Organs of Sense. For that Motion which can continue long in one and the
same part of a Body, can be propagated a long way from one part to
another, supposing the Body homogeneal, so that the Motion may not be
reflected, refracted, interrupted or disorder'd by any unevenness of the
Body.
_Qu._ 13. Do not several sorts of Rays make Vibrations of several
bignesses, which according to their bignesses excite Sensations of
several Colours, much after the manner that the Vibrations of the Air,
according to their several bignesses excite Sensations of several
Sounds? And particularly do not the most refrangible Rays excite the
shortest Vibrations for making a Sensation of deep violet, the least
refrangible the largest for making a Sensation of deep red, and the
several intermediate sorts of Rays, Vibrations of several intermediate
bignesses to make Sensations of the several intermediate Colours?
_Qu._ 14. May not the harmony and discord of Colours arise from the
proportions of the Vibrations propagated through the Fibres of the
optick Nerves into the Brain, as the harmony and discord of Sounds arise
from the proportions of the Vibrations of the Air? For some Colours, if
they be view'd together, are agreeable to one another, as those of Gold
and Indigo, and others disagree.
_Qu._ 15. Are not the Species of Objects seen with both Eyes united
where the optick Nerves meet before they come into the Brain, the Fibres
on the right side of both Nerves uniting there, and after union going
thence into the Brain in the Nerve which is on the right side of the
Head, and the Fibres on the left side of both Nerves uniting in the same
place, and after union going into the Brain in the Nerve which is on the
left side of the Head, and these two Nerves meeting in the Brain in such
a manner that their Fibres make but one entire Species or Picture, half
of which on the right side of the Sensorium comes from the right side of
both Eyes through the right side of both optick Nerves to the place
where the Nerves meet, and from thence on the right side of the Head
into the Brain, and the other half on the left side of the Sensorium
comes in like manner from the left side of both Eyes. For the optick
Nerves of such Animals as look the same way with both Eyes (as of Men,
Dogs, Sheep, Oxen, &c.) meet before they come into the Brain, but the
optick Nerves of such Animals as do not look the same way with both Eyes
(as of Fishes, and of the Chameleon,) do not meet, if I am rightly
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