of one of these two, viz. Heaviness or Lightness; he proceeded to consider the Nature of these two Properties, and to examin whether they did belong to Body quatenus Body, or else to some other Quality superadded to Body.  Now it seem’d plain to him, that Gravity and Levity, did not belong to Body as such; for if so, then no Body could subsist without them both:  whereas on the contrary, we find Heavy Bodies which are void of all Lightness, and also some Light Bodies which are void of all Heaviness, and yet without doubt they both are Bodies; in each of which there is something superadded to Corporeity, by which they are distinguish’d one from the other, and that makes the difference between them, otherwise they would be both one and the same thing, in every respect.  From whence it appear’d plainly, that the Essence both of an Heavy, and Light Body was compos’d of two things; One, which was common to them both, viz.  Corporeity, the other, by which they are distinguish’d one from the other, viz.  Gravity in the one, and Levity in the other, which were superadded to the Essence of Corporeity.

Sec. 42.  In like manner he consider’d either Bodies, both Animate and Inanimate, and found their Essence confined in Corporeity and in some, one thing, or more superadded to it.  And thus he attain’d a Notion of the Forms of Bodies, according to their differences.  These were the first things he found out, belonging to the Spiritual World; for these Forms are not the objects of Sense, but are apprehended by Intellectual Speculation.  Now among other things of this kind which he discover’d, it appear’d to him that the Animal Spirit, which is Seal’d in the Heart (as we have mention’d before) must necessarily have some Quality superadded to its Corporeity, which rendred it capable of those wonderful Actions, different Sensations and Ways of apprehending Things, and various sorts of Motions; and that this Quality must be its Form, by which it is distinguish’d from other Bodies (which is the same that the Philosophers call the Sensitive Soul) and so in Plants, that which was in them the same that radical Moisture was in Beasts, was something proper to them, which, was their Form, which the Philosophers call the Vegetative Soul.  And that there was also in inanimate things, (viz. all Bodies, besides Plants and Animals, which are in this sublunary World) something peculiar to them, by the Power of which, every one of them perform’d such Actions as were proper to it; namely, various sorts of Motion, and different kinds of sensible Qualities, and that thing was the Form of every one of them, and this is the same which the Philosophers call Nature.