Peripateticall institutions. In the way of that eminent person and excellent philosopher Sr. Kenelm Digby. The theoricall part. Also a theologicall appendix of the beginning of the world. / By Thomas White Gent.

LESSON IV.

Of the essentiall unity and distin∣ction of the Elements and mixt bodies.

1.* 1.1 SInce 'tis said above, that ther's but one possible Substantiall Matter, and Quantity is known to be infinite in power;

the power of Matter, too, to Quantity must needs be infinite: Since, therefore, actu∣ally, Quantity is but finite; the Composit or compound must needs be, in some mea∣sure, dense.

2. And, if whole Nature were uniform, it must be establisht in a certain degree of Density and Rarity, springing from the proportion of Matter to this Quantity: but, the speciall and particular bodies which are in the Universe, as it is now fra∣med, participate, out of this universall proportion, some more some lesse of Den∣sity and Rarity.

3. Since, therefore, the notions of Density and Rarity are the first differences of Magnitudes: those bodies, which first and least of all exceed the nature of Body in common, will be distinguish't by these differences, that some exist in denser parts, others in rarer; which, in our Phy∣sicks, we have said, are the Elements.

4. Since, therefore, the operations of rare and dense bodies, as such, are to di∣vide and be divided; and this last is passi∣on, out of which the essentiall notion is not deduc'd; it comes to passe, that all the Elements receive their differences, ac∣cording to their power of dividing: and

since, to divide is a kind of simple action; they are distinguish't by no other diffe∣rences then of more and lesse, that is, of velocity and slownesse.

5. Among the Elements, therefore, those which are fram'd by nature to divide more swiftly must be more perfect; and those are they which are more subtile: wherefore, since the greatest force of di∣viding agrees to Fire, that must be the no∣blest; next to which must be Aire, then Wa∣ter, then Earth.

6. Which last, though, by its Bulk and density, it may seem more apt to divide, and has, as it were, in the first place, the nature of divisive: yet, by reason of the grossenesse of its parts, in naturall action, it can doe the very least of them all; and consequently, 'tis the vilest and most beg∣garly Instrument.

7. It appears farther that, since a body is, essentially, an Instrument for a determi∣nate motion; and there must needs be some least degree of rarity and density; and the littlenesse in bulk hinders both the divisive power and divisibility: there may be suppos'd, in every Element, parts so little, that, according to the order of the Universe, they may neither have a ca∣pacity

of dividing others, nor of being divided by others; and so, there may not be in them the essentiall notion of an Element, nor of any other naturall body.

8. Again, since all bodies are Conjoin'd;* 1.2 it appears, that such minutest particles never exist, but in composition with others: nay, when ever two or more Elements are joyn'd, it must needs be that their ex∣tremes may be suppos'd in so little a quan∣tity, that one cannot operate without the other.

9. There must needs, therefore, in nature, out of the pure conjunction of the Elements, be a notion of a certain body, whose parts cannot act at all separately, but, in conjunction they may: that is, some body essentially distinct from the E∣lements, and yet, made out of their con∣junction; that is, a body whose essence is to be a Mixtum or mixt body.

10. But, since, in bodies, universally, Unity and Magnitude are consider'd: 'tis plain, the differences of those bodies are collected out of three respects; the speci∣ficall difference of the Elements, that is, the degrees of Density and Rarity; the

Multitude of parts of the same notion; and their Bulk.

11. A Mixtum, therefore, is a body of certain parts, of divers degrees of rarity and density, in a certain number and bulk compacted among themselves, ordain'd by nature for a de∣terminate Motion. Moreover, 'tis evident, that the qualities of the Elements exist re∣fracted and mutually abated in mixt bo∣dies; since, the very least must needs sim∣ply differ in degrees of rare and dense, and these degrees, by reason of the compositi∣on, must needs hinder one another.

12. And yet, that no substantiall Form of any Element is found in a Mixtum: since, a Form constitutes a Thing, and a Thing is ordain'd for Motion; but, Mo∣tion is of the whole, not of the severall parts.

13. Out of what has been said, 'tis evi∣dent, that the operation of a Mixtum is a certain Division qualifi'd by the nature of the parts of the Mixtum: which nature, the better 'tis, that is, the more serviceable for the best works of nature, so much the nobler is the Mixtum, essentially.

14. Again, if the whole mixture of the Elements be shut up into so little a part, that one part cannot, separated from ano∣ther,

have its proper effect; then the Mix∣tum is simply one and primely mixt: but, if the mixture be extended so amply, that many parts may act, asunder, according to the divers parts of the temperament; then, 'tis not a Mixtum, but a Demixtum or Decompositum, that is, one made up of ma∣ny Mixtum's; as we see in Metalls and o∣ther Mines, as Coal, &c. where many Mix∣tum's are joyn'd together, which are apt to be separated by fire or other arti∣fice.

Notes

• * 1.1

  Les. 3. n. 4.
• * 1.2

  B. 2. les. 2. n. 7.