the luminous body to be of a deep _Blue_; and these colours will appear
deeper and deeper, according as the Rays from the luminous body fall more
_obliquely_ on the surface of the Water, and thereby suffer a greater
refraction, and the more distinct, the further cdef is removed from the
trajecting hole.

So that upon the whole, we shall find that the reason of the _Phænomena_
seems to depend upon the _obliquity_ of the _orbicular pulse_, to the Lines
of Radiation, and in particular, that the Ray cd which constitutes the
_Scarlet_ has its inner parts, namely those which are next to the middle of
the luminous body, precedent to the outermost which are contiguous to the
dark and _unradiating_ skie. And that the Ray ef which gives a _Blue_, has
its outward part, namely, that which is contiguous to the dark side
precedent to the pulse from the innermost, which borders on the bright
_area_ of the luminous body.

We may observe further, that the cause of the _diluting_ of the colours
towards the middle, proceeds partly from the wideness of the hole through
which the Rays pass, whereby the Rays from several parts of the luminous
body, fall upon many of the same parts between c and f as is more manifest
by the Figure: And partly also from the nature of the refraction it self,
for the vividness or strength of the two terminating colours, arising
chiefly as we have seen, from the very great difference that is betwixt the
outsides of those _oblique undulations_ & the dark Rays circumambient, and
that disparity betwixt the _approximate_ Rays, decaying gradually: the
further inward toward the middle of the luminous body they are remov'd, the
more must the colour approach to a white or an undisturbed light.

Upon the calculation of the refraction and reflection from a Ball of Water
or Glass, we have much the same _Phænomena_, namely, an _obliquity_ of the