the Planetary Worlds.
33
Book I.
which can ſwim in Water as well as walk on Land, or fly in the Air; or like our Crocodiles and Sea-Horſes, muſt be Mongrels, between Land and water. There can no other Method be imagined but one of the theſe. For where is it poſſible for Animals to live, except upon ſuch a ſolid Body as our Earth, or a fluid one like the Water, or ſtill a more fluid one than that, ſuch as our Air is? The Air I confeſs may be much thicker and heavier than ours, and ſo, without any Diſadvantage to its Tranſparency, be fitter for the volatile Animals. There may alſo be many ſorts of Fluids ranged over one another in Rows as it were. The Sea perhaps may have ſuch a fluid lying on it, which tho’ ten times lighter than Water, may be a hundred Times heavier than Air; whoſe utmoſt Extent may not be ſo large as to cover the higher Places of their Earth. But there’s no Reaſon to ſuſpect or allow them this, ſince we have no ſuch Thing; and if we did, it would be of no Advantage to them, for that the former Ways of moving would not be hereby at all in-
which can ſwim in Water as well as walk on Land, or fly in the Air; or like our Crocodiles and Sea-Horſes, muſt be Mongrels, between Land and water. There can no other Method be imagined but one of the theſe. For where is it poſſible for Animals to live, except upon ſuch a ſolid Body as our Earth, or a fluid one like the Water, or ſtill a more fluid one than that, ſuch as our Air is? The Air I confeſs may be much thicker and heavier than ours, and ſo, without any Diſadvantage to its Tranſparency, be fitter for the volatile Animals. There may alſo be many ſorts of Fluids ranged over one another in Rows as it were. The Sea perhaps may have ſuch a fluid lying on it, which tho’ ten times lighter than Water, may be a hundred Times heavier than Air; whoſe utmoſt Extent may not be ſo large as to cover the higher Places of their Earth. But there’s no Reaſon to ſuſpect or allow them this, ſince we have no ſuch Thing; and if we did, it would be of no Advantage to them, for that the former Ways of moving would not be hereby at all in-
C 4
creas’d
