_Materia Subtilis_, as the
_Cartesians_ imploy to explicate most of the _Phaenomena_ of Nature.

The _Treatise_ consisting of a _Speculative_, and an _Historical_ part, the
Author, with great modesty leaves the _Reader_ to judge; _Whether_ in the
_First_ part he hath treated of the _Nature_ and _Origine of Forms and
Qualities_ in a more Comprehensive way, than others; _Whether_ he has by
fit Examples, and other means, rendred it more intelligible, than they have
done: _Whether_ he has added any considerable number of Notions and
Arguments towards the compleating and confirming of the proposed
_Hypothesis_: _Whether_ he has with reason dismissed Arguments unfit to be
relied on; and _Whether_ he has proposed some Notions and Arguments so
warily, as to keep them from being liable to Exceptions and Evasions,
whereto they were obnoxious, as others have proposed them. And, as to the
_Second_ and _Historical_ part, he is enclin'd to believe that the _Reader_
will grant, he hath done that part of _Physicks_, he is treating of, some
service, by strengthning the doctrines of the _New Philosophy_ (as 'tis
call'd) by such particular Experiments, whose Nature and Novelty will
render them as well Acceptable as Instructive.

The _summe_ of the _Hypothesis_, fully and clearly explicated in the
_First_ Part, is this;

That all Bodies are made of _one Catholick matter_, common to them all, and
differ but in _Shape, Size, Motion_ or _Rest_, and _Texture_ of the small
parts, they consist off; from which {193} Affections of Matter, the
_Qualites_, that difference particular Bodies, result: whence it may be
rationally concluded, that one kind of Bodies may be transmuted into
another; _that_ being in effect no more, than that one Parcel of the
Universal Matter, wherein all Bodies agree, may have a _Texture_ produced
in it, like the _Texture_ of some other Parcel of Matter, common to them
both.

To this _Hypothesis_, is subjoin'd an Examination of the _Scholastick_
opinion of _Substantial Forms_; where the Author, _first_, States the
Controversie; _next_, gives the Principal reasons, that move him to oppose
that Opinion; _then_, answers the Main arguments employed to evince it;
_further_, assigns both the _First_ Cause of Forms (_God_;) and the Grand
_Second_ Cause thereof (_Local Motion_:) and _lastly_, proves the
_Mechanical_ Production of _Forms_; grounding his proof, _partly_ upon the
Manner, by which such a _Convention of Accidents_, a