a third _medium_) toward its perpendicular: As I
call Glass a more dense body then Water, and Water a more rare body then
Glass, because of the refractions (more or less deflecting towards the
perpendicular) that are made in them, of a Ray of light out of the Air that
has the same inclination upon either of their superficies.

So as to the business of Refraction, spirit of Wine is a more _dense_ body
then Water, it having been found by an accurate Instrument that measures
the angles of Refractions to Minutes that for the same refracted angle of
30 deg..00'. in both those _Mediums_, the angle of incidence in Water was
but 41 deg..35'. but the angle of the incidence in the trial with spirit of
Wine was 42 deg.45'. But as to gravity, Water is a more _dense_ body then
spirit of Wine, for the proportion of the same Water, to the same very well
rectify'd spirit of Wine was, as 21. to 19.

So as to Refraction, Water is more Dense then Ice; for I have found by a
most certain Experiment, which I exhibited before divers illustrious
Persons of the _Royal Society_, that the Refraction of Water was greater
then that of Ice, though some considerable Authors have affirm'd the
contrary, and though the Ice be a very hard, and the Water a very fluid
body.

That the former of the two preceding Propositions is true, may be
manifested by several Experiments; As first, if you take any two liquors
differing from one another in density, but yet such as will readily mix: as
Salt Water, or Brine, & Fresh; almost any kind of Salt dissolv'd in Water,
and filtrated, so that it be cleer, spirit of Wine and Water; nay, spirit
of Wine, and spirit of Wine, one more highly rectify'd then the other, and
very many other liquors; if (I say) you take any two of these liquors, and
mixing them in a Glass Viol, against one side of which you have fix'd or
glued a small round piece of Paper, and shaking them well together (so that
the parts of them may be somewhat disturb'd and move up and down) you
endeavour to see that round piece of Paper through the body of the liquors,
you shall plainly perceive the Figure to wave, and to be indented much
after the same manner as the limb of the Sun through a _Telescope_ seems to
be, save onely that the mutations here, are much quicker. And if, in steed
of this bigger Circle, you take a very small spot, and fasten and view it
as the former, you will find it to appear much like the twinkling of the
Starrs, though much quic