was held in the white beam of the Sun's Light, and cast a Shadow which
was border'd with three Fringes of coloured Light, those Colours arose
not from any new modifications impress'd upon the Rays of Light by the
Hair, but only from the various inflexions whereby the several Sorts of
Rays were separated from one another, which before separation, by the
mixture of all their Colours, composed the white beam of the Sun's
Light, but whenever separated compose Lights of the several Colours
which they are originally disposed to exhibit. In this 11th Observation,
where the Colours are separated before the Light passes by the Hair, the
least refrangible Rays, which when separated from the rest make red,
were inflected at a greater distance from the Hair, so as to make three
red Fringes at a greater distance from the middle of the Shadow of the
Hair; and the most refrangible Rays which when separated make violet,
were inflected at a less distance from the Hair, so as to make three
violet Fringes at a less distance from the middle of the Shadow of the
Hair. And other Rays of intermediate degrees of Refrangibility were
inflected at intermediate distances from the Hair, so as to make Fringes
of intermediate Colours at intermediate distances from the middle of the
Shadow of the Hair. And in the second Observation, where all the Colours
are mix'd in the white Light which passes by the Hair, these Colours are
separated by the various inflexions of the Rays, and the Fringes which
they make appear all together, and the innermost Fringes being
contiguous make one broad Fringe composed of all the Colours in due
order, the violet lying on the inside of the Fringe next the Shadow, the
red on the outside farthest from the Shadow, and the blue, green, and
yellow, in the middle. And, in like manner, the middlemost Fringes of
all the Colours lying in order, and being contiguous, make another broad
Fringe composed of all the Colours; and the outmost Fringes of all the
Colours lying in order, and being contiguous, make a third broad Fringe
composed of all the Colours. These are the three Fringes of colour'd
Light with which the Shadows of all Bodies are border'd in the second
Observation.
When I made the foregoing Observations, I design'd to repeat most of
them with more care and exactness, and to make some new ones for
determining the manner how the Rays of Light are bent in their passage
by Bodies, for making the Fringes of Colours with the dark lines between
them. But I was then interrupted, and cannot now think of taking these
things into farther Consideration. And since I have not finish'd this
part of my Design, I shall conclude with proposing only some Queries, in
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