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nerves of the orbit of the eye. 
nation of the motions of the eyeball and eyelids as I have 
before noticed ; and secondly, that the nerves which move 
the eyelids, and the nerve of the obliquus muscle of the eye- 
ball, are associated at their roots ; but I should not do full 
justice to this interesting subject, if I did not attempt some- 
thing farther. 
It is plain that we must consider the nerves and muscles 
of the eyelids in a double capacity, in their voluntary, and 
involuntary actions. In the first, the motions of the eyelids 
combine with the whole muscles of the eyeball, as we may 
perceive in the voluntary contractions and squeezing of the 
eye ; but in the insensible and involuntary motions of the 
eyelids, there would be no sympathy with the muscles of the 
eyeball, and therefore no correspondence in the motion of 
these parts, without a nerve of the nature of the fourth ; 
that is, a nerve which having diverged from the root of the 
respiratory nerves, takes its course to the oblique muscles. 
In one word, the connection of its root declares the office of 
this nerve. 
The expression of the eye in passion, confirms the truth of 
this relation being established by a respiratory nerve, and con- 
sequently by a nerve of expression. In bodily pain, in agony 
of mind, and in all this class of passions, the eyes are raised 
and dragged, in conjunction with the changes to which the 
other features are subjected. If it be asked now, as it has 
been asked for some hundred years past, why the fourth 
nerve goes into the orbit, where there are so many nerves, 
why it is so distant in its origin from the other nerves, and 
why it sends off no twig or branch, but goes entirely to one 
muscle of the eye ? The answer is, to provide for the insen- 
mdcccxxiii. Q q 
