otherwise be of any other Figure then _Globular_: For being by the
_heterogeneous_ fluid equally _protruded_ every way, whatsoever part is
_protuberant_, will be thereby _deprest_. From this cause it is, that in
its effects it does very much resemble a _round Spring_ (such as a _Hoop_.)
For as in a _round Spring_ there is required an additional _pressure_
against two opposite sides, to reduce it into an _Oval_ Form, or to force
it in between the sides of a _Hole,_ whose _Diameter_ is less then that of
the _Spring_, there must be a considerable force or _protusion_ against
_the concave_ or inner side of the _Spring_; So to alter this _spherical_
constitution of an included fluid body, there is required more pressure
against opposite sides to reduce it into an _Oval_; and, to press it into
an _Hole_ less in _Diameter_ then it self, it requires a greater
_protrusion_ against all the other sides, What degrees of force are
requisite to reduce them into longer and longer _Ovals_, or to press them
into less and less _holes_, I have not yet experimentally calculated; but
thus much by experiment I find in general, that there is alwayes required a
greater pressure to close them into longer _Ovals_, or protude them into
smaller _holes_. The necessity and reason of this, were it requisite, I
could easily explain: but being not so necessary, and requiring more room
and time then I have for it at present, I shall here omit it; and proceed
to shew, that this may be presently found true, if Experiment be made with
a _round Spring_ (the way of making which trials is _obvious_ enough.) And
with the fluid bodies of _Mercury_, _Air_, _&c_, the way of trying which,
will be somewhat more difficult; and therefore I shall in brief describe
it. He therefore that would try with _Air_, must first be provided of a
_Glass-pipe_, made of the shape of that in the _fifth Figure_, whereof the
side AB, represents a straight _Tube_ of about three foot long, C,
represents another part of it, which consists of a _round Bubble_; so
ordered, that there is left a _passage_ or _hole_ at the top, into which
may be fastened with _cement_ several _small Pipes_ of determinate