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To the head of the bone’s lying in this fpace, it was 
probably owing that we were at firft deceived; fince its 
being there allowed a greater latitude of motion, than 
could poflibly have been the cafe any where elfe ; 
which may ferve to account tor the parallelifm of 
the limb to that of the other, notwithftanding a 
luxation. 
But, on turning the foot inward and outward by 
turns, while an afliftant laid his hand on the head of 
the bone, a grating was perceived, both by the pa- 
tient and us all. I his fomewhat furprized us at firft ; 
but, as this grating was never to be perceived, with- 
out prefling pretty hardly on the head of the bone, 
at the time the limb was turned round, and as the 
head of the bone was plainly felt to turn round, 
whenever the thigh had that motion given to it, we 
concluded it could be nothing but the fide of the 
head of the femur againft the edge of the ifehium. 
Convinced of this, we determined to make an ex- 
tenfion ; and, to that end, brought him to the foot 
of the bed, and placed him on his back, with the 
bed’s poll between his thighs, which was wrapped 
round with cloths, to prevent its galling him. . A 
napkin was tied round his leg, at the ancle, which 
two afliftants pulled on, while a third turned the 
knee outward, and I had my hand on the head of 
the bone, prefling it downward. As foon as the 
extenfion began, I perceived plainly the bone link 
under my hand, which I had hardly time to fay, 
before it gave a fnap, which was felt by the patient, 
and heard by us all, and the bone was reduced. 
When he was laid on his back in the bed, the 
right leg appeared fomewhat longer than the othei ; 
