The Conftit, and Parts of the Universe. 105 B. The fixed Stars, which enamel and bespangle the concave Expanfe, or Canopy of Heaven; which by their Numbers and Luftre, make the Night beauteous and delightful, which would be otherwise dark and horrible: And thus I have rehearsed to you all the great Parts of which the World doth confift, fo far as we know any Thing of it. A. Pray what is the Form or Figure of the Universe? B. It hath no determinate Form or Figure at all; forafmuch as it is every way infinite and unlimited. A. Pray what do you call the mundane Space? B. The infinite Space, in which all Bodies of the Universe have their Place and Being. A. Pray what do you properly call Space? B. Extenfion without Matter; or, in plain English, a perfect Void, or Vacuity; which is better conceived than defined. A. What is that the Philofophers call a Vacuum ? or B. A Vacuum is a perfect Void, Space abfolutely devoid of all Body or Matter; as on the contrary, they call that a Plenum, when any Part of Space is fo abfolutely filled with Matter, as to have no Vacuities therein. A. Is A. Is there any fuch Thing as a Vacuum in Nature, I pray? B. Yes; only thofe who have denied their Reafon, have denied this; or else have been fuch miferable poor Philofophers as not to know what Vacuum, or Na ture meant. A. How do you prove a Vacuum? B. A thousand Ways almoft; but Motion evinceth it moft plainly, for can any one fuppofe a Body to move in the midst of Solidity? They who affirm this, may as rationally affirm that a Bird may fly through a Mountain of Adamant, as easily as through the open Air: And who fo blind as not to fee the most monftrous Abfurdity thereof by this one Argument? A. I think none can deny it indeed, who would be thought rational: But, pray, what have you to fay of Duration or Time? B. Duration is the Idea we have of the Continuance of the Existence, or Being of Things; and in order to estimate or meafure the Parts thereof, we use the Motions of moving Bodies, as the Sun, Stars, a Clock, &c. and the Parts of Duration thus compared and measured, we call Time, Times, Seafons, Ages, &c. C CHAP. A. [ 107 ] CHA P. II. Of Uranology, or the Doctrine of the heavenly Bodies; and first of Heliography, or the Philofophy of the Sun. W HAT is the meaning of the B. It is of Greek original, and is compofed of Over: G, Heaven, and Aoy, a Difcourfe; therefore it fignifies a Difcourfe or Treatife of the Heavens, or heavenly Regions, and Bodies therein. A. Pray what do you call the Heavens, or heavenly Regions? B. Thofe Regions, or Fields of Ether, which lie all around us above the Atmofphere; in which are fituated all the fhining Bodies, the Sun, Planets, Comets, and Stars, and wherein they perform all their Motions. A. Where will it be proper for us to commence our Converfations on these celeftial Subjects? B. We will firft begin with Helicgraphy, if you please. A I |