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Mr. Bell on the motions of the eye, &c. 
upper eye-lid ! The motion of elevation in the lower eye-lid 
was of course performed by an encreased action of the lower 
portion of the orbicularis palpebrarum. 
The Author has to regret that these minute circumstances 
regarding the action of the muscles of the eye have led him 
to so great a length ; he hopes they are not altogether with- 
out interest in themselves, while the discussion will afford him 
secure ground for establishing an arrangement of the nerves 
of the eye, and will enable him to distinguish them according 
to their uses. 
EXPLANATION OF PLATE XXI. 
Fig. 1 . The muscles of the eye seen in front. 
A. B. C. D. The recti muscles ; voluntary muscles. 
E. The superior oblique muscle or trochlearis. 
a. The trochlea cut off from the bone and left attached to 
the tendon. It is a loop through which the tendon runs. 
b. The tendon of the trochlearis muscle expanding and 
running to its insertion. 
G. The inferior oblique muscle. It is seen, like the tendon 
of the superior oblique, to run backwards and outwards. 
Fig. 2. The muscles of the eye seen in profile. 
A. B. . D. Three of the recti muscles. They arise to- 
gether from the periosteum of the bottom of the orbit, and are 
inserted into the anterior part of the sclerotic coat of the eye. 
E. The superior oblique muscle, or trochlearis. 
a. The trochlea. 
b. The reflected tendon inserted into the back and outer 
part of the sclerotic coat. 
G. The inferior oblique muscle. 
c. Its origin from the anterior part of the orbit. 
d. Its insertion into the back and outer part of the eye-ball. 
