Astronomical Dialogues.
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the fixed Stars do; besides they are always and all of them in or near this Line here called the Ecliptic: Which you may easily learn to trace out in the Heavens, by these Constellations which compose the Twelve Signs; and if you should, at last, doubt about the Planets, if you see them change as they will do, in some Time, their Distance from any fix'd Star that you know; you may easily distinguish them to be Erraticks or Planets.
I Think, said she, you reckon'd seven Planets just now; sure I have read some where, that there are more.
In that Account above, said I, Madam, I followed only the Vulgar Way of Computation, for in Reality the Sun is no Planet or Wanderer, but a fixed Number of Planets.Star placed in the Center of our System, and in all Probability like the rest of those that we see in the Heavens. And round him, as a Center, Mercury, Venus, Mars, the Earth, Jupiter and Saturn, do revolve, and are now called Primary Planets; because they revolve round the Sun, as their Center: While the others we call Secondary Ones or Satellites, i.e. Guards or Attendants, because they revolve round some one of the Primary Pla-nets,
