Note 131 — MEMOIRS OF THE LIFE OF DAVID RITTENHOUSE; ANTERIOR TO HIS SETTLEMENT IN PHILADELPHIA.

See Martin’s Philosophia Britannica, lect. xi. note 141. Though “Orrery” be a modern name, the invention of such machines as it is now applied to, is of a very early date. The first planetarium or orrery, of which we have any account, was the famous machine of Archimedes. This consisted, as Cicero (in his Tusculan Questions) asserts, of a sphere, of an hollow globular surface, of glass, within which was some ingenious mechanism, to exhibit the motions of the moon, the sun, and all the planets then known. Very imperfect as it must necessarily have been in other respects, it was radically erroneous, in being adapted to the Ptolomaic system. This is described in Latin verse, by the poet Claudius Claudianus, of Alexandria, who flourished about four centuries after the Christian era, and more than six centuries after the Syracusean philosopher.

Cicero, in his book De Naturâ Deorum, mentions one invented by Posidonius the Stoic, in his time, and about eighty years before the birth of Christ. He describes it as a “sphere,”—“in every revolution of which, the motions of the sun, moon, and five planets were the same as in the heavens, each day and night.”

Nothing further is heard of orreries or spheres, until about five hundred and ten years after Christ, when Anicius Manlius Torquatus Severinus Bœthius, the Roman Consul, (who was also a Christian, and a Peripatetic Philosopher,) is said to have contrived one. Theodoric, king of the Goths, calls it “Machinam Mundo gravidam, Cœlum gestabile, Rerum Compendium”: But Bœthius was, nevertheless, put to death by this Gothic king, A. D. 524. A long and dismal reign of barbarism and ignorance having succeeded this period, no further mention is made of any thing in the nature of a planetarium, for about one thousand years. See Note 95.