500 
COMMUNICATION FROM MR. DADD. 
the bones replaced with a snap ; but the condition of the parts 
was so unfavorable, that on moving the limb the dislocation 
recurred. Reduction was again and again effected, with the 
same result. I concluded there was some fracture of the 
acetabulum or of the head of the femur ; but could obtain 
no positive evidence. The cow was then left in much the 
same condition as we found her, only somewhat exhausted 
from the pain and excitement attendant on the operation. 
I have seen her this morning (July 3d), and found her 
in good bodily health, and the dislocation appeared to have 
been reduced. On inquiry I ascertained that, to relieve the 
sore surfaces on the left side, Mr. Cairns had the cow turned 
over on to the right. Struggling in this painful position as 
she lay on her injured limb, a partial restoration of the parts 
had occurred. On moving the limb, though with great care, 
the femur fell back into its old place, and I for the first time 
recognised a fracture of its head or neck, having obtained 
clear evidence of bony grating. 
If I bring this case under your special notice now, it is to 
show that the uncertainty of cure depends upon the com- 
plications, and not on the difficulty or supposed impossibility 
of reduction. You will perceive, gentlemen, that extension 
and counter-extension could be of no avail without the rope 
and pulley. The men pulled the head of the femur down- 
wards out of the obturator foramen, and I had perfect 
command over the parts, in virtue of the lever formed by the 
femur acting on the suspended rope as on a fixed fulcrum. 
Under other circumstances you may find yourselves without 
pulleys and beams ; a barrel or wooden block will then serve to 
place under the affected thigh, and the conditions required for 
reduction as efficiently ensured. 
Such a case as the one just related is instructive in showing 
that, if the principle on which to proceed be understood, a 
little ingenuity may overcome great difficulties. Readiness 
in the adaptation of means to ends may be an inborn talent, 
but is unquestionably acquired by education and practice. 
(To be continued .) 
COMMUNICATION FROM G. H. DADD, M.D. 
Boston, Mass., U.S.; July 18, 1856. 
Gentlemen, — In the July number of your time-honoured 
periodical, the Veterinarian , I notice an urticle having refer- 
