NEW THEORY OF THE ETIOLOGY OF SHOE-BOIL. 
617 
have been taught and told that it is caused by first the shoe and 
then the hoof, or by the foot, and if not by the hoof, then by the 
shoe. Opinion seems to be equally divided as to which causes 
it. Either one or both of these agents cause shoe-boil, or they 
do not, and if they cause shoe-boil, how is the injury produced, 
and if they do not cause shoe-boil, then what does produce it ? 
The question : how and why shoe-boils arise, has been per¬ 
plexing my mind, and as a result I think I have come to a suc¬ 
cessful conclusion as to their origin. For this reason I offer it 
to the members of this society for their consideration. 
Ulnar hygroma , as it is scientifically termed, has been 
ascribed, aside from my own opinion and observations, to be 
directly due to pressure, the result of the shoe being improperly 
applied to the foot, or to the foot itself. Our latest authorities 
claim that the shoe alone causes it, giving various reasons why 
it is thus produced, and describe the manner of its production. 
The animal is either improperly shod, the heels of the shoe are 
too long, or they are purposely made long in order to correct 
some abnormal condition of the foot or gait. The animal while 
in the recumbent position rests the elbow upon the heels of the 
shoe, thus injuring the skin and sensitive structures beneath, 
resulting in the characteristic tumor. First and foremost, if 
such be the case, I cannot understand how a result can exist 
produced by a cause which has no existence. 
I have seen colts which never had a shoe upon their feet 
with shoe-boils, and I have seen horses without shoes have shoe- 
boils come on over night. I have seen horses without shoes 
turned in a loose box stall, and horses without shoes turned out 
in a pasture lot have shoe-boils develop ; and yet they wore no 
shoes. Others have observed the same occurrence, and it 
seemed to make no difference. Shoe or no shoe, they had shoe- 
boils. I have seen horses wearing the rubber pad have shoe- 
boils, and in two instances the pad was advocated as a prevent¬ 
ive measure, and still there were recurrences in both cases. I 
have seen horses shod with the half shoe or tip develop shoe- 
boil, and also cases of acute laminitis and injured feet develop 
