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CHAPTER VII. 
Plate VI. — trochlear muscle of the eye, and kidney. 
Fig. 1. The trochlear or superior oblique muscle, arises with the 
straight muscles from the bottom of the orbit. Its muscular portion, 
a , is extended over the upper part of the eye-ball, and gradually as¬ 
sumes the form of a smooth, round tendon, 6, which passes through 
the pulley, c, and is fixed to the inner edge of the orbit, d, then re¬ 
turning backwards and downwards, e is inserted into, the sclerotic 
membrane. The use of this muscle is to bring the eye forwards, 
and to turn the pupil downwards and upwards. 
Fig. 2. A section of the human kidney ; a, the emidgent artery , 
which conveys the blood to, h, the papilla, where the peculiar fluid 
is secreted; from whence it passes by tubes into, c, the pelvis; c, the 
ureter , or tube, which conducts the secretion to its receptacle; 
the emidgent vein , for returning the blood, after it has been submit¬ 
ted to the action of the gland. 
'f '‘""M •* - —* *•' t* /- :• 1 .aufcuwr* ibid* 1* 
