in my two precedent treatises having in due order taken a compendious view and given an account of the celestial bodies, and of the moon which stands between them and the terrestrial, i must now convert my pen to discourse in this third book of meteors, which are beings above the earth and below the moon, and are extended to the site and situation of the earth, which is supposed to be the centre of the sphere of this world; and from thence will i take my beginning.