Acknowledgements, Introduction, John Wilkins, A Discourse Concerning a New World and Another Planet (1640), Thomas Burnet, A Sacred Theory of the Earth (1691), Christiaan Huygens, The Celestial Worlds Discovered (1698), William Whiston, A New Theory of the Earth, from its Original, to the Consummation of All Things (1696) and Astronomical Principles of Religion, Natural and Reveal'd (1717), John Harris, Astronomical Dialogues between a Gentleman and a Lady (1719), Andrew Baxter, Matho: or The Cosmotheoria Puerilis, a Dialogue (1740), Thomas Wright, An Original Theory or New Hypothesis of the Universe (1750), John Hill, Urania: or, A Compleat View of the Heavens (1754), James Ferguson, Astronomy Explained upon Sir Isaac Newton's Principles and Made Easy to Those Who Have Not Studied Mathematics (1756), Roger Long, Astronomy (1764 [actually after 1784]), John Newbery, The Newtonian System of Philosophy (1761), William Herschel, 'Catalogue of a Second Thousand of New Nebulae and Clusters of Stars', Philosophical Transactions (1789) and 'On the Nature and Construction of the Sun', Philosophical Transactions (1795), Robert Harrington, A New System on Fire and Planetary Life (1796) , Adam Walker, An Epitome of Astronomy (1817), John Herschel, Preliminary Discourse on the Study of Natural Philosophy (1830), Bibliography, Notes
