CHAPTER IX. SCIENTIFIC KNOWLEDGE AMONG THE ROMANS.

And yet their researches were very unsatisfactory until the time of Hipparchus. The primitive knowledge, until Thales, was almost nothing. The Homeric poems regarded the earth as a circular plain, bounded by the heaven, which was a solid vault or hemisphere, with its concavity turned downwards. And this absurdity was believed until the time of Herodotus, five centuries after; nor was it exploded fully in the time of Aristotle. The sun, moon, and stars, were supposed to move upon, or with, the inner surface of the heavenly hemisphere, and the ocean was thought to gird the earth around as a great belt, into which the heavenly bodies sunk at their setting. [Footnote: Il., vii. 422; Od., iii. i. xix. 433.] Homer believed that the sun arose out of the ocean, ascending the heaven, and again plunging into the ocean, passing under the earth, and producing darkness. [Footnote: Il. viii. 485.] The Greeks even personified the sun as a divine charioteer driving his fiery steeds over the steep of heaven, until he bathed them at evening in the western waves. Apollo became the god of the sun, as Diana was the goddess of the moon. But the early Greek inquirers did not attempt to explain how the sun found his way from the west back again to the east. They merely took note of the diurnal course, the alternation of day and night, the number of the seasons, and their regular successions. They found the points of the compass by determining the recurrence of the equinoxes and solstices; but they had no conception of the ecliptic - of that great circle in the heaven, formed by the sun's annual course, and of its obliquity when compared with the equator. Like the Egyptians and Babylonians, they ascertained the length of the year to be three hundred and sixty-five days; but perfect accuracy was wanting for want of scientific instruments, and of recorded observations of the heavenly bodies. The Greeks had not even a common chronological era for the designation of years. Thus Herodotus informs us that the Trojan War preceded his time by eight hundred years: [Footnote: Il, ii. 53.] he merely states the interval between the event in question and his own time; he had certain data for distant periods. Thus the Greeks reckoned dates from the Trojan War, and the Romans from the building of their city. And they divided the year into twelve months, and introduced the intercalary circle of eight years, although the Romans disused it afterwards until the calendar was reformed by Julius Caesar. Thus there was no scientific astronomical knowledge worth mentioning among the primitive Greeks.

Immense research and learning have been expended by modern critics, to show the state of scientific astronomy among the Greeks. I am equally amazed at the amount of research, and its comparative worthlessness, for what addition to science can be made by an enumeration of the puerilities and errors of the Greeks, and how wasted and pedantic the learning which ransacks all antiquity to prove that the Greeks adopted this or that absurdity. [Transcriber's Note: Lengthy footnote relocated to chapter end.]

[Thales.]

[Anaximander and Anaximenes.]

But to return. The earliest historic name associated with astronomy in Greece was Thales, the founder of the Ionic school of philosophers, born 639 B.C. He is reported to have predicted an eclipse of the sun, to have made a visit to Egypt, to have fixed the year at three hundred and sixty-five days, and to have determined the course of the sun from solstice to solstice. He attributed an eclipse of the moon to the interposition of the earth between the sun and moon; and an eclipse of the sun to the interposition of the moon between the sun and earth. [Footnote: Sir G. G. Lewis, Hist. of Astron., p. 81.] He also determined the ratio of the sun's diameter to its apparent orbit. As he first solved the problem of inscribing a right-angled triangle in a circle, [Footnote: Diog. Laert, i. 24.] he is the founder of geometrical science in Greece. He left, however, nothing to writing, hence all accounts of him are confused. It is to be doubted whether in fact he made the discoveries attributed to him. His speculations, which science rejects, such as that water is the principle of all things, are irrelevant to a description of the progress of astronomy. That he was a great light, no one questions, considering the ignorance with which he was surrounded. Anaximander, who followed him in philosophy, held to puerile doctrines concerning the motions and nature of the stars, which it is useless to repeat. His addition to science, if he made any, was in treating the magnitudes and distances of the planets. He attempted to delineate the celestial sphere, and to measure time by a sun-dial. Anaximenes of Miletus taught, like his predecessors, crude notions of the sun and stars, and speculated on the nature of the moon, but did nothing to advance his science on true grounds, except the construction of sun-dials. The same may be said of Heraclitus, Xenophanes, Parmenides, Anaxagoras. They were great men, but they gave to the world mere speculations, some of which are very puerile. They all held to the idea that the heavenly bodies revolved around the earth, and that the earth was a plain. But they explained eclipses, and supposed that the moon derived its light from the sun. Some of them knew the difference between the planets and the fixed stars. Anaxagoras scouted the notion that the sun was a god, and supposed it to be a mass of ignited stone, for which he was called an atheist.

[Socrates.]

[Pythagoras.]