And
because this _medium_ is more easily _trajected_ then the former by a
third, therefore the point C of the orbicular pulse FC will be mov'd to H
four spaces in the same time that F the other end of it is mov'd to G three
spaces, therefore the whole refracted pulse GH shall be _oblique_ to the
refracted Rays CHK and GI; and the angle GHC shall be an acute, and so much
the more acute by how much the greater the refraction be, then which
nothing is more evident, for the sign of the inclination is to the sign of
refraction as GF to TC the distance between the point C and the
perpendicular from G on CK, which being as four to three, HC being longer
then GF is longer also then TC, therefore the angle GHC is less than GTC.
So that henceforth the parts of the pulses GH and IK are mov'd ascew, or
cut the Rays at _oblique_ angles.
It is not my business in this place to set down the reasons why this or
that body should impede the Rays more, others less: as why Water should
transmit the Rays more easily, though more weakly than air. Onely thus much
in general I shall hint, that I suppose the _medium_ MMM to have less of
the transparent undulating subtile matter, and that matter to be less
implicated by it, whereas LLL I suppose to contain a greater quantity of
the fluid undulating substance, and this to be more implicated with the
particles of that _medium_.
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