what sign was about to rise or set, and what weather might be expected. Without considering the difference of latitude and longitude, the Romans borrowed the _parapegmata_, like every thing else, from the Greeks. The countrymen, as we learn from Pliny (xviii. 60, 65,), ceased to mark the stellar heaven, a _Kalendarium rusticum siderale_, (Colum. ix. 14) taught him when the signs rose and set, and on what days he was to expect sacrifices and festivals. When Virgil (G. I. 257.) says,
Nec frustra signorum obitus speculamur et ortus, Temporibusque parem diversia quattuor annum.
it is, (as Voss observes,) more probable that it is one of these calendars, and not the actual heaven that he means.
Before the time of Thales it was, of course only the visible and apparent risings and settings of the signs that were the subject of observation. But astronomers now learned to distinguish these phenomena into three kinds. These they termed the cosmic, acronych, and heliac risings and settings. The cosmic rising or setting ([Greek: kosmikos epitolae], or [Greek: dusis],) was the true one in the morning; the acronych ([Greek: akronychos][1]), _prima nox_, is evening, the beginning (one end) of the night, the true one in the evening; the heliac, ([Greek: haeliakos]) the apparent rising in the morning or setting in the evening. A star was said to rise or set cosmically, when it rose or set at sun-rise; it rose or set acronychally, when it rose or set at sun-set; it rose heliacally, when in the morning it just emerged from the solar rays, it set in the same manner, when in the evening it sank immediately after him. Two general observations may be made here. 1. In the morning the true rising precedes the apparent one, perhaps several days. 2. In the evening the apparent setting precedes the real one. To illustrate this. Let us suppose it 'spring time when the sun with Taurus rides,' the Hyades which are in the head of Taurus will rise with the sun, but lost in his effulgence they will elude our vision; at length when in his progress through the Tauric portion of the ecliptic, he has left them a sufficient distance behind